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HomeMy WebLinkAboutSWP272117(7) � SRm167 I5TH STREET S.W. TO � SOUTH GRADY WAY Hydraulic Report Volume I� Data and Calculations ■ 1 0 HOV Improvements 0 Ramp Metering OSurveillance, Control, and Driver Information 1 AO` Washington State cts TrAf Department of Transportation ' HYDRAULIC REPORT ' SR 167 MP 13 . 73 to MP 26 . 37 i15th Street S . W. to South Grady Way XL - 0647 PIN - 116703B tWASHINGTON STATE DEPARTMENT OF TRANSPORTATION District No. 1 ' Seattle, Washington ALPHA ENGINEERING GROUP, INC. 16040 Christensen Road Seattle, Washington 98188-2929 CTS ENGINEERS, INC. 2115 112TH Ave. N.E. B - "evue, Washington 98004 1 YROC�� ti.0 wasI ..t, Ci i. S py ✓ cu��^es T. C. HAMSTRA, P.E. Project Engineer ' R. A. ANDERSON, P. E. R. D. AYE, P.E. District Administrator District Project Development Engineer C. L. KURTZWEG, P. E. ' Assistant Project Development Engineer (North) ' HYDRAULIC REPORT SR 167 MP 13 . 73 to MP 26 . 37 ' 15th Street S .W. to South Grady Way ' TABLE OF CONTENTS CHAPTER ITEM PAGE 1 . 0 Vicinity Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 . 0 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 ' 3 . 0 Existing Drainage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3 . 1 Section 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 ' Existing Flood Plains . . . . . . . . . . . . . . . . . . . . . . . . . 5 Existing Stream Crossings . . . . . . . . . . . . . . . . . . . . . 6 ' Existing Culverts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 ' Existing Ditches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Existing Subsurface Drainage. . . . . . . . . . . . . . . . . . 9 Existing Bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 3 . 2 Section 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Existing Flood Plains . . 10 ' Existing Stream Crossings . . . . . . . . . . . . . . . . . . . . 10 ' Existing Culverts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Existing Ditches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Existing Subsurface Drainage. . . . . . . . . . . . . . . . . 12 Existing Bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3 . 3 Section 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 TABLE OF CONTENTS (Continued) CHAPTER ITEM PAGE Existing Flood Plains . . . . . . . . . . . . . . . . . . . . 14 ' ExistingStream Crossings . . . . . . . . . . . . . . . . 15 9 Existing Culverts . . . . . . . . . . . . . . . . . . . . . . . . 15 Existing Ditches . . . . . . . . . . . . . . . . . . . . . . . . . 18 Existing Subsurface Drainage. . . . . . . . . . . . . 19 1 Existing Bridges . . . . . . . . . . . . . . . . . . . . . . . . . 19 3 . 4 Other Projects . . . . . . . . . . . . . . . . . . . . . . . . . 19 ' 4 . 0 Proposed Improvements . . . . . . . . . . . . . . . . . . . . 21 4 . 1 Design Criteria. . . . . . . . . . . . . . . . . . . . . . . . . . 21 4 . 2 Design References . . . . . . . . . . . . . . . . . . . . . . . . 23 4 . 3 Section 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Alternative A. . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Alternative B. . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Streams . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . 24 Flood Plain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 ' Channel Changes . . . . . . . . . . . . . . . . . . . . . . . . . . 25 ' Culverts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Culvert End Sections . . . . . . . . . . . . . . . . . . . . . 25 ' Ditches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,5 Enclosed Drainage . . . . . . . . . . . . . . . . . . . . . . . . 26 Gutter Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 ' Detention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 TABLE OF CONTENTS (Continued) ' CHAPTER ITEM PAGE Subsurface Drainage. . . . . . . . . . . . . . . . . . . . . . . 28 ' Existing Utilities . . . . . . . . . . . . . . . . . . . . . . . . 28 Water Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Fish and Wildlife Requirements . . . . . . . . . . . . 28 Other Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Pipe Alternates . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 ' 4 . 4 Section 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 ' General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Streams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Flood Plain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Channel Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 ' Culverts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Culvert End Sections. . . . . . . . . . . . . . . . . . . . . . 32 Ditches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Enclosed Drainage . . . . . . . . . . . . . . . . . . . . . . . . . 32 Gutter Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Detention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Subsurface Drainage. . . . . . . . . . . . . . . . . . . . . . . 34 Existing Utilities . . . . . . . . . . . . . . . . . . . . . . . . 34 ' Water Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Fish and Wildlife Requirements . . . . . . . . . . . . 35 Other Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Pipe Alternates . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 1 ' TABLE OF CONTENTS (Continued) ' CHAPTER ITEM PAGE 4 . 5 Section 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Streams . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . 37 Flood Plain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 ' Channel Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Culverts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Culvert End Sections . . . . . . . . . . . . . . . . . . . . . . . 40 Ditches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Enclosed Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Gutter Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Detention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 ' Subsurface Drainage. . . . . . . . . . . . . . . . . . . . . . . . 52 1 Existing Utilities . . . . . . . . . . . . . . . . . . . . . . . . . 52 Water Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Fish and Wildlife Requirements . . . . . . . . . . . . . 52 Other Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 ' Pipe Alternates . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 5 . 0 Drainage Basins . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 ' 6 . 0 Appendix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 ' TABLE OF CONTENTS (Continued) ' CHAPTER ITEM 7 . 0 Drainage Analysis 7 . 1 General ' 7 . 2 Biofiltration, Conveyance & Detention - Section 1 7 . 3 Biofiltration, Conveyance 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The ' widening will be used for installation of HOV lanes in this transportation corridor and for the most part of it is accomplished by widening the northbound and southbound lanes toward the median with exceptions of the interchange ramps which are being widened to the outside . ' For ease of planning, the proposed stretch of freeway to be widened has been divided into three sections : A. Section 1 starts at 15th Street S .W. in Auburn and ends at the Green River Bridge, approximately between Sta. 493+00 and Sta. 772+00 . B. Section 2 continues from the Green River Bridge to the 84th ' Avenue South overcrossing Sta. 892+50 . ' C. Section 3 stretches from the 84th Avenue South bridge to South Grady Way. ' SR 167 is class-ified as a Type P-1 Highway ( 1984 Functional Classification) traversing level terrain. The entire project is located in a mixture of rural and urban areas of King County and runs through the city limits of Auburn, Kent and Renton, thus impacting all three cities and unincorporated land located in King County . 1 2 3 . 0 EXISTING DRAINAGE ' In general terms, SR 167 shares the Green River Valley with other important transportation routes in a north-south direction. Examples are the West Valley Road (SR 181 ) , East Valley Road (known also as 84th Avenue South or Auburn Way North through the project) , Chicago Milwaukee St. Paul & Pacific Railroad and Burlington Northern Railroad. • In addition to these major routes, there are numerous streets increasing in density near the central core of each of the cities and major transportation links in the ' east-west direction, such as, SR 18, SR 516, South 212th Street, S .W. 43rd Street and SR 405 . All of these man-made routes are elevated above the actual grade ' of the valley thus forming obstacles to the natural drainage flow which is already impeded by the flatness of the entire area. The ' natural grade change for the whole length of the project changes from elevation 64 . 00 at the south end to elevation 14 . 00 at the north end. The main collector of the surface water in the valley is the ' Green River which meanders in a south to north direction with SR 167 being generally parallel to it, except for the area where the , freeway crosses the river. In Section 1 of the project, SR 167 follows Mill Creek (Auburn) , a tributary to Green River. Further north in Section 2, SR 167 crosses Mill Creek (Kent) . In Section 3, SR 167 crosses Springbrook Creek and its tributary, Garrison ' Creek. Further north SR 167 forms a "dam" for Panther Creek Wetland along the east side of the freeway within the City of Renton limits . ' The following description of the existing drainage conditions and drainage structures in the individual sections is based on maps provided by Alpha Engineers and field-verified by CTS Engineers, , Inc. technical personnel . 3 . 1 Section 1 General In Section 1 , SR 167 has been constructed with a wide median between the northbound and southbound lanes . For the most part, the roadway superelevation carries the storm water to the outside edges with the exception of two curves in which the water is ' carried to the median from the respective lanes . The median is drained by a series of catch basins located in the middle at intervals often exceeding 900 feet. Each individual catch basin ' is drained by a 12-inch diameter pipe either to the east or west side of the freeway . Closed circular ramps drain to the space they enclose which is in turn being drained to the outside of the intersection by one specific pipe . Open ramps drain to the , 3 ' outside either by sheet flow or in case of having a curb by catch ' basin and pipe system. A 10' x 6' double box culvert located at Sta. 504+60 carries Mill Creek (Auburn) from the east side of the freeway towards the west. A 24-inch dia. culvert at Sta. 534+40 carries storm water from east to west and into adjacent Mill Creek (Auburn) . A 36- inch diameter culvert located at Sta. 541 +00 has been installed per Utility Agreement No. GC-2711 (Supplement No. 2 ) with City of Auburn. The available records show this culvert is sloping from east to west. North of West Main Street another 24-inch culvert drains runoff from east to west side of freeway. The storm water then continues north via open channel to a special ditch located at approximate Sta. 558+00 and heading west to Mill Creek (Auburn) . The special ditch is part of a 50-foot wide drainage ' easement. The next 24-inch culvert located at Sta. 585+40 provides drainage connection for east to west flow and opens directly into another special ditch going west into Mill Creek ' (Auburn) . The drainage south of 15th St . N.W. Undercrossing ends up in the same special ditch. The drainage north of 15th St. --N.W. is directed toward a 8' x 6' box culvert at Sta. 615+50 which serves as another conduit for Mill Creek (Auburn) , ' crossing the freeway from west to east . A 30-inch diameter pipe at Sta. 638+30 carries water from the west to the east side of the freeway and into Mill Creek where 29th Street N.W. abuts the ' freeway . North of the 30-inch pipe, three 24-inch pipes, at different locations, fulfill a similar purpose . A 7' x 8' box culvert carries Mill Creek (Auburn) from the east to the west ' side of the freeway at Sta. 691 +00 . Just before the South 277th Street interchange, a 41 x 4' box culvert carries water from the east to the west side of the freeway and towards Mill Creek (Auburn) (approx. Sta. 707+35 ) . The south 277th St. is a northern boundary of City of Auburn. North of this street the project borders unincorporated King County and City of Kent. Between S . 277th and 24-inch dia. culvert at Sta. 723+00 the storm runoff is directed north and using the above culvert drains from west to east, crosses the frontage road and follows this road north toward Green River in an open channel . The 24-inch dia. pipe at Sta. 723+00 also serves to drain the area between ' its location and a high point of ground located around Sta. 731 +00 to 736+00 . , From the high point the runoff drains north to a 30-inch dia. culvert which drains from west to east and is ' located at Sta. 748+55 . The storm water eventually ends up in the open channel running along the east side of the frontage road. The same 30-inch dia. culvert serves area north of it up to about Sta. 762+00 . At this station the frontage road takes 90 ' degrees turn to east but the open ditch continues north toward the Green River. An 18-inch diameter pipe at Sta. 757+50 serves to carry water ponding between 72nd Avenue South and SR 167 from ' the east to the west side of the freeway . The area between Sta. 762+00 and Green River is drained either to the aforementioned open ditch or directly to Green River. The open ditch is ' connected to a pump station operated by Milwaukee, St. Paul & Pacific Railroad . It is an opinion of City of Kent that this ' 4 pump station which is pumping ,into Green River is obsolete and undersized. Agreement which would turn this station to City of Kent failed. Green River crossing is at Sta. 772+50 . ' Existing Flood Plains In Section 1 the project lies within or is adjacent to a Mill ' Creek (Auburn) flood plain. The following data relate to 100- year flood unless otherwise noted. At the beginning of the project at 15th St. -S .W. the Mill Creek (Auburn) runs along the east side of SR 167 being adjacent to the existing northbound on- ramp with flood elevation of 69 . 0 , according to FIRM (Flood Insurance Rate Map) Panel 461 . The said on-ramp is adjacent to floodway area Zone AE ( flood elevations determined) . At elevation 69 . 0 the flood will encroach anywhere from 70 to 30 feet into the SR 167 right-of-way, but it will not reach the ' traveled part of the on-ramp since the lowest point of the pavement is at elevation 75 . 0 . In the northern part of this flood area the existing SR 167 off-ramp to SR 18 eastbound is as low as elevation 69 . 0 and is affected by the flood. As Mill , Creek (Auburn) crosses SR 167 the flood plain moves to the west side of SR 167 . In this area the flood level varies from elevation 69 . 0 at the crossing to elevation 66 . 0 at SR 18 . ' As Mill Creek crosses SR 18 its gradient during the flood drops from elevation 66 . 0 to elevation 63 . 0 and the flood level remains at elevation 62 . 0 for the creek stretch between SR 18 and West ' Main Street with only the stream bed classified as a floodway. In the area between West Main Street and 15th St . N.W. Mill Creek , (Auburn) remains on the west side of SR 167 and again only the stream bed is classified as a floodway except that flood can back into the two culverts connecting the area east of SR 167 with ' Mill Creek (Auburn) causing the flood area to expand over the entire stretch from West Main Street to 15th St . N.W. along the east side of SR 167 with northern part of this area being designated as a floodway. The flood level gradient drops from elevation 62 . 0 at West Main St . to elevation 56 . 0 at 15th St. N.W. After Mill Creek (Auburn) crosses under 15th St . N.W. it remains , on the west side of SR 167 for about 1600 feet before it crosses under SR 167 to the east side . While the creek is on the west side of SR 167 the freeway is adjacent to the Mill Creek (Auburn) ' flood area. During the crossing of 15th St . N.W. the flood level gradient drops from elevation 56 . 0 to elevation 53 . 0 . The flood level drops further to elevation 51 . 0 before Mill Creek (Auburn) ' crosses SR 167 . After crossing of SR 167 Mill Creek (Auburn) continues eastward making a wide loop before it comes back just north of 29th St . N.W. to run in northerly direction along the ' east side of SR 167 all the way to 37th St . N.W. In this stretch the flood level gradient drops from elevation 51 . 0 to elevation 45 . 0 . Except the stream bed itself none of the flood plain is designated as floodway area. Actually from the point of crossing ' 5 SR 167 to 29th St. N.W. the area adjacent to SR 167 along its east side is not only out of 100-year flood level, but also out of 500-year flood level . The west side of SR 167 in the same stretch borders 500-year flood level . After that even this side ' of SR 167 is out of 500-year flood level .. After crossing under 37th St. N.W. , Mill Creek (Auburn) continues north along east side of SR 167 for about 2700 feet until it crosses under SR 167 to the west again makes a small loop away from the freeway but comes back to run adjacent to the south bound on-ramp from South 277th St. While Mill Creek (Auburn) ' remains on the east side the east stretch of SR 167 from 37th St. N.W. to the culvert is adjacent to flood plain designated as flood area with the gradient dropping from elevation 45 . 0 to elevation 42 . 0 . The remaining east side of the freeway from the culvert to South 277th St . is protected from the flood plain by a frontage road and is out of 500-year flood level . The west side of SR 167 is also out of 500-year flood level from 37th Street N.W. to the Mill Creek (Auburn) culvert . However, once Mill Creek (Auburn) crosses SR 167 from east to west the entire west side of SR 167 from point of crossing to Green River is designated as a floodway area belonging to Green River backwater inundation area with flood level elevation 42 . 0 . The entire east side of SR 167 from South 277th Street to Green River is out of 500-year flood plain. Existing Stream Crossings ' There are three existing stream crossings in Section 1 of this project . The . flow of Mill Creek (Auburn) is carried under SR 167 by the following culverts : Sta. 504+50 2 - 10' X 6' Twin concrete box culvert Sta. 615+50 8' X 6' Concrete box culvert Sta. 691 +00 2 - 7 ' X 8' Twin concrete box culvert SR 167 crossing of Green River is used as a dividing point between Section 1 and Section 2 of this project. The bridge information is shown further in this report . Mill Creek (Auburn) is considered as a year- round stream. ' Existing Culverts There are existing culverts in Section 1 of this project located as follows : Sta. 534+25 SD50 24"m 25% plugged ' Sta. 541 +00 SD32 36"o Owned by City of Auburn 6 Sta. 556+50 SD62 24"o 100% plugged Sta. 573+50 SD64 12"o 50% plugged ' Sta. 585+40 SD67 24"o Clear ' Sta. 662+00 SD98 24"o Clear Sta. 638+33 SD92 30"o Clear ' Sta. 645+50 SD96 24"0 Clear Sta. 647+60 SD94 24"0 No information available , Sta. 662+00 SD98 240 Clear Sta. 684+50 SD106 240 No information available , Sta. 707+20 SD111 41 "X 4 ' Clear , Sta. 723+00 SD128 24 0 No information available Sta. 748+55 SD138 30"o No information available ' Sta. 757+50 SD141 18110 Clear Note "No information available" means that ends of pipes are not , accessible to inspection. Only major existing culverts are listed. There are numerous , other culverts at interchanges under various ramps . These can be summarized as follows : 15th St . S . W. Interchange - SD18, SD20 t SR18 Interchange - SD17, SD37 , SD38, SD51A, SD34, SD39, SD35, SD52A, SD29 , SD56, SD38A. 15th St. N. W. Interchange - SD73 , SD74, SD71 , SD82, SD85 . S . 277th St . Interchange - SD113 , SD114, SD123 , SD132 . ' There are parallel culverts in Section 1 . Only culverts for Mill Creek (Auburn) are listed below. As mentioned above there are other existing culverts under interchanges which are also adequately shown on drainage plans . 15th St. Southwest 10 ' X 6' Concrete Box Culvert ' SR 18 Bridge No information available West Main Street 3 - 10 , X 7 ' Triple Concrete Box Culvert ' 15th St . N.W. 8' X 6' Concrete Box Culvert ' 7 ' ' 37th St. N.W. 2 - 6, X 7' Double Concrete Box Culvert S. 277th St. 2 -610 & 2-810 Corrugated Metal Pipes ' The only private culvert belongs to the City of Auburn and is mentioned above. There are pipe outfalls in Section 1 of this project. Besides the stream culverts which also can be classified as pipe outfalls, there are other outfalls summarized as follows : ' N. E. Sta. 11 +50 SD37 18"0 S . E. Sta. 29+50 SD34 18"o ' S . E. Sta. 31 +75 SD35 24"o ' Sta. 534+50 SD50 24"o Sta. 556+50 SD62 24"o ' Sta. 585+40 SD67 24"o AR2 Sta. 15+50 SD71 18"o AL2 Sta. 6+50 SD74 811 0 DL2 Sta. 13+00 SD85 18"0 DR2 Sta. 10+75 SD82 18"o Sta. 638+33 SD92 30"o Sta. 645+25 SD96 24110 Sta. 662+00 SD98 24"o Sta. 684+50 SD106 24"o Sta. 707+20 SD111 41X4' Sta. 708+50 SD114 18"o ' DL1 Sta. 14+10 SD123 18"o ' DR1 Sta. 17+00 SD132 12"o FR1 Sta. 21 +65 SD134 24"o Sta. 748+55 SD138 30"o FR1 Sta. 47+75 SD139 30"o ' Sta. 757+50 SD141 18"o 8 Although the surveyed invert elevations do not support it, SD96 flows from west to east . ' Existing Ditches The original plans for construction of SR 167 call for Special , Ditch A to be constructed in various locations along the east or west side of the freeway . Visual inspection revealed that these ' ditches are no longer evident and need to be redefined and cleared of vegetation. This work will be accomplished by the proposed biofiltration ditches for almost entire length of Section 1 . Existing Subsurface Drainage There seem to be no subsurface drainage problems in this part of ' the project . See Soils Report for more details . Existing Bridges , Number Name Span Type 167/110 15th St . S .W. Undercrossing C Box , 167/112E SR-18 Overcrossing PCB 167/112W SR-18 Overcrossing PCB 167/115 W. Main St . Undercrossing C Box , 167/116 15th St . N.W. Undercrossing PCB 167/117 37th St . N.W. Undercrossing PCB ' 167/119 S . 277th St . Undercrossing PCB 167/121E Green River C Box-PCB ' 167/121W Green River C Box-PCB The only bridge with bridge drains is Green River bridge. It has one drain for southbound and one for northbound traffic. Neither of them is affected by this project. , 3 . 2 Section 2 General ' In Section 2 of the project, the drainage of the median and shoulders of the freeway is basically the same as in Section 1 . The next drainage structure is a 24-inch diameter pipe at Sta. 796+65, just before the interchange with SR 516, and then an 18- inch diameter pipe at Sta. 8"10+00, after the interchange. The ' first pipe carries water from west to east and the second one 9 ' carries water from east to west of the freeway. Just before SR ' 167 crosses over the Chicago Milwaukee St. Paul & Pacific Railroad, there is an 18-inch diameter pipe with uncertain direction of flow and, just after the railroad crossing is a 24- inch diameter pipe at Sta. 845+70 with flow from west to east. Shortly after the railroad crossing there is another 18-inch diameter pipe at Sta. 855+40 with flow from west to east. ' The last drainage structures in Section 2 are a 54-inch diameter pipe at Sta. 884+65 which carries water from the east side of the freeway over to the west side and a combination of pipes with ' different sizes at Sta. 891 +65 . Existing Flood Plains ' In Section 2 of this project SR 167 does not lie in any flood plain and it is only adjacent for very short stretch to Green River flood area and Mill Creek (Kent ) flood area. ' Starting at Green River SR 167 is protected from this river by T.S . Russell Road along its west side from Green River to the interchange with SR 516 . The next instance of being close to flood plain comes after crossing CMSt. P&P Railroad. This flood area has an elevation of ' 33 . 00 . Between BN Railroad overcrossing and the 84th Ave. S . interchange ' the freeway comes close to Mill Creek (Kent) flood plain along its east side . The elevation of this flood area is at about 32 . 00 . The stream flows under the freeway from east to west and only stream bed is designated as floodway area. Existing Stream Crossings ' There is only one stream crossing in Section 2 of this project. The flow of Mill Creek (Kent) is carried under the freeway by two 48-inch dia. pipes located at Sta. 884+30 . There are no stream ' crossings in this section using bridge structures . The Mill Creek (Kent ) is considered a year-around stream. Existing Culverts ' Besides the culvert carrying Mill Creek (Kent) there are other cross-culverts in this section located at : Sta. 796+50 SD 165 2411 0 33% plugged Sta. 809+90 SD 187 18"o 33% plugged ' Sta. 840+50 SD 205N 18if0 75% plugged Sta. 844+73 SD 206N 24"o No information available ' 10 Sta. 854+00 SD 212 2 - 48"o 25% plugged 84th Sta. 45+44 SD 366 36"o Clear , 84th Sta. 42+50 SD 240A 24"m Clear ' 84th Sta. 42+50 SD 240 24"o Clear Other culverts in Section 2 of this project are located under ' various ramps at interchanges with SR 516 and with 84th Ave. S . These can be summarized as follows : SR516 Interchange - SD169, SD169A, SD170, SD171 , SD172, SD175, ' SD176, SD178 . 84th Ave. S . Interchange - SD240A, SD243, SD365, SD360, SD358 ' There are no private road approaches nor private culverts . Besides Mill Creek (Kent) culvert there are other pipe outfalls ' within Section 2 limits which can be summarized as follows : Sta. 796+50 SD165 24"o ' AR2 Sta. 100+100 SD169A 18"o AL2 Sta. 101 +25 SD171 12"o , Sta. 809+90 SD187 18"o Sta. 840+50 SD205N 18"o ' Sta. 844+73 SD 206N 24"o Sta. 854+00 SD212 2 - 48"o ' 84th Sta. 42+50 SD240A 24"o ' DL1 Sta. 895+50 SD360 18"o DR1 Sta. 893+00 SD358 18"o ' 84th Sta. 41 +40 . 7 SD364 12"o 84th Sta. 41 +80 SD365 12"o , A power pole has been installed through the north end of SD 206N , rendering this culvert unusable and causing flooding of areas south of here . This deficiency must be corrected. Another problem is created by SD 169A which has outlet higher ' than inlet and both are about 1 foot higher than outlet elevation from SD 169 . To remedy this problem it will be necessary to remove SD169A, install a new pipe of the same size with lower 11 , invert elevations and regrade OC14 to drain the runoff to the ' inlet of SD169 . Existinq Ditches ' There are no roadside ditches in Section 2. Existing Subsurface Drainage There are no known subsurface drainage problems . See Soils Report for more information. Existing Bridaes There are bridge crossings within Section 2 limits with the following data: 167/122E SR 516 Overcrossing PCB ' 167/122W SR 516 Overcrossing PCB ' 167/123E Meeker St. Overcrossing PCB 167/123W Meeker St . Overcrossing PCB ' 167/124E James St . Overcrossing PCB 167/124W James St. Overcrossing PCB ' 167/12SE UP Railroad Overcrossing PCB ' 167/125W UP Railroad Overcrossing PCB 167/126E 4th St. Overcrossing PCB 167/126W 4th St . Overcrossing PCB 167/127E BN Railroad Overcrossing PCB ' 167/127W BN Railroad Overcrossing PCB 167/128E 84th Ave . S . Overcrossing* PCB ' 167/128W 84th Ave . S . Overcrossing* PCB ' ( * SR 167 Old Alignment) Due to bridge widening, bridge drains will need to be relocated at Bridge No . 167/127W, Bridge No. 167/125W, Bridge No. 167/124W, ' Bridge 167/123E and Bridge 167/123W. 3 . 3 Section 3 General 12 The first structure in Section 3 of the project is a 42-inch diameter pipe at Sta. 909+50 with an east to west flow serving as ' a conduit for Springbrook Creek (P-1 Channel ) . Further north is an 18-inch diameter pipe at Sta. 916+00 which carries water from the east side of the freeway to the ditch on the west side. This ' ditch is connected to Springbrook Creek via drain pipe -SD265A.The ponding in the ditch between SR 167 and Frontage Road is relieved by a series of 8-inch diameter pipes at Sta. 921 with flow from west to east. The great number of pipes shown on the plans indicates a low headroom problem in this area. An 18-inch diameter pipe located at Sta. 928+65 takes the water from east to west . The next 18-inch diameter pipe at Sta. 935+25 is flowing ' in the same direction. At the same station, the plans show Springbrook Creek to be again adjacent to the west side of the freeway. ' South of the interchange with the South 212th Street undercrossing, there is a 48-inch diameter pipe at Sta. 943+10, serving as a culvert for Garrison Creek flowing from the east to ' the west side of the freeway and into Springbrook Creek. This 48-inch pipe also picks up the drainage from the entire southeast portion of the interchange. The west side of the interchange , drains directly into Springbrook Creek. Once on the other side of the bridge, we encounter an 18-inch diameter pipe with the flow from east to west at Sta. 951 +00 . In front of the South 208th Street undercrossing is a 24-inch diameter pipe at Sta. , 960+30 and after the bridge is an 18-inch diameter pipe at Sta. 962+50, both with the flow from east to west . Both pipes are connected directly to Springbrook Creek which still follows the t west side of the freeway. Near Sta. 969+00 is the beginning of an area with an underground ' water problem. At this station the_ plans show an 8-inch diameter perforated pipe located at the centerline of the median and further north a similar pipe runs along the east shoulder of the freeway . The water collected by the perforated pipes is carried ' to the west side of the freeway by a 12-inch and 18-inch diameter pipes located at Sta. 969+00 , Sta. 974+60, Sta. 984+50, Sta. 989+50 , Sta. 994+05 and Sta. 997+15 . An enclosed pipe system , along east side of SR 167 starts at Sta. 969+00 , has a manhole at Sta. 974+60 and ends at Sta. 987+20 . The perforated pipe in the middle of the median ends at Sta. 994+10 and starts again at Sta. 1004+35 . There is an 18-inch diameter pipe across the freeway at ' Sta. 1002+90 with east to west direction of flow. Springbrook Creek that follows the west side of the freeway takes a sharp turn left towards the west at Sta. 1001 +00 . t After the beginning of another length of the 8-inch diameter perforated pipe in the median at Sta. 1004+35 , we enter a part of t the freeway with numerous drain pipes installed mainly under the northbound lanes . Pipes across the freeway are located in Sta. 1006+00, Sta. 1009+10 and Sta. 1013+80 . The perforated drain pipe at the centerline median terminates at Sta. 1012+00 . A 48- , inch diameter pipe provides drainage conduit for a creek without 13 , 1 name from east to west at Sta. • 1014+85 . This creek then flows ' along the west side of the freeway heading north. Another series of pipes across the freeway is subsequently located at Sta. 1018+00 ( 12-inch dia. ) , Sta. 1024+50 ( 24-inch dia. ) , Sta. 1030+00 ' ( 24-inch dia. ) and Sta. 1041 +85 ( 30-inch dia. ) . The creek- without name turns sharply west at Sta. 1040+40 . As the roadway approaches the South 180th Street undercrossing, there are no major drainage structures crossing the freeway except the usual drains from the median. The interchange is at the limits of the City of Kent and Renton and is also known as S .W. 43rd Street on the Renton side. The traffic barrier in the median starts right after the bridge at Sta. 1056+00 with the northbound edge of the pavement extending under the barrier to support it . Coming out of the interchange, the ditch formed ' along the east side is taken across the freeway to the west side by a 24-inch diameter pipe at Sta. 1071 +10 . The flow from this pipe continues north in an open channel to Sta. 1075+80 at which point a flow from another pipe across the freeway i.s added and the open channel turns sharply west. Along the east side of SR 167 , we have now come to Panther Creek ' Wetland. A series of pipes provides relief for the wetlands to drain to the west side of the freeway . These pipes are located at Sta. 1081 +80 ( 48-inch dia. ) , Sta. 1083+90 ( 36-inch dia. ) , Sta. ' 1086+20 ( 30-inch dia. ) , Sta. 1091 +70 ( 48-inch dia. ) Sta 1101 +80 ( 48-inch dia. ) , Sta 1106+90 ( 30-inch dia. ) and Sta. 1115+00 ( 30- inch dia. ) . ' As the roadway approaches the interchange with SR 405 which has a number of drainage structures and as indicated on the plans available. There is a station equation at Sta. 1128+00 = Sta. ' EE975+00 . There is a 3' x 4' culvert transferring the flow from east to west at Sta. EE989+30 . This culvert carries water for about 70% of the entire interchange. An 18-inch diameter pipe at ' Sta. EE1005+40 is a part of the interchange system with the flow from west to east and is the last drainage structure on this project. ' Existing Flood Plains In Section 3 SR 167 is adjacent to several flood plain areas . Starting at interchange with 84th Ave . S . the northbound on-ramp is adjacent to Springbrook Creek flood plain classified as flood area with flood elevation of 30 . 0 . Springbrook Creek crosses SR ' 167 at Sta. 909+50 and from this station up to Sta. 1048+00 the southbound lanes of SR 167 are adjacent to the creek' s flood plain classified as flood area with flood level changing gradually from elevation 29 . 0 at south to elevation 23 . 0 at ' north . At southwests corner of the interchange with S . 180th St. is a ' small flood area without apparent source with flood level at elevation 18 . 0 . North of this interchange the northbound lanes 1 14 are adjacent to Panther Creek Wetland with flood level at elevation 16 . 0 . This flood area extends all the way to the SR ' 167-SR 405 interchange which is the end of this project. Existing Stream Crossings ' There are existing stream crossings in Section 3 of this project. Following south to north order SR 167 is crossing Springbrook Creek, Garrison Creek and a creek without name at these stations : ' Sta. 909+50 42"o Reinf. Concrete Culvert Clean Sta. 943+11 2-48"m Reinf. Concrete Culvert Clean i Sta. 1014+85 48"o Metal Pipe, 12 GA 25% plugged The Panther Creek Wetland is drained across SR 167 with numerous ' culverts listed under the following paragraph. SR 167 does not cross any streams using bridge structures but the following ramps which are part of the interchange with S . 212th St. cross streams as shown: Number Name Span Type ' 167/129 E-S E-S Ramp over Springbrook Creek CS 167/129 N-E N-E Ramp over Garrison Creek CS ' 167/129 S-W S-W Ramp over Springbrook Creek CS ' All three streams and outlets from Panther Creek Wetland are considered year-around streams . Existing Culverts The following culverts are in existence under SR 167 in addition ' to those listed above : Sta. 916+00 SD265 18"o Clean Sta. 928+65 SD267 18"o No Information Avail . , Sta. 935+25 SD269 18"o Clean Sta. 951 +00 SD271 180 Clean Sta. 960+20 SD329 24"0 Clean ' Sta. 962+50 SD275 18"o Clean Sta. 969+00 SD278 12if0 Clean Sta. 974+50 SD279 18"o Clean ' 15 , 1 Sta. 984+50 SD280 18"o Clean Sta. 989 . 50 SD281 18"0 Clean ' Sta. 994+00 SD282 12110 Clean Sta. 996+90 SD293 18"0 Clean Sta. 1002+90 SD284 18"0 Clean Sta. 1006+00 SD285 12"o Clean Sta. 1009+12 SD287 18"o Clean ' Sta. 1013+80 SD289 18"o Clean Sta. 1015+50 SD381 12110 Clean Sta. 1018+00 SD291 18"o Clean Sta. 1024+50 SD292 24110 Clean ' Sta. 1030+00 SD293 24110 Clean ' Sta. 1041 +80 SD294 30"o Clean, submerged Sta. 1050+00 SD297 18"o 75% plugged ' Sta. 1071 +05 SD302 24110 Clean Sta. 1075+90 SD303 30"o Clean ' Sta. 1081 +80 SD305 12110 100% plugged Sta. 1083+80 SD306 36"o 100% plugged Sta. 1086+14 SD307 30"o 100% plugged Sta. 1091 +70 SD308 48"o Clean Sta. 1101 +70 SD309 48"o Submerged ' Sta. 1107+00 SD310 36"o 100% plugged Sta. 1115+00 SD311 24110 Clean Sta. EE980+00 SD404 12110 Not Found Sta. EE984+10 SD410 12110 Clean Sta. EE989+00 SD511 3' X 4 ' No Information Available ' Sta. EE1005+35 SD464 18110 No Information Available ' 16 Only major culverts are listed. There are numerous other culverts at interchanges under various ramps . These can be summarized as follows : S . 212th St. Interchange SD506, SD507 , SD324A . S . 180th St. Interchange SD347 , SD301 ' SR405 Interchange SD513, SD514, SD466, SD515, SD516, ' SD466A, SD517, SD518, SD512, SD519, SD466, SD520 , SD521 There are parallel culverts in Section 3 as follows : Sta. 913+95 SD265A 72"o Sta. 914+68 SD265B 18"c , Sta. 943+25 SD435 18"o Sta. 948+43 . 66 Not labeled 36"o DL2 Sta. 63+40 301 18"o ' Beside creek crossing culverts, there are other pipe outfalls within Section 3 of this project, which can be summarized as ' follows : Sta. 9.16+00 SD265 18"e Sta. 928+65 SD267 18"o Sta. 935+25 SD269 18"o , Sta. 951 +00 SD271 18"o Sta. 960+20 SD329 24"o Sta. 962+50 SD275 18"m Sta. 969+00 SD278 12"o i Sta. 974+60 SD279 18"o Sta. 984+50 SD280 18"o Sta. 989+00 SD281 12"o Sta. 994+00 SD282 18"o Sta. 996+90 SD283 18"o ' Sta. 1002+90 SD284 18"o 17 , Sta. 1006+00 SD285 12"o Sta. 1009+12 SD287 18"o Sta. 1013+80 SD289 18"o Sta. 1015+50 SD381 12"o ' Sta. 1018+00 SD291 18"o Sta. 1024+50 SD292 24"o Sta. 1030+00 SD293 24"o 1 Sta. 1041 +80 SD294 30"o Sta. 1050+00 SD297 18"o ' DR2 Sta. 66+13 SD347 12"o Sta. 1071 +05 SD302 24"o ' Sta. 1075+90 SD303 30"o ' Sta. 1081 +80 SD305 12"o Sta. 1083+80 SD306 36"o 1 Sta. 1086+14 SD307 30"o Sta. 1091 +70 SD308 48"o Sta. 1101 +70 SD309 48"o Sta. 1107+00 SD310 36"o Sta. 1115+00 SD311 24"o ' EE Sta. 980+00 SD404 12"o EE Sta. 984+10 SD410 12"o EE Sta. 989+00 SD511 3' X 41 AR2 Sta. 85+90 SD513 18"o DR2 Sta. 85+38 SD466 48"o BL2 Sta. 79+00 SD518 18"o AR2 Sta. 81 +30 SD514 18"o Existing Ditches 1 18 There are roadside ditches within Section 3 of this project. They were observed and are in need of maintenance . Existing Subsurface Drainage ' The existing subsurface drainage has been described in the general part of Section 3. For more information also see Soils Report. ' Existing Bridges Number Name Span Type ' 167/129 S . 212th St . Undercrossing PCB 167/130 S . 208th St. Undercrossing PCB 167/133 S . 180th St . Undercrossing PCB Since all bridges in Section 3 are undercrossings, the existing , bridge drains are not effected by this report. 3 . 4 Other Projects There will be future developments along SR 167 which will impact the drainage of the area. In Section 1 , the City of Auburn plans a new development east of SR 167 between Main Street West, 15th ' Street N.W. and the railroad tracks, and another development east of SR 167 between South 285th Street and South 277th Street which will include partial relocation of Mill Creek. The City of Kent Public Works Department has two projects planned within Section 2. One project considers improvements of the aquifer well and installation of an industrial wash sewer pipe in the vicinity of the interchange with SR 516 . The other project addresses discharge of drainage under the Green River, west of the SR 516 interchange . In Section 3, the City of Renton has several projects in the planning stages . The city is proceeding with P-9 Channel design to improve Panther Creek Wetland and will request all new and ' existing culverts crossing SR 167 to be capped off. The city will also request addressing of the flooding problem near Nendels Motel which will be made worse by SR 167 widening. There will also be a future sewer and water line crossing SR 167 between SR 405 and S .W. 43rd Street . Our site inspection revealed that some drainage structures shown ' on the plans were not constructed at all or where submerged below the water and therefore could not be identified. Approximately half a dozen structures were built within a 100 foot range from locations shown on the plans . About 40 catch basins shown on the plans were not installed, probably because they were not needed under the specific conditions . 19 1 r The main observation made was that the majority of the drainage ' structures are plugged or reduced in capacity by sediments and debris . We recommend that the structures be cleaned, including those requiring no work, prior to construction of this project and then a program be made for regular maintenance of the drainage facilities . 20 4 . 0 PROPOSED IMPROVEMENTS , The project proposes to widen the northbound and southbound lanes towards the median, but at numerous locations main roadways and ' ramps are widened on the outside . Figures A, B, C, and D in the Appendix show conditions of the widening at different intervals of SR 167 . These figures show prevailing conditions within each section and not the specific conditions at each curve and in transitions . Due to the complexity of this project it is necessary to describe proposed improvements for each section separately. 4 . 1 Design Criteria A. Design Storm Frequency - Interstate Structure (All storms shall have 24-hour duration except , for 100-year storm) B. Conveyance - Rational Method - Post Development ' Catch Basins . . . . . . . . . . . . . . . . . . . . . . . 10 yr. Storm Sewers - Trunk. . . . . . . . . . . . . . . 25 yr. ' - Laterals . . . . . . . . . . . . 10 yr. - Inlets . . . . . . . . . . . . . . 10 yr. , Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 yr. , Ditches . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 yr. Gutters, 51 . . . . . . . . . . . . . . . . . . . . . . . . 10 yr. ' Depressed Roadways . . . . . . . . . . . . . . . . . 50 yr. Culverts . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 yr. ' C. Detention - Santa Barbara Urban Hydrographic ( SBUH) Method Section 1 City of Auburn Release 2-yr Predevelopment Detention 25-yr Postdevelopment City of Kent Release 10-yr Predevelopment ( Zone No. 1 ) Detention 25-yr Postdevelopment-- Section 2 , City of Kent Release 10-yr Predevelopment ( Zone No. 2 ) Detention 82"X new impervious area City of Kent Release 10-yr Predevelopment ( Zone No. 3 ) Detention 25-yr Postdevelopment 21 ' 1 , ' Section 3 City of Kent Release 10-yr Predevelopment ( Zone No. 3 ) Detention 25-yr Postdevelopment City of Renton Release 2-yr Predevelopment Detention 10-yr Postdevelopment D. Water Quality - Biofiltration 2-yr. Oil/Water Separators 10-yr. E. Rainfall Precipitation 2-year storm. . . . . . . . . . . . . . . . . 1 . 9 inches ' 10-year storm. . . . . . . . . . . . . . . . 2 . 95 inches 25-year storm. . 3 . 35 inches 50-year storm. . . . . . . . . . . . . . . . 3 . 5 inches 100-year 24-hour storm. . . . . . . 3 . 9 inches 100-year 7-day storm. . . . . . . . . 9 . 8 inches F. Runoff Coefficients for SBUH ' Impervious Surface. . . . . . . . . . . . . . . .CN = 98 Pervious Surface . .CN = 85 (Based on average soil type B) G. Runoff Coefficients for Rational Method Impervious Surface . . . . . . . . . . . . . . . .0 = . 9 Pervious Surface . .0 = . 3 H. "n" values Ditches - conveyance and velocity (slope = 2%) n = . 027 - conveyance & velocity (slope <2%) n = . 1 - biofiltration n = . 35 ' Storm Sewers - concrete pipe n = . 024 - corrugated metal pipe n = . 024 I . Design Methods WSDOT Programs - Open Channels and Ditches - Enclosed Systems ' - Culverts - Gutters - Inlets at sag locations ' SBUH - Detention and Release J. Pre-development Condition - SR 167 pavement configuration ' prior to widening. Post-development Condition - SR 167 pavement configuration after widening is completed 22 4 . 2 Design References ' WSDOT Design Manual, Section 1210 WSDOT Highway Hydraulic Manual , WSDOT District 1 Hydraulic Report Guide WSDOT Standard Plans and Specifications City of Renton Requirements (See Appendix) ' City of Kent Requirements (See Appendix) City of Auburn Requirements ( See Appendix) King County Surface Water Design Manual Eastside Green River Watershed Plan ' 4 . 3 Section 1 General ' There will be two conditions created by the widening in Section 1 ' of the project . The first condition is shown in Figure A indicating that even after widening of the northbound and southbound lanes there will be ample median left in-between. Therefore the existing drain pipes and catch basins located in , the median need not be modified except for their cleaning. Since for most part of this section the freeway runs straight the standard crown slopes the pavement to the outside edge. Therefore the attractive grass area in the median cannot be used for treatment of the runoff. The second condition in Section 1 occurs where the existing , median narrows down and will cease to exist after northbound and southbound lanes are widened. This will not change the routing of runoff since most of the runoff is directed by the crown slope towards the shoulders . The embankment of the freeway in Section 1 is rather low with the ' roadway being elevated four to six feet above the adjacent land with exception of the approach to Green River Bridge. The conditions between the toe of the embankment and WSDOT right-of- way vary from flat to small ponds with standing water to ditch ' profiles to shallow open channels with various velocity of the water. Outside of the area immediately next to shoulder where growth of vegetation is controlled by WSDOT there is abundance of , grass providing biofiltration of the runoff . In most places it is impossible to separate marshes and ponds on adjacent land from those located within the right-of-way . Alternative A 1 In order to separate highway runoff from off-site runoff it is , proposed to build an obstacle to prevent the highway runoff spilling over the right-of-way line . The form of the obstacle would depend on available space between the toe of the embankment and the right-of-way line . In areas of ample space the obstacle would be a form of an impermeable earth berm forming the outer edge of a biofiltration swale . As the available space narrows this earth berm would change into a ditch with the outer side ' 23 ' 1 e. 1 lined with rip-rap which in turn might change into a concrete ' wall. Ultimately because of lack of space we maybe left with two alternatives; leave the status quo or tie highway runoff into a closed pipe system. Alternative B The berms and ditches proposed in Alternative A will have impacts on wetlands, floodways, and floodplain over substantial length of Section 1 of this project. ' Alternative B is proposed to reduce these impacts . Under Alternative B, these berms and ditches would not be constructed. Instead, the existing natural system would be preserved and would ' be used for a bi_ofiltration of the stormwater runoff before this runoff reaches streams or a groundwater table . The detention of the stormwater runoff would be reduced to detention pipes and ponds shown in Alternative A. Streams The major stream in Section 1 is Mill Creek (Auburn) with Basin 1 1 , 2 and 3 as shown on pages 56, 57 and 58 of this report. Due to the size and complexity of these basins tributary to Mill Creek (Auburn) , design flows for this creek were not calculated. ' Since we are limiting the release of the stormwater runoff from the project area into Mill Creek (Auburn) to the predevelopment amount and since King County or City of Auburn did not indicate there are any flooding problems caused by the present culverts carrying Mill Creek (Auburn) across SR167, no enlargement of these culverts or additional culverts for this stream are ' proposed. However, what is known to King County is the inadequacy of the culvert carrying Mill Creek (Auburn) flow under S . 277th St. adjacent to this project . There are no new stream crossings proposed for Section 1 of this project nor is any existing stream in need of adding rip-rap to its bank protection . The impact of widening of SR 167 in Section 1 on Mill Creek (Auburn) will be mitigated by releasing 2-year storm predevelopment flow from the project while detaining 25-year storm postdevelopment flow. Flood Plain ' In Section 1 this project will affect the Mill Creek (Auburn) flood plain since the proposed berms which will separate roadway ' runoff from private lands will be mostly built in the existing flood plain areas and in several instances also in the hydraulic floodway. The drainage plans indicate 100-year flood levels . See these plans for encroachments of the project into the floodplain. The berms will change the flooding cross section area by less than 1 % . 24 .. 1 Several ramp widenings will also result in the encroachment ' either into flood areas or floodways . Nevertheless the amount of all added fill is so small compared to the large flood areas that the flood level is going to be raised less than . 01 ' , therefore the impact on the flood plain elevation at the ramp is non- significant. Channel Changes There are no channels located in Section 1 of this project. Culverts ' The culverts carrying flora of Mill Creek (Auburn) across SR 167 need not be modified. New culvert installation is proposed at the following locations : Sheet 14 Sta. 661 +75 24"o west to east flow Sheet 21 Sta. 767+00 24"o west to east flow There are no proposed interchange or private road culverts . The following culverts will remain as outfalls : SD37 , SD34, SD35, SD50, SD62, SD67 , SD92, SD98, SD106, SD111 , , SD114, SD123, SD134, SD138 & SD139 . The following culverts will be intercepted by the proposed biofiltration ditches : SD71 , SD74, SD132 & SD141 . Culvert End Sections Standard Plan B-9 headwalls with heavy loose rip-rap are proposed for the new culvert to be installed at Sta. 661 +75 . Ditches open ditches will be used extensively in Section 1 of this , project either as an improvement to the existing Special Ditch A or as new installations to provide biofiltration treatment. The ditches in Section 1 can be divided into the following categories : a. Ditches with slopes > 20 : For the first 200 L.F . from an outlet or a flow control structure the ditch is sized for biofiltration or detention ' whichever controls . The remaining length is sized for conveyance and velocity . The entire length of the ditch will be grass-lined. 25 ' b. Ditches with slopes <2%: ' For the first 200 L.F. from an outlet or a flow control structure the ditch is sized for biofiltration as a wetland or detention whichever controls . The remaining length is ' sized for conveyance and velocity. The entire length of the ditch needs to be seeded with riparian plantings . Light loose or heavy rip-rap or quarry spalls are proposed at ' points where pipes and culverts tie into the ditches to prevent erosion. The proposed ditches are accompanied in numerous instances by berms to keep the roadway runoff within the right-of-way . For information related to the width at the top of the berms to facilitate access for the maintenance crews see Sheet 63 . Enclosed Drainage There are enclosed drainage systems proposed in Section 1 of this project . These systems can be summarized as follows : Sheet 6 LM Sta. 536+50RT to LM Sta. 537+OORT ' Sheet 6 LM Sta. 538+50RT to LM Sta. 539+OORT Sheet 7 LM Sta. 543+OORT to LM Sta. 544+90RT Sheet 17 LM Sta. 703+40LT to LM Sta. 705+90LT ' Sheet 18 DR1 Sta. 18+99 RT to LM Sta. 723+00 RT Sheet 21 LM Sta. 758+75LT to LM Sta. 762+50 LT There are no storm or sanitary sewers that belong to other jurisdictions that will be affected by this project. Gutter Design Concrete curb and gutter will not be used in Section 1 of this project . Asphalt curb is required in Section 1 of this project to control slope erosion at the following locations : ' Sheet 5 WN Ramp SR 18 Interchange Sheet 5 , 6 & 7 EN Ramp SR 18 Interchange Sheet 10 AL2 Ramp 15th St . N.W. Interchange Sheet 10 DR2 Ramp 15th St . N.W. Interchange Sheet 18 & 19 DR1 Ramp S . 277th Interchange 26 1 Sheet 18 AL1 Ramp S . 277th Interchange Sheet 21 & 22 L Sta. 766+DOLT to L Sta. 773+60LT (exist . curb) Sheet 21 & 22 L Sta. 766+OORT to L Sta. 773+55RT (exist. curb) ' Asphalt curb will be served by Type 1 or in some instances Type 2 catch basins and 12-inch dia. pipe Detention Detention ponds in Section 1 of this project will be provided as ' part of biofiltration swales which will be restrained by flow control structures . These swales will be designed to store 25- year postdevelopment storm flow with 2-year predevelopment storm ' release. The flow control structures are proposed at the following locations : Sta. 504+00 RT EN Sta. 34+00 RT ' Sta. 534+70 RT Sta. 540+55 LT Sta. 545+00 RT , Sta. 556+00 RT Sta. 556+25 LT Sta. 585+00 RT Sta. 585+25 LT Sta. 586+00 RT AL2 Sta." 8+00 LT Sta. 614+75 LT ' Sta. 615+15 LT Sta. 615+75 RT Sta. 616+25 RT Sta. 638+00 LT Sta. 638+00 RT Sta. 661 +50 LT Sta. 661 +50 RT ' Sta. 684+25 LT Sta. 684+25 RT Sta. 690+25 RT ' Sta. 691 +00 LT Sta. 691 +50 LT Sta. 703+40 LT AR1 Sta. 7+00 RT DR1 Sta. 18+99 RT Sta. 723+15 RT 27 Sta. 724+00 LT Sta. 748+25 LT ' Sta. 748+75 LT Sta. 748+85 RT Sta. 749+40 RT ' Some doubts were raised by the City of Auburn to the usage of biofiltration facilities for detention but due to gentle slopes present in Section 1 even 25-year storm produces low velocities. ' An alternative solution to the detention problem, the City of Auburn offers to drop requirements for detention in exchange of WSDOT financial participation in the planned regional retention ' ponds adjacent to SR 167 . These future projects are discussed elsewhere in this report . No retention ponds are proposed for this project in Section 1 . Subsurface Drainage ' Subsurface drainage is not required in Section 1 of this project. For more information, see Soils Report . ' Existing Utilities There are numerous existing utilities crossing SR 167 in Section 1 , but we are not aware at this moment that any will interfere ' with the proposed drainage. Water Quality A water quality assessment was not done for this project. The intent is to install biofiltration swales almost throughout the entire Section 1 of the project . The length of the biofiltration ' swales was limited to 200 linear feet minimum to reduce the cost of the project . The biofiltration swales with the slopes less than 2% were designed as wetlands with riparian vegetation. The ' %^-PS & E drainage plans need to coordinate the installation of this vegetation with the landscaping plans . ' At places where no widening of the existing lanes is planned, we propose to install Type 2 catch basins with a tee oil/water separator to enhance the quality of water leaving SR167 . ' Fish and Wildlife Requirements The requirements of the Department of Fisheries Hydraulic Project Approval permit are: 1 . Detention - Release 500 of 2-year predevelopment Detention 2-year postdevelopment ' - Release 25-year predevelopment Detention 25-year postdevelopment 28 2 . Water Quality - Biofilter swales - 2-year storm ' - Velocity less than 1 . 5 fps - Flow depth less than 4 inches - Slope average 2% to 4%* - Min. length 200 ft . ' - Side slopes 3H: 1V or less *Due to the flatness of the terrain, this criteria cannot be met. The swales with the slope less than 2% are designed as wetlands with riparian plantings . For sample Hydraulic Project Application Form, see Appendix. ' Other Permits SEPA ' Department of Ecology Corps of Engineers , City of Auburn City of Kent Pipe Alternates , PH and resistivity tests were performed for this project and resulted in the following values : ' PH = 6 Resistivity = 5, 000 to 30 , 000 ohm-cm This project is located in Corrosion Zone 2 . The information shown on the plans is based on using concrete ' pipe. Acceptable alternates for STORM SEWER PIPE are: Galvanized Steel Storm Sewer Pipe: , - Tr. 5, . 064" thick. Tr. 2 with welded or gasketed longitudinal seams, . 064" thick diameter 3 inches longer than specified. Aluminized Steel Storm Sewer Pipe : , - Tr. 5, . 064" thick. - Plain with gasketed or welded and remetalized longitudinal seams, . 064" thick, diameter 3 inches longer than specified. Aluminum Storm Sewer Pipe : - Tr. 5, 060" thick. , - Plain with gasketed longitudinal seams, . 060" thick, diameter 3 inches larger than specified. Spiral Rib Storm Sewer Pipe : ' - Plain aluminum or plain narrow pitch aluminum, . 060" thick. - Plain aluminized steel or plain narrow pitch aluminized steel, , . 064" thick. 29 1 . i Tr. 2 galvanized steel or Tr. 2 narrow pitch galvanized steel, . 064" thick. For CULVERT SCHEDULE PIPE ( Standard Plan B-17 ) , the following note should be added to the structure note sheet: - Galvanized Steel Alternate shall have Treatment 2 . Acceptable alternates for DRAIN AND UNDERDRAIN PIPE are listed in the standard specifications . No treatment is required and no additional notes are necessary on the structure note sheets . 1 1 1 1 1 1 1 r i 1 r r r r 30 1 4 . 4 Section 2 ' General In Section 2 the freeway crosses over numerous streets in ' the City of Kent and two sets of multiple railroad tracks and therefore runs on a high embankment. Yet on each side of the freeway are ditches with standing or very slowly ' moving water. In most instances the on-site (freeway) runoff is separated from the off-site drainage system. About half the length of the open channels is silted and overgrown with brush. Cleaning them and seeding will greatly improve their biofiltration capacity. Streams , The only stream in Section 2 is Mill Creek (Kent) . Design flows for this creek were not calculated. The impact of widening on Mill Creek (Kent) will be mitigated by releasing ' 10-year storm pre-development flow from the project while detaining 25-year postdevelopment flow. There are no new stream crossings proposed for this project in Section 2 . , Stream bank protection is not required. Flood Plain ' In Section 2 this project will not affect any existing flood plain. Channel Changes ' There are no channels located in Section 2 of this project . , Culverts The culvert carrying flow of Mill Creek (Kent) across SR 167 ' need not be modified. New culverts are proposed as follows : , Sheet 24 & 25 AR2 Sta. 97+15 24"0 Sheet 24 LSta. 799+60 24"0 Sheet 24 AL2 Sta. 98+80 24"0 Sheet 26 & 27 LSta. 840+50 36"0 Sheet 30 AL3 Sta. 93+OOLT 24110 There are no proposed private road culverts . r The following culverts will remain as outfalls : SD165 , SD169A, SD171 , SD187 , SD205N, SD212 , SD240A, SD360, SD358, ' SD364 and SD365 . 31 None of the existing culverts will be intercepted by the ' proposed biofiltration ditches . Culvert End Sections Standard Plan B-9 headwalls with heavy loose rip-rap are proposed for the new culverts . Ditches In Section 2 SR167 runs on a high embankment. This . embankment reduces space available between its toe and right-of-way to install new ditches . The new ditches are proposed wherever space is adequate in order to provide some biofiltration treatment. In some locations it is proposed ' to construct retaining walls to provide space for the ditch installation. The ditches with slopes = 2% will be grass- lined and the ditches with slopes <2% will be seeded with riparian plantings . Light loose or heavy rip-rap or quarry spalls are proposed at points where pipes and culverts tie into the ditches to prevent erosion. Enclosed Drainage There are enclosed drainage systems proposed in Section 2 of ' this project. These systems can be identified as follows : Sheet 22 & 23 L Sta. 777+25 LT to L Sta. 791 +00 RT ' Sheet 22 & 23 L Sta. 777+25 RT to AR2 Sta. 97+15 RT Sheet 23 L Sta. 794+00 LT to AL2' Sta. 96+00 LT Sheet 23 L Sta. 790+00 LT to L Sta. 790+00 RT Sheet 24 & 25 L Sta. 809+95 RT to L Sta. 813+12 RT Sheet 25 L Sta. 820+25 LT to L Sta. 823+25 LT Sheet '25 & 26 L Sta. 817+50 RT to L Sta. 828+00 RT Sheet 26 L Sta. 828+00 RT to L Sta. 831 +25 RT ' Sheet 26 L Sta. 828+00 LT to L Sta. 831 +25 LT Sheet 26 L Sta. 834+50 LT to L Sta. 837+75 LT Sheet 28 L Sta. 859+75 RT to L Sta. 861 +50 RT Sheet 28 L Sta. 862+10 LT to L Sta. 863+50 LT ' Sheet 29 & 30 L Sta. 877+30 RT to AR3 Sta. 87+00 RT Sheet 29 & 30 L Sta. 878+00 LT to AL3 Sta. 93+00 LT ' There are no storm or sanitary sewers that belong to other jurisdictions that will be affected by this project. Gutter Design Concrete curb and gutter will not be used in Section 2 of this project. Asphalt curb is required to control slope erosion at the following locations : 32 Sheet 22 & 23 L Sta. 773+55 RT to AR2 Sta. 94+00 RT ' Sheet 22, 23 & 24 L Sta. 773+60 LT to AL2 Sta. 100+65 LT Sheet 23 & 24 L Sta. 795+25 RT to, L Sta. 802+66 RT ' (Exist . Curb) Sheet 24 L Sta. 797+50 LT to L Sta. 802+70 LT (Exist. Curb) ' Sheet 24 & 25 SR516 Sta. 219+95 LT to L Sta. 814+65 RT Sheet 24 & 25 DL2 Sta. 9+00 LT to L Sta. 814+65 LT Sheet 25 L Sta. 814+65 LT to L Sta. 820+25 LT (Exist. Curb) ' Sheet 25 & 26 L Sta. 814+65 RT to L Sta. 828+00 RT Sheet 26 & 27 L Sta. 828+00 RT to L Sta. 845+90 RT (Exist. Curb) Sheet 27 & 28 L Sta. 847+83 LT to L Sta. 859+42 LT (Exist. Curb) Sheet 27 & 28 L Sta. 845+90 RT to L Sta. 861 +25 RT (Exist. Curb) , Sheet 28 & 29 L Sta. 859+42 LT to L Sta. 876+40 LT (Exist. Curb) Sheet 28 & 29 L Sta. 861 +25 RT to L Sta. 872+45 RT ' (Exist. Curb) Sheet 29 L Sta. 876+60 LT to AL3 Sta. 93+00 LT Sheet 29 & 30 L Sta. 876+40 LT to AL3 Sta. 93+00 LT ' Sheet 29 & 30 L Sta. 872+45 RT to AR3 Sta. 87+00 RT Sheet 30 L Sta. 886+50 RT to L Sta. 890+80 RT (Exist. Curb) Asphalt curb will be served by Type 1 catch basins and 12- inch diameter pipe. Detention ' From Green River to West Meeker Street the project is , located in the City of Kent Zone No. 2 . For this zone the City of Kent requires provisions for detaining 100-year storm with 7-day duration or simply providing storage for volume which equals proposed impervious area times 8 1 /2" . , According to the City of Kent this storage can be provided anywhere within the project and Zone No. 2 . We propose to provide this storage in the south pockets of the SR516 ' interchange . Between West Meeker Street and 84th Ave . North the City of Kent detention requirements ask for 25-year storm to be ' released at 10-year storm rate . There one area with downstream system capacity problem. This area is at James Street and it is shown on Sheet 6 . With 10-year release ' (and even with 2-year release) the City of Kent enclosed drainage system downstream from the point of discharge from SR167 right-of-way to open channel 53 is inadequate and ' needs to be upsized. Also, in this area we are proposing 33 L installation of a detention pipe while in all other areas of Section 2 and the City of Kent Zone No. 3 we are detaining storm water inside biofiltration ditches . The City of Kent does not see any problems with this technique. 1 No retention ponds are proposed for this project in Section 2 . The flow control structures (FCS ) are proposed at the following locations : ' Sta. 811 +75 RT Sta. 832+00 LT ' Sta. 844+00 LT Sta. 856+40 LT ' Subsurface Drainage Subsurface drainage is not required in Section 1 of this ' project . For more information, see Soils Report. Existing Utilities ' There are numerous existing utilities crossing SR 167 in Section 1 , but we are not aware at this moment that any will interfere with the proposed drainage . ' Water Quality A water quality assessment was not done for this project. The intent is to provide biofiltration swales wherever possible in Section 2 . The length of the biofiltration swales was limited to 200 linear feet minimum to reduce the cost of the project . The biofiltration swales with the lopes less than 2% were designed as wetlands with riparian vegetation. The PS & E drainage plans need to coordinate —the installation of this vegetation with the landscaping ' plans . In the following parts of Section 2 we feel that existing conditions are enhancing water quality better than if we proposed new biofiltration swales : ' a. Green River to SR516 Interchange - Storm water runoff from impervious surface is collected by enclosed drainage. b. SR516 Interchange - Large interchange pockets serve as sedimentation ponds . 34 c. James Street to 4th Ave . (right side of SR167 ) Existing wooded area with lots of grass is better than anything we could provide by ditch installation. , Fish and Wildlife Requirements The requirements of the Department of Fisheries Hydraulic ' Project Approval permit are: 1 . Detention - Release 50% of 2-year pre-development ' Detention 2-year post-development - Release 25-year pre-development , Detention 25-year post-development 2 . Water Quality - Biofilter swales - 2-year storm ' - Velocity less than 1 . 5 fps - Flow depth less than .4 inches - Slope average 2% to 4%* , - Min. length 200 ft. - Side slopes 3H: 1V or less *Due to the flatness of the terrain, this criteria cannot be ' met . The swales with the slope less than 2% are designed as wetlands with riparian plantings . For sample Hydraulic Project Application Form, see Appendix. ' Other Permits ' SEPA Department of Ecology Corps of Engineers City of Kent Pipe Alternates ' PH and resistivity tests were performed for this project and resulted in the following values : PH = 6 ' Resistivity = 5 , 000 to 30 , 000 ohm-cm This project is located in Corrosion Zone 2 . ' The information shown on the plans is based on using concrete pipe . Acceptable alternates for STORM SEWER PIPE are: , Galvanized Steel Storm Sewer Pipe: - Tr. 5 , . 064" thick. 35 ' Tr. 2 with welded or gasketed longitudinal seams, . 064" thick, diameter 3 inches larger than specified. Aluminized Steel Storm Sewer Pipe: - Tr. 5, . 064" thick. Plain with gasketed or welded and remetalized longitudinal seams, . 064" thick, diameter 3 inches larger than specified. ' Aluminum Storm Sewer Pipe: Tr. 5, . 060" thick. ' - Plain with gasketed longitudinal seams, . 060" thick, diameter 3 inches larger than specified. ' Spiral Rib Storm Sewer Pipe: - Plain aluminum or plain narrow pitch aluminum, . 060" thick. - Plain aluminized steel or plain narrow pitch aluminized ' steel, . 064" thick. - Tr. 2 galvanized steel or Tr. 2 narrow pitch galvanized steel, . 064" thick. For CULVERT SCHEDULE PIPE ( Standard Plan B-17 ) , the following note should be added to the structure note sheet : - Galvanized Steel Alternate shall have Treatment 2 . Acceptable alternates for DRAIN AND UNDERDRAIN PIPE are listed in 1 the standard specifications . No treatment is required and no additional notes are necessary on the structure note sheets . 4 . 5 Section 3 General As SR 167 crosses over 84th Avenue South it becomes again a freeway with low embankment for most of its length. From this point up to South 180th Street the freeway drainage conditions are much like in Section 1 except the ditches and ' channels along the embankment are better defined and off- site and on-site runoff are separated. ' Between South 180th Street and SR 405 the freeway serves as a dam for Panther Creek Wetland. The situation and proposed solutions for this area are described in an engineering ' report by R. W. Beck and Assoc . called P-9 Channel Design. For our purpose suffice to say that the City of Renton officials in charge of storm water drainage concluded that: ' a. No restraint in flow from freeway to the wetlands (like Panther Creek Wetland) is required. ' 36 b. Elimination of the numerous pipe crossings from the ' wetlands under the freeway to the west side and usage of one controlled outlet is desirable (proposed P-9 Channel crossing) ' Streams . Due to the size and complexity of drainage basins tributary , to each creek, design flows for creek culverts were not calculated. The impact of SR 167 widening on Springbrook ' Creek, Garrison Creek and the creek without a name within the City of Kent will be mitigated by releasing 10-year storm pre-development flow from the project while detaining , 25-year storm postdevelopment flow. Within the City of Renton the mitigation will be done by releasing 2-year storm predevelopment flow while detaining 10-year storm postdevelopment flow. , Flood Plain In Section 3 this project will affect the Springbrook Creek ' flood plain since some of the proposed berms will encroach into flood areas . Since this happens only intermittently, it will be best to see the drainage plans for specific ' locations . The widening of the following ramp will also encroach into the existing flood areas : S . 212th Street Interchange EW-S Ramp Springbrook Flood Plain Channel Changes There are no channels located in Section 3 of this project. Culverts A 42-inch diameter culvert is proposed to be added to provide larger capacity at Springbrook Creek crossing of SR167 . The design data for this culvert were provided by the City of Renton. The City of Renton also proposes a single outlet out of ' Panther Creek Wetland. R. W. Beck and Assoc. has completed Panther Creek Wetland/P-9 Channel Design Draft Interim Preliminary Engineering Report which is part of the Eastside Green River Watershed Plan. Further work on this report has been discontinued. As can be seen from the correspondence with the City of Renton enclosed in the Appendix, the ' original idea of the City was to provide details of the 37 ' SR167 culvert to be tied into the .proposed P-9 channel to ' WSDOT in time so this culvert could be installed as a part of the SR167 HOV Improvements while the City of Renton would make concessions to some of its requirements related to the detention of storm water. In other words WSDOT would build ' the culvert and the City of Renton would forego requirements for the detention. ' The letter from the City of Renton to CTS dated July 30, 1991 indicates that the City also meant for WSDOT to design this culvert . To-date there has been no agreement reached ' between the City of Renton and WSDOT on the subject of the Panther Creek Wetland culvert. The problem at Panther Creek Wetland can be summarized as follows : SR167 was built in the late 60' s and early 70' s and the Panther Creek Wetland was drained across the freeway by a series of culverts of different diameter. Each culvert ' drained into an open channel (ditch) running west from SR167 to Springbrook Creek. As the land use rapidly changed from agricultural to industrial, the land owners adjacent to SR167 started to fill in their lots obliterating most of the ' ditches and in turn causing a sediment to build up in the culverts which had nowhere to drain. Alpha Engineering Group survey crew inspected these culverts in December 1992 ' in order to provide up-to-date information about their condition. This information is presented here and also elsewhere in this report . Culvert I .E. In I .E . Out Condition Dia. ' SD 305 11 . 49 10 . 87 Plugged 12" SD 306 9 . 33 9 . 03 Plugged 36" SD 307 8 . 17 ? Plugged 30" SD 308 9 . 85 9 . 85 Clean 48" SD 309 ? 8 . 58 Submerged 48" ' SD 310 8 . 65 ? Plugged 36" SD 311 8 . 55 ? Clean 24" ' Looking at this information we can see that the Panther Creek Wetland is now practically being drained only by SD ' 308, SD 309 , and SD 311 . SD 308 is clean probably because it sits higher than others and SD 311 is in comparison with ' 38 others rather small . Out of these seven culverts only SD ' 309 has somewhat positive drainage due west via open channel OC46 as shown on" Sheet 45 . ' Open Channel OC46 runs west toward -East Valley Road where it enters grate inlet at el . 13 . 04 . Grate inlet is connected ' to 1 8" dia. conc . pipe which in turn is connected to 4 1 x2' box culvert crossing East Valley Road tied into closed pipe system built circa 1981 and running north to P-9 ditch (P-9 Channel is not built yet) . Inv. elevations of 18" dia. pipe , and box culvert are not known. In absence of an agreement between the City of Renton and , WSDOT, the City decided to add detention requirements to the part of the project within their jurisdiction. Several solutions for the Panther Creek Wetland drainage were ' considered and discarded. 1 . To construct a bridge or a large culvert at the proposed P-9 Channel location would be costly and it , would disrupt the traffic . 2 . To construct a channel along the west side of the SR ' 167 and intercept all of the existing culverts and simultaneously provide biofiltration and detention would result in a need for additional right-of-way due to large cross-section required. ' . 3 . To construct a closed pipe system intercepting all of the culverts and providing the detention would result ' in installation of a 8-foot diameter pipe for 4460 feet. The biofiltration swale could be then installed parallel to the SR 167 . The cost of the pipe system ' would be very high. These three solutions have one disadvantage and that is that the total flow is brought to a single point at the proposed ' P-9 Channel location and the only items in place from the proposed system are two 48-inch diameter pipes under East Valley Road. The remaining major part of the P-9 Channel ' must as yet be built. The three solutions would cause flooding between SR 167 and East Valley Road at the proposed P-9 Channel location. The one solution proposed as an interim solution and also ' presented in this Hydraulic Report involves capping off SD 305 , SD 306, SD 307 , SD 308, SD 310 and SD 311 . These , culverts with exception of SD 308 and SD 311 are plugged with sediments and debris and do not presently work anyway. SD 309 will be cleaned and the open channel OC46 with the inlet at the East Valley Road will be improved. Ditch , 39 , 1 i i elevations of 12 . 0 shown on Sheet 45 are based on assumption that OC46, grate inlet and 18" dia. pipe will be revised below el . 12 . 0 and thus improve drainage west of SR 167 . To compensate for the plugged culverts, we propose installation i of two 48" diameter culverts crossing SR 167 at the future P-9 Channel location. These two culverts may be retained or replaced with the final P-9 Channel structure crossing under i SR 167 in the future . The summary of remaining culverts in Section 3 is as follows . The culverts carrying flow of Garrison Creek and a i creek without name ( "No Name Creek" ) across SR 167 will remain unchanged. There are no proposed interchange or private road culverts . The following culverts will remain i as outfalls : SD 265, SD 267, SD 269, SD 329, SD 275, SD 278, SD 279 , SD 282 , SD 381 , SD 294, SD 297 , SD 302, SD 303, SD 309, SD 511 and SD 513 . i The following culverts will be intercepted by the proposed biofiltration ditches : SD271 , SD280, SD281 , SD283, SD284, SD285, SD287 , SD289, SD291 , SD292 , SD293 and SD347 . i The followingculverts serving as outlets from Panther Creek g Wetland will be abandoned: SD305, SD306, SD307, SD308, iSD310, SD311 , and SD410 . iCulvert End Sections The following end sections are proposed for the new culvert icarrying Springbrook Creek under SR 167 : Upstream End Standard Plan B-9 Concrete Headwall iDownstream End Standard Plan B-9 Headwall The culverts proposed for a new outfall from Panther Creek i Wetland will have the standard concrete headwall at each end. iDitches The ditches in Section 3 can be divided into the following icategories : a. Ditches with slopes 2% : 1 1 i 40 . 1 . i For the first 200 L.F. from an outlet or a flow control i structure the ditch is sized for biofiltration or detention whichever controls . The remaining length is sized for convence and velocity. b. Ditches with slopes < 2% : i For the first 200 L .' from an outlet or a flow control structure the ditch is sized for biofiltration as a i wetland or detention whichever controls . The remaining length is sized for conveyance and velocity. The entire length of the ditch needs to be seeded with ' riparian plantings . Open ditches will be used extensively in Section 3 of this project either as an improvement to the existing Special i Ditch A or as a new installation to provide biofiltration treatment . Light loose or heavy loose rip-rap or quarry spalls are i proposed at points where pipes or culverts tie into the ditches to prevent erosion. At several locations it will be necessary to provide earth berms to keep the runoff within the right-of-way . For information related to the width at the top of the berms to ' facilitate access for maintenance crews see Sheet 63 . Enclosed Drainage Enclosed drainage is proposed at the following locations : i Sheet 30 & 31 DR1 Sta. 893+45 RT to Sta. 902+00 RT i Sheet 31 L Sta. 901 +00 RT to L Sta. 904+00 RT Sheet 42 L Sta. 1050+10 LT to AL2 Sta. 56+75 LT Sheet 43 AL2 Sta. 64+50 LT to AL2 Sta. 66+00 LT i Sheet 43 DR2 Sta. 66+00 RT to L Sta. 1073+00 RT Sheet 48 EE Sta. 988+55 LT to EE Sta. 990+00 LT Sheet 48 & 49 AR2 Sta. 86+70 RT, AR2 Sta. 79+90 RT There are no storm or sanitary sewers belonging to other i jurisdictions which will be affected by this project. Gutter Design i Concrete curb and gutter will not be used in Section 3 of this project. Asphalt curb will be required to control ' erosion at the following locations : Sheet 30 & 31 DR 1 Sta. 889+00 RT to L Sta. 904+00 RT ' Sheet 34 EW-S Sta. 41 +45 LT to EW-S Sta. 49+00 LT Sheet 35 WE-N Sta. 39+00 RT to WE-N Sta. 47+00 RT 1 1 41 Sheet 42 AL2 Sta. 51 +50 LT to AL2 Sta. 56+60 LT ' Sheet 43 DR 2 Sta. 66+00 RT to L Sta. 1073+00 RT Sheet 48 EE Sta. 988+55 LT to AR 2 Sta. 78+00 LT ' Asphalt curb will be served by Type 1 catch basins and 12- inch diameter pipe . Detention ' Detention in Section 3 inside the City of Kent limits will be provided by detaining water in biofiltration swales or ' detention pipes using 25-year post-development storm flow with 10-year storm pre-development release. Within the City of Renton the detention means will be biofiltration swales, detention vaults or detention pipes using 10-year storm ' postdevelopment flow with 2-year storm predevelopment flow release. The flow control structures (FCS) are proposed at the following locations : ' Sta. 909+10 LT Sta. 916+00 LT Sta. 935+15 LT ' Sta. 960+00 RT Sta. 968+90 LT Sta. 969+10 LT ' Sta. 974+50 LT Sta. 974+70 LT Sta. 993+90 LT ' Sta. 997+15 LT Sta. 1000+40 LT Sta. 1017+85 LT Sta. 1018+15 LT ' Sta. 1029+85 LT Sta. 1041 +55 LT Sta. 1041 +85 LT Sta. 1049+75 LT AL2 56+75 LT Sta. 1064+50 RT Sta. 1071 +00 LT ' Sta. 1101 +50 LT Sta. 1102+50 LT Sta. 1120+60 LT ' Sta. 1121 +40 LT No retention ponds are proposed for Section 3 . ' Due to the lack of space to construct detention facilities along the east side of SR 167 and due to the large tributary areas off the project site draining to this side we have not detained any runoff generated east of the SR 167 centerline. 42 To compensate for the undetained runoff from increased impervious surface of northbound lanes, we propose to limit , the flow from the southbound lanes so that the total runoff equals the pre-development stage. To do so will require large detention volumes to be provided in the ditches along the southbound lanes . , Normally this would be accomplished by calculating pre- development 10-year storm runoff at outfall locations and ' then providing such detention volume for southbound lanes generated runoff for post-development 25-year storm as to result in the same flow at the outfall as for pre-developed conditions . t To expedite our calculations we looked at the possibility of calculating the detention necessary to limit the runoff from ' the west part of the SR 167 to the flow from pre-development conditions for 2-year storm. In order to prove that this approach is valid we have chosen ' a specific area for which we have calculated required detention volume based on the normal approach to detain flow from post-development impervious surface for both northbound ' and southbound lanes . This specific area is on Sheet 40 and the outfall is SD291 . Then we calculated detention volume needed to limit flow from the southbound lanes only to 2- year storm pre-development runoff as a shortcut method. The ' shortcut method has given us larger detention volumes and therefore we used it to size the ditches along the southbound lanes of SR 167 in the City of Kent limits of , Section 3 . The above mentioned calculation follow this page. 1 43 if it VI if 1! 0 ;J -1 If I-J Q if A Lij 1 cn ,ij it r3i Ga • > If IIJ if N F 1i t7t, it 77 CU if al *1.T It it 'Ib H Ql AP TH it Lo J.. It t I Iwo m m _. Ii { i I i ! � � •1 i !s Lu ! =1 :ri rii A F-+ C, I u !! at it C's' II 3j. r� ..� r �. i j i7 i L.J _—j f S. !! �n U.t a, r •r-i � '�'1 i•-I 1! 1.11 }— Ii 14 j ! i.lj _Iu i ! + ! 11 H +�a Qj dt i f1 11 !.f1 i ii Ll.l ii 0.1 1_.:I I! 1`t ' rll i 11 ll ! ,•�i ' - N� 12/16/91 CTS Engineers, lncoruora ed COMPARISION -- NQIZMA~L hSTHOD ===================================================================== N� BA, U.MX,ARY N� BASIN ID: A1 ;N" P;1 PR� 1� yE�AR ST3�� SCS METHODOLOBY TOTALAcres BASEFLGWS: 0. 00 c�s RAINFALL TYPE. ' . . : TY PE;"I'Vi.OU R�A �RECIPZTATION. . . . : 2. 95 inches TlME �F CO�C. . . . . : 8. 00 min l)�PERVI��S A�E� �� A�STRACTION COEF� : 0. 20 A�EA. . : O. 58 �cr�s — BASIN lD: AR ST !NM SCS M�T�O�OLO8Y -- N� TOT�L AREA. . . . . . . : �. 64 Acres BASE�L��S: C. 0� �ps =~ RAIKFPILL TYPElA PREC� PITATIO�. . . . : 3. 35 inc�es ARE�. . : 0. 8� �cres TI�E I�TERVA�. min IMPERVIOUS �REA ABSTRACTION A A. . : 0. 8� A�res N� PEAK RATE: 1. 0� cfs VOL: 0. 33 Ac-ft �IME: 480 min �-SIN ID : A5 NAME: A5 PRE 10 YEAR S �ORM N� SCS �ETr.ODOLOGY --' 64 �cres �ASE�LOWS: 0. 00 Cfs RP 'I FAL PE. . . . : TYPE1A �E�VIO�S AREA N� P��CIPITATION. . ' - : 2. 95 incIes A�EA. . : 1. 06 A�res 85. �0 TIME OF CONC. . . . . : 8. 0O min IN PEE RVIOUS AR A ABSTRACTIGN COEFF : 0. 20 AR EA. . : 0. 58 Acres C.N. . . . : 98. 00 OEAK �ATE: 0. 78 c f s VOL: 0. 26 480 min mm LA, 1,K 1.Lt T'. i IJ FJ A.. W ZI Lift 11 -:r -:v 4- it Oj !Ti aj Ii o Efj u3 u) W U') 6: 1 CK a s !L 0 R it _> t. I II f 171. (JE H e, 4N 0 fj ft it ij Q: 11 Cj LAI CO C33 0 1'41 11 f! II G-j fi-j f-I r� 10 11-3 l It-) -T -.7- CL Z:. X C1 iD I.- 0 U.] (Z fil I'D i:T 0.1 11.) L* j 3 (X lfl a 1A I I !TJ ff., t-.I IT.I �3.,. JO i-ILI if U) i ri ii ti ri Ej 11 I J: - It ua C1 IVI Ir if if CX �X. -1 LJA if L, v, Q-' al I H I11 p is -Ij if -3t it 9 nr, 111 it Uri It Ira sT; if L ID R if J 0 if 1 0-, u 0 :-1 11 : if it LJ s i j o'3 -D T !171 ill C> i3l in frj tn u J Q! 0 -D j, Cl 1.1 A Or 10 LL rn W . R. Nj ii Z uj Z 10 i"T. 1A K z'.f L.1 ;IQ rs IJ) @ IJ w c 2 0 H fn T k U if Ll cc A: OA ill -,,- 0. !.-j !1 tO 0 0 17T Lli 00 :'.1 kD U Ll CO., LI L L to Q) al _j H. Cc 1 f"j D hi In CC: al U, 1K H 1 U i w Ill ,W 03 is .-I !.-- i-- _j 1— (E ..) CF Cc CE n 0 Cc M, �-f ft on izf !'J� 1j) OL i i J LL In ­! CIL U Ll 1 11.1 u J L u A., , * " 3.- D 1 - �.O L:L CIO M 1 it! f."; 1: !-1 i-n QL Lj Qj c! Ur on fQ 111 ' Q G L!- W 1,j cc 1:... F_ V M EL IT4 L ki) i li ii J ali Ll (T. "Z 0.1 h7l !tl LJ CA ill AP :3 (0 I L Ld it 4 7 C V N 1-3 it: L'i 0 rl. L u it ,.z- GO 11 LN it '! "i *D t" .0 U r7p it :aCE J) > LA fl) th it L > cfEl . . . . !it —Z— C 11_ T I LI —1 T I.,d CI I'l j LT 1j, I*J — I)J I'D it (7L J j: 1 J :L .-A it -.1 IL i.rj (.0 1 10 Y. LO !aki (j) uO i;.,! .3 if ill U-1 t�T i:T !.f.. ' 12/16/91 CTS Engineers, Incorocra'�;eu SR167/ C���ARISION HYDROG�APH SUHMARY �� PEAK TI�E VOLU�E �iYD RUNOFF OF OF Contri � N� �U� RATE PEAK �YD�O Arsa �� cfs �in. t �cres ============================================= 1 0' 778 480 11353 2 0. 778 21 �. 013 480 �45�4 cf 1. 64 5 1. 557 480 22707 cf 3' 2� 6 0. 378 480 7 0' 445 500 B42�� cf l. 50 �0 0. 445 530 1451� 11 0. 37�� 550 145 cf 1. 64 Descrintion: DITCH m� Length : tvioth : 4. 00 ft. Sice Slope 1 : 2 Si-2e Side Slooe 2� 2 Side Slooe 4: 2�0 ~� Infiltration Rate: 0. 60 min/inch DI 6� Descriotion: ORFICE ~� Outlet Elev: 99. 90 Elev: 97. 90 ft [}rifice Dia If,et 6 LEVEL P0OL TAE�LE SUMMARY MATCH INFLN -6TO- �,'.TS- <-P=A�- S�6�AG� �- <-------- (chs) (cfs) --id- --id- (-STASD id VGL (cf) 25 Y] STORH�2 �� .........,.. V.3� �.01 \ O\ 1O1.54 1\ �677.23 � � \�� \~? ��l ' Subsurface Drainage No subsurface drainage is proposed as being added to the ' existing one in Section 3 . For more information, see Soils Report. Existing Utilities There are numerous existing utilities crossing SR 167 in Section 3, but we are not aware at this moment that any of them will interfere with the proposed drainage . Water Quality ' A water quality assessment has not been done for this project . The intent is to install biofiltration swales almost through the entire Section 3 along the west side of ' SR 167 . The length of the biofiltration swales was limited to 200 linear feet minimum to reduce the cost of the project . The biofiltration swales with the slopes less than 2% were designed as wetlands with riparian vegetation. The ' 'PS & E drainage plans need to coordinate the installation of this vegetation with the landscaping plans . ' The proximity of steep slopes next to the northbound lanes along the east side of SR 167 precludes construction of biofiltration swales . ' Fish and Wildlife Requirements The requirements of the Department of Fisheries Hydraulic ' Project Approval permit are: 1 . Detention - Release 50% of 2-year pre-development Detention 2-year post-development - Release 25-year pre-development Detention 25-year post-development 2 . Water Quality - Biofilter swales 2-year storm ' Velocity less than 1 . 5 fps Flow depth less than 4 inches Slope average 2% to 4%* ' Min. length 200 ft . Side slopes 3H : 1V or less *Due to the flatness of the terrain, this criteria cannot be ' met . The swales with the slope less than 2% are designed as wetlands with riparian plantings . 52 For sample Hydraulic Project Application Form, see Appendix. Other Permits SEPA , Department of Ecology Corps of Engineers City of Kent City of Renton ' Pipe Alternates PH and resistivity tests were performed for this project and , resulted in the following values : PH = 6 ' Resistivity = 5 , 000 to 30, 000 ohm-cm This project is located in Corrosion Zone 2 . ' The information shown on the plans is based on using concrete pipe. Acceptable alternates for STORM SEWER PIPE are: ' Galvanized Steel Storm Sewer Pipe : - Tr. 5, . 064" thick. - Tr. 2 with welded or gasketed longitudinal seams, . 064" ' thick diameter 3 inches larger than specified. Aluminized Steel Storm Sewer Pipe: , - Tr. 5 , . 064" thick - Plain with gasketed or welded and remetalized longitudinal seams, . 064" thick, diameter 3 inches larger than specified. ' Aluminum Storm Sewer Pipe: - Tr. 5, . 060" thick. - Plain with gasketed longitudinal seams, . 060" thick, diameter 3 inches larger than specified. Spiral Rib Storm Sewer Pipe : ' - Plain aluminum or plain narrow pitch aluminum, . 060" thick. - Plain aluminized steel or plain narrow pitch aluminized ' steel, . 064" thick. - Tr. 2 galvanized steel or Tr. 2 narrow pitch galvanized steel, . 064" thick. ' For CULVERT SCHEDULE PIPE (Standard Plan B-17 ) , the following note should be added to the structure note sheet: , 53 ' ' - Galvanized 'Steel Alternate shall have Treatment 2 . ' Acceptable alternates for DRAIN AND UNDERDRAIN PIPE are listed. in the standard specifications . 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' A. , t �� t t f.: i lta �' y a 1"1 i>-kiz �` '� 4 b s+ an P + 'f=��'�- t `�" 2y "r'�"•v n'r z "',7tt`�'a - r^,J a a a ..,,, a K ���"t z'+ wa•` is ,Ne1^ as .��'d '�, � T§t;` x, % et .a ,- z .-11 �2 •Y*Y,.IL s y y- ,,y x,�,11 ed,, >.r ,# t r y/P� n 4'r ,i-.,s e, I k 2W a.7 ..+ ll� {, .'6 1'i)Z 'sT.�9 d'`L-• {4 i y ,� ,, �{1 � v j jr k � ��a}d F +r t '+ F.rr`` F, 1.i r +"; 'ate, b !1'A �y}4rt.'(Ht „lg� 4+., _.F R �' 1` .^TWp`•!r" H JSy t F, '1'4 kqh RM4"Y',;M . F`ro�' "Ik' 5i..""^( '%a d^• 4 �i ` 9t 5 ►,t ,^t»t5 w �r ht w Y + . '1y': t,s, , -tat x x t-r s r f �, r "`t r P. fl 's-- < , 1 } _ _ § ' % 1. tr t F- 1 ' 5 . 0 DRAINAGE BASINS The proposed widening of SR167 is within nine drainage basins with the Rolling Hills Creek ' Basin added for completeness as this basin contributes to the Panther Creek Wetlands . The complete list of drainage basins is as follows : ' BASIN 1 - Upper Mill Creek (Auburn) BASIN 2 - Peasley Canyon Tributary to Mill Creek ' BASIN 3 - Lower Mill Creek (Auburn) BASIN 4 - Green River BASIN 5 .Kill Creek (Kent) BASIN 6 - No Name Tributary to Springbrook Creek ' BASIN 7 - Garrison Creek BASIN 8 - Panther Creek BASIN 9 - Rolling Hills Creek ' BASIN 10 - Springbrook Creek All effort was made to provide biofiltration, detention, and flow control structures before any runoff is released into ' the creeks shown. Only very few areas were allowed to drain directly into the creeks effected by this project. All the creeks are tributaries to Green River. USGS maps which are ' used to delineate the drainage basins, show Mill Creek (Auburn) as originating in Lake Dolloff. FEMA maps show this stream to be only a tributary to Mill Creek with actual ' origin around Algona. Therefore, we decided to designate Upper Mill Creek as a separate area. 56 o7 m7 m) m 1 • ow mm "3 ow ow OR ow w P" Omni ii UNITED STATES POVERTY BAY QUADRANGLE DEPARTMENT OF THE INTERIOR WASHINOTON ;°�` GEOLOGICAL SURVEY 17•t 122-22.2a• •1r-1 'I WIND«n nouTro •» 20 MI Nlin:o,wts, •.[ au.n.r.rr r mow, 7.San MINUTE SERIES(TO/P06RAPHIC� �•• - •'O'••++ 91 Ir30' taooDD I[[t 122'IF' • a il•'•. �L a•Sel �� ,� t 21 e I Y_enE. 'i " • 2770' 2317. )_ J LN•M12 / -. I.' �'� '�� tif.�-•\ �' 3 awlk ---= M., , CP Woodmont Barl'i 'r'" r It � r� i 1, I �'.,t •f S j irL / ;p }�J//�\1... \ 1 ` :rS;�i II { Ir,l1 • POVERTY BAY �r �' ( ( ,_ l � � --. _ �►"��..35 A7T ^\ V * ••+•�• ,^. •�.Jf\� n ,11;'��, Iwaao FEE' Iswrl.i •�`a: f 11� -t• •� .r �l 1. 'I�L IiroRi«I •Li3 �f 4, \ ./ I�. .. r y` i 8 "1h 1• �• 2 122M � L ry� l!11 � ( ���1 •3�. ?! l `! _�,�....II,,.._-ii��.....--++*+cam.':� -G" ` 1..1�`•twt �— �__ ��;; `` � � I �.c \�� '� �/ � �l' .m r � .,ice_ � •.� 1�'.`.� / ..t, ��Ia 1 1� � •/p,L.';,'a:+F f� \.\��' �� ` � ��L.r �Sf�l "� _ ` r V�ib' %tl }� P . i� � ` 1' ,. 1 \l it ,S i_•aL r,, :1 � 'j��� l�p'.1! a yr /i •f''h.' r '"� #F� `-11 •` //IIIn - F 2, `� 20 IPS'r� t' ,,, � ' 'Z:L�r• yE ItA� 'y"^«ql :�' l �'I ,.��+c�'i �. ,y• •` � �`:ry `J1- a� /Cr///l R/ - 1 `f 1Z .� 't•F� _ �i.,,. Y+r�A� '�• � ; .. I >ti O,( �'E NF�I'4� .1 � � �. 'r A.i�`� N••y}•I( -� E r�.�1 � ..il\iC3'����' �J,. ""M�i )' •r .$ ,i RF` �, � /' I :ra'h l _•.aC ' r`+L,MrI L f �:' �• i`.nt# ['I, 6 r- ,r. �, c� R L (LAY , t�l�•'1.�' _ �•EI �� :Iwl )1,1J/��_S ? Ju.�� i'9 H.Iwr 1 �F 'i'r:..l `e. }•S�` _'.'ti' .��]/�� !"( 7• _f �( '• _t' �j, ` 2r .`l\.: \ ""'•'E 1 _S - 2N Y 1. /..✓1-y �! �r5. • w \_/ •11 1.. 1 v 11'�^ 7. I 'i, 4 yij IMPI ��'��7Y !i-•..���•• ��j• � � f � `I1�� - � �( i 'Si �it �., ��, •(a \''.�.-1 � ` � �./ �' Va yjf.. 1 ,C ` 4.. _ r _ Q f ' a'.•�' ••'1 C • Slf�el i •m 1�'.i��'• _ /F' t '�..:� 1 { J� _/I„\',j�- i�_�A(• g �JV1.-T/r- J I y:.l `. :� ?fy Ni;. \VU/// I. l.o -7i iF• -�\:� - '+Kls J e• �_Y�"r' } 1 FA'--1 ____ ' �titS. vn.w •.__�. - 1 �'.�°�. ? �. �I A IHP ��._ ��' 1 � �. . �+ .:f � .jam a �'. 'i° •t .•�:_: tr. nil ` ��,,`��� `�v' �a� ° 1 , '7 � BEGIN PROJECT.AS.P.13.73 k (: •.`"-( T I \ i BEGIN HYDRAULIC REPORT \ /) /I-) J /'r ✓_ SECnONI � :.T ^ 'O� C J ]rw 49 ) i�.•,��>��A'`,� { �' �T�•\ 7 i (�' i � .l`r � ,•!'. p a is d I MIT A ,.• an 7. n ,5�1`^ll i - �••' i r .:s- '1:j`'(v r' � 1 e E •'q�':�o ._ - - .a,,�:'q•.h:,': �fol'`�.•$,.e�T corn , � I �' .S`: �/ � 1 r_ •. ,. �' „t .. ._mot •• �(`L I '• rl%I ' ).a1 r ( '�'A ,• ' 1�.t`� Al -si.. / Io•=FEEr •e �. t II t}<--2� tu- r - ,.31t r.:• �..+Y} - I IMORT«I •�� �: 1l,i�, ) I' !( I L'' •�:1 ..,t•.. �.1! � .� �_�[ L�3 91. .� I � � 1• w • !I a Pacific _ rN v \ I,• T.SIM - .- ( � _i'S ' t � \`�I 1t;`-,'+-' o" :L y _ y._F � 1 r ��-1 1 ` rn �•-a T.20N S.•M.N�. nL II 'P 9 :I!h. ) 1 s' r". ~• 1•' • 1 •rn r w« - .. 1 `„•I.e�'. ► � _i �I _ .5�1$ r. 7 iJ a. U 'ir1 '��+ 7+ Z'••ti.T'- -�\.. 1,,, .rk t. ...r 122IS..22'30• I..—ICE, R.3E a rL Ir„M � r-urAuurl J•.•: •••L`I I - . CR,«i p•(reC • „r,,,,« •sl 17.30- 11[0oo0 IE[I•. s ar, M.PW.eortea.area oubb Mea D7 the GeolotiCll Salve) ,NV•raarw.+•" t110Y,«I • '1TE _' 122•IS SCALE I:2�OOD aMrra•a.r. � J fa.�vl p VSGS Fna NOyNOaA 5°� IaF,Vra,n••.alNl w • ' ROAD ClA551fIGIRIN •�;: 1 o Ir gmrnw..M«Mm NMn.,. 0��.`• el••«t•Fr•,wen 1 59 1. f.Y cl•«ua 1%I Imo• o I® � � •® +® ,� +wo«n 1r •' 4,.' SM•L W NpgrMM aaU,•MpI•a NMn NOS tN«, � / IIaa+YduM1 y+a•, ... 11 ,.• 4W)•n0 Mb0 1191U. iM wrs�n«s w n«•nr•m•a Nr I 1 naP[in 0Y _ , u a1L'DIINIIOYII U1,9IIDrPea C�-.... hNm,N orwc nrM'ID.000b«Era I—wve r r•.bMs ,�' Iw CONTOUR INTERVAL 20 FEET )IIIINSIyE Rrb ~'U S RW, �Stata R.- •,Mwn.Mn w vuln rr.,. IOUOMw M,SNVD,W "• - winrvl Ir•nvvry r,NaIM pM I<\,,.w 10. DORCo LINES aE IS S to.1 1XOF 11. Mwn•n b 1^�7)Nmn.m.run p«vn. le s,Y.w Ilr, NaigNaL O[ODCIK YERIIGLI uI UY Or 1939 r.n DM,M I993„o.Ine an«euases AN.souMON•Os n1 r[n-aarlwl IS rur LorrtR Ear SISTER 'yo'••[n�nrML 73 mrim mnn FM 93•Niwn uM IIIDNI a,lNn./ND« Iw a�i va«aL YIr Goa rp 1Y1 MrN1f rllp",Ipl N aarN«, 11LI+'(ll1 NrW Yale ,SooM.nn«. ouw..«cLE 1Du.nN POVERTY BAY.WASH. F_«e m«r I••e.nanMa vMLIw I•rNF I•^^ ?HIS MAP COMILICS 111.NATIONAL MAP ACCURALY STAN"MOS rM715­12215/7.5 r,r N"'MiIIwYI—w.• 'u..."Ei•s'I""Mw.wl�""ainN Ma FOR SALE By U.S.GEOLOGIGL SURVEY.DENVER.COLOW0010225,OR IIFSTOM.YMGREM 2M92 EMI A rauR Dlx•bnrO roral:w.«a:rus ANO 1•M—a IS A9A c ON moms, _ 1a«vavan.TM....•':`p•i�x oira..:.�".n..,. - ,« .. rr nn,.... ..-,,.... OYA t•ta wrl.r I•n�.rM cN... ,.en,r wa „- y V' "t UNITED STATES UNITED STATES AUBURN OUADRANGLE DEPARTMENT OF THE INTERIOR. DEPARTMENT OF THE ARMY WASHINGTON a • GEOLOGICAL SURVEY _ CORPS OF ENGINEERS - 7.5 MINUTE SERIES(TOPOGRAPHIC) at A n[ -W-1 129EI" •M Iw ILI Ar Ip'`I smco�rcr r»DAL• Aµ ALI 17Y07?^' END HYDRAULIC Jw �2a_hent _!� . 19 �� • ?QI- u, 20 :-` 1;• .. Zz. � LIC REPORT —ar- '• ti•: SECTION 1 -T� 1`` • `' •E!n w. : t i' tt1`e`=I i t r.BEGIN HYDRAULIC REPORT --- --_Y- ` �_— • ) :,- T^ 1 '�1r," !� °r..'E 6'� L• '- END CITY OF KENT a� I:•+e.;•• pel T .. t\ ' \.. �� -�� "•,SECTION ; \•�r $�$ •ti• t. .:�- r- ' "T- ` -� ; ZONE 1 .5. 2 BEG N CITY OF ND. w 3� i1 ��:` \'•"`::� c `i oa I 2 (' w9�N l t I i••ZONE ila I ,- \; ^� a- T eE • \v� 25 -• `'• i t N• 529•7. ':ir� .•�- u.., ``•• — Y. \ � 1�. �26 ; _ iwe 39 ZONE I CITYTX BEGIN OF KENT , � \\` v� h \'` `? \ _• -1 }}- aJJJ' a\ Thorruu• .., \�, In�r f , �'= I i..�1'• �• u �L.! u •7.7.36x 1. .'s I .3; ° r�1 ' `� /^ , .,.. _ 1."•-_ `=T; A 1.00D)IEC T.Id� C IA 1 (soul-, E.� - ��. _` ! �I\. *' .\ 1 - ' �•' IN o0o rcr Al $.4e TH ST. ;Y �� l tMenv'dNk'1• � i.xx N. T.xl57 M. _ �.\. L� _� ••r.•.•• I ` _ __1 ���}�� 'bi i- N......•.....• <Ci-� '} Y 1,('`\ TL. I� �• r) a nl\ �. t i M7 t � Z m .. ' 1camr 'all._ _ V. �• �Tt j ` t I p?1, a -g westmaro... •' •'••• rv1, \ JI �1 � N�7y� : 11(T11 �sT���l" I,r,�= '�. 11= 4 ''-�•,� I.� I 1 'MF \ 1 , 1� �i . vY.y`� C7YOFAVB � -ICILY0FAI.G G ;I. tg /.r• 'j � ,2 M. aar 7:T f 25�1�.L_ 30 _D•S ,y»• r../tea r: ..�• I.r .y8. =.`�' 27 Algona •I `rG•tt•� •n\ i I��• ,- lA 13.m FEE, 1MCAT \,r-' :`'... :•Pacific 35 •36 ,� ` - ' ^; . i,A:. •• JAI I t.xl�i'I 'l.• /_`�^ I. li ' Ic ` t- �• 1 ��((\pp••-l��'�1� ,x� -• q/ •:escr--::En INw..: A.1 Ipr:�..- +f9 173f!' 'u au��a„I 16 1p I Em000«nlsoulNl� , _.'. ....-. ._.�.. t,•'• 1L. rJ ,, i--•• wrE luror3o= Mao CTC rr In••A My Mao Service SGIE 1.24OW r 1»�u ROAD CLASSIpiGTroN f•UDUsne:m•CN,•LIM Dq'the Geodopica:Survt. +i. Inuw•uN_ LipMoutT_ (.OnIMl e.US:AGS I1Io r.mp CDunlr Enpmev OIICr Iprn a ImL lac Imr 'or fmi m +om.a+ teoonlrwv rn n.enn om- ' ""^<Un Unm,p�aw air,.._..•_ oprlOnf 0y Mu 19 MtMM Awu�ono14 IDn;la.en 19J: E,n0 cnK.19s5 �' / ••'—•� _....I... ..-e r I AaoeMl. ,� Cj Wit Rant p—mv orm.— 1927 Norh AW;M oa:ur 1 I Ipc:nn•P Lf D,fe ..wain CONTOUR)N(RVAI 2s pie• Mp10n soranl.M fHlt!. MATgNAI GEODETIC WWO DATUM Or 1929AUSURN IID,In Ir:fCJln SYIt: / »rrr- a»n.a vwr- a11oAa+:u t9ulloA ASH. unoml,.cu:�np;Ire fmiwr I...-CO.11IES MIT„LA 10..t...ACCUNACT Sla'".DS Na715-WI::G7.5l7.: FOR SALE SY U S.GEOLOGICAL SURVEY.DELAYER.COLORADO 50225 ON K57011 VINGINIA 22022 Nn Mfnr7irp^rf MiDt 0lllrefrl o:.MMnp:,DIM: A IDIDIN DES.RI IO'OGNA`"`C MAeS.ND SwROLS N-AA,(ON Atoms, 1949 LDMMlrCM In:M0:1fnY1 Gnem�: MOTOR[VISED 1965 AND 1973 NET a•nn _:..- -Iw•v arnr,«•vrrrr•-•n .. AMS IS«1 SW-SERIES Yql Unenee.lo fM'a00nf Jn frlDrn M Orpn. e1..[ere••11•r-'e90e••1'�?"Tn�.�••n•n•pt••w wnr,n�L K.•. D.-yn2+rMf-At.IOp01,mA1!Ip;l:iMl! y p•r nnl�nt..plll•.le.i.. ...... IOODreKer U-1 TlanSVKTt MRMMM Eno m.S ` iont IC.fnn.rr rn pw W old 1 711 �' �^�i� . ,� 22 /W � t guile IVA AA Wgcjl IN son . MITI fjlo 19 ,, �� Narmandv Park at NOME- 1Cai, �� Its „j % Fill MAURY ISLAND f � � UNITED STATES UNITED STATES RENTON QUADRANGLE „t'l DEPARTMENT OF THE INTERIOR DEPARTMENT OF THE ARMY WASHINOTON—KING CO. GEOLOGICAL SURVEY CORPS OF ENOINEERS TS MINUTE SERIES(TOPOORAPHICI 122.15' •57�•[ .•1^ ,A,a 10, y y m I axlRp rtn 122'0770" 17.3p' R.[ a S( e.. .Y770• ry r••Aera. _ .. a 30 us 'IP�B 1-- .•:� II y arlPo , _ ,�.:, ,' t- 1 ,I _ � ��_�::�- q0 i I •� q r .ram:.IONlaom •w °•1. •..- .�1 . 'to ;°a -91w �o _ •� ?-1i a•; '� lr.�� .j- L .... -; :'.,l alb - .>, I r`.--.,___ '18 R - :� � .. sue,-°s 1�°�y c r r• O' :. ''}fir' i (3�!•• ' - .. ll�aak { i _ �. ti. I � � � 1 - - �•:••� _� fit. •f;.. END PROJECT A1.P.26.37 --- -- -- — --*-'--••�•• _ — _ --- END HYDRAULIC REPORTSECnONJ r?�l�. ¢1• 1 �• n2►• ' ` f ' 3-1 11 a � { x;FIT '_+..w.--1 I. �'•.\' ��/'ti c..�~.� 1'�- ��•�,/��- _ mow•__^r��— �[,, � - {. 27'30".. i t n -11 II : 'A m a t ( l I .x D•3B" B I F EDNE CITY OF KENT ---8/"` -y II �'t _• `�/ `Y- 1 Z M"S3J'- F KENT T.22 N. -- IV �r19}'lia _/ r` w •w '."' r.a>t k. 1 •T � i ~�- M/' J - e , .� �ti r - r 1 � x y BED ` ° 1 1: .,S w \ I r to •i�•. i 1 t t �., r , I Ua L / r• tt 1,• I, 4-, s •i ' .•nc 7� "'l _ a — .F ''.i) � �' `yr � 'ii t T,y � _ 'f.r�a rj• END HYDRAULIC REPORT !S �.' s. �,•SECTION 2 'r - 12 1 BEGIN HYDRAULIC REPORT SECTION 3 • t' ISO ri 23 END CITY OF KENT i' �� u , ''': i 's t ••\` �, r ZONE 2 ��n �_ i !1 \1 •I�1 I `v\ (' wr•B BEGIN CITY OF KENT t ZONE 3Te LI. 4 .2D •; L� �` 1 � � 23 •.y 17.2 122•IS' a.'.,"nNa:s�(n ai.[. a.aE.� eR ava..aruw130^ y liiniww y��JJ 1a+ y. •....-..-..«�«'�'�..�...- •Ittro79o" .. Mapped by the Army Map Semce .u.ra.N.� SCALE 1:24000 pap ClASSWICATION 40 Published for ciml use by the Geological Survey , + ° I.0 '•,�o P�'�+ c9nbd W USGS.USC6G5,and USCE • ""'l'au'1 lolwgralHry Iron serul pnotgnapM M murodn metlpds +" +� ° !am 'm0 >® •® vm ram rm Milda odlh' Un«n°r°.ed dnt....... Aeru1 pfmlaaraphs laktn 19a1. [Mk Check 1915 n !AAo-stn Im••va!r�:��:: O SUte R.. P N,,—w0le t[on. 1927 Nanh Amermsn data 10.0001oot ark cased an Wadlvylon cowdmne system, I CONTOUR INTERVAL 25 FEET �'1••'G�0'• noun 1pN NATNIIIAL GEODETIC VERTU-WTUN OE IM Red ta!t kd-t.areas m-.h Dash a a o•w( rAlm, RENTON.WASH. IaMnwk bmklnp are slaNn ,,,.,,o,.,c1.lr.a s,en N47223-W i2207.5/7.5 N°dslrnctmn a made behI—d llmgs,bum. • 1NIs Nu CONKIE3.11.—.—NAr ACLU—T STANWAOS I:gnm[rnal ark I,dustrlal bwamg; FOR SALE BY U.S.GEOLOGtPa S EY.DENVER.COLORADO$0225.OR RESTON,YIRGINOI 22092 RMO,CIRkVISEn 1949ANy.In,, Unchecked ekratam are shown N CrR,n - a,IXIXa QLSCMIMC ipPOGRAPNa:wK ANO fwaOl2 4 AYAaANe Ow R[g1[Sl Aa6 IM 1 R9I_Fi1m m, Dashed 4nd Imes md-le app•eunale kcah°ras 4•rrv.r..•.....,m.nurn••rmm��IM w rase 1.emm�ul�u•...;«•-... 1000—ter Unrr 1 Tnm.e.se Mncata Pk ticks. •l..n.r n.lAs.+I e•:1^r> I-r.•,.,.•nanny«•.....n rw.!.. I•m 10.aMwn m due nu—,1,1�m.rar.e.»•, +«-.r..a... C) ' w PLO - o r R �Y 2Y 'fiY {tl 3 _ � s to � �.�> ��rr r��iF�� � �pv-'�• - � t {� p --� ✓ s� a:.as F at^,.�4 C'` �r�"4�T�t xi� I �F' tq :' S F � 7 t- '`y E.,.. reams, �:. { Ve } a S. � NB Ex/5t f'4Ve/77C/7f Pi'opO5Pd WidU7ing Pro/aoScc�Lonc —�roPG�Sed 5h/dr. s �mm�rica/ Aba11" � - tics / �xi5f ,UrC rl � �xisf Cafch $c5in 7-Y�1 CA L 7 of 6ECT/ON i- S7o: 3493 +OD 70 �to..3686 t Do 5oc/ CAtch 43,:7sir76 Will A/�o 1oc�.{tcd FIGURE A ,4t Mcdic�n NO ,Ex/5t Pc� rncr�7` 'ro �.c1 Wi&Cninq ��yyrr�rnc�ric�/ A. cff ffxce/oT For �roi/7oc�e Fw.St 5h/fir Srrucfiur�s /o' _-fir � lane f�o�sed ShJdr. 7y� 2. /�,t�ia/7 $arri�r 1�of/c C-�odc -1 �i5t tjrain Pi O mid or.<27k::� H9h 7 n Al 1$071 Cori TYP/CAI- SEGTION 5�4. 36B6 f oo -b .5ta. 3894 t oa ,�xisti/79 Catch csir/5 W/l/ 6c JC�mot�d. * won o7' 9;:-zr61175 or _Fast" amide of Median Wil/ 6,-- 0--cr nincd 5y FIGURE B 1�c�7dt1�acf -fcr-izonfq/ arzl Ve�'1`ica/ GZr�s. I =x%5t Pvvmwent Ito 5cd Wi riinq 5ym/r�fric / �lfao�f - 70' _ l2 1�of%G C-Vadc -- xi5f t7rain I'i cx wJ O n Eric/ or- �fch 5/n �' Gotch ,6--7--.117 At H&17 oink' (-6-.c Notc � ur-c 9) 5 7'yl='l CAL '6ECTION Sto. 38 94 t oo to �oc�f h rody Way�x�t 4s 10ccificd ,C[OW FIGURE C SB � Median /�!8 r � Fxisf 1�4�cn�cnt t�000scd Widcr�ing �-� �"xi5f t�ol�rncr�t' xisf 5h/dr. iZ' 7' P i' 7' lz' exist. 5hldr. t��7`Joint r 0.OS Exist Drain P' � , O ncl or —PrapoSGd Catoh l�sir� Catch C�5ir� HC in (5�� /�1o7c r�ur t3 J (5co Note F,gurc 8) TYP I CAL SECTION S d• 3992 -�oo '1`o Sid. �f-005 a- DO �}-a•�055 r 9v -fo Sf"c�.�{pg2 fi 3G.g x%sf. �4/c�i gc�5ir� 5f4.-n80 l 345.9 5td•-g/O/ -r �J7.6 O o fZPl170VCd r 6fa.-f/o/ -r- 97.G o 5fcl. 5E-4y75 t 00 -ro SSf4. I=F= �98 G o0 �k 5 Pion c t� D/7 4i27 } 97. Z =,E -g-775 ,- oO Starf/r7 Alt bra. •-¢o55 * 90 �x1,5t. 1=aVVner/t FIGURE D �. d N�'-� boc/nc! „Cants �xfend5 fo �1edion r � r-- f'ropos�l Shldr two c'-d Lan EF,0is f f�Vemer7t Abouf � 0.05 v� exist groin P' c O End or Witch sin ,At H9h FCYi 7f ' f i' i lxtc�fo exist ��n W l Nec� n, maxis f 9/v /r wiII Need -1 gher wing crud Orcrast ,Exist v/fch Will Nerd Magi f icaton. TYPICAL SECTION FIGURE E . i X , Jol l2' �X/5t n9 7 b 5h dr -ro)ty Lanc gox Cu/ve�'t pad �xlst Po�.�rr>enf Pxisf w1n Well 9 Exist Srcvsl- �y nInctrical About Wall O.02 1 � T OOOP Fom Gulvf( f Gbown No Modificatono '� 7o bviny qnd Srcast Wall ffltjulrcd TYPICAL SECTION FIGURE F CITY OF ' Dan Kelleher, Mayor 'r{ ✓ ., Don E. Wickstrom, P.E., Director of Public Works r t � ' RECEIVED JAN 2 2 1992 Street Cut Permits CTS ENGINEERS, INC. ' GENERAL INFORMATION RELATING TO INSURANCE REQUIREMENTS ' The Owner/Developer shall obtain and keep in force during the term of construction and throughout the specified term of maintenance, ' public liability and property damage insurance. This insurance shall provide coverage for the Owner/Developer, the Contractor, and all Subcontractors performing work on projects under City contract or authorized by City permit, as well as provide coverage for the ' City of Kent for the limits specified. i rya. The coverage so provided shall protect against claims for personal ' injuries, including accidental death, as well as claims for property damages which may arise from any act or omission of the Owner/Developer, the Contractor, the Subcontractor, or by anyone directly or indirectly employed by any of the parties involved. The minimum policy limits of such insurance shall be as follows: ' Bodily injury liability coverage with limits of not less than $400 , 000 for bodily injury, including accidental death to any one person, and subject to that limit for each person, in an amount of not less than $1, 000, 000 for each accident; and property damage coverage in an amount of not less than $200, 000 for each accident. The insurance must have reference to project name, project location, and contain "THE CITY OF KENT, ITS ELECTED AND/OR APPOINTED OFFICIALS, ITS EMPLOYEES, AND AGENTS ARE ADDITIONAL INSURED insofar as the work and obligations performed by City ' permit is concerned" . ' J262-90 II ■ .. KIM e1A ' 220 4th AVE. SO., /KENT, WASHINGTON 98032-5895/ENGINEERING (206)859-3383 FAX k 859-3559/OPERATIONS(206)859-3395 FAX#859-3664 INSTRUCTIONS FOR COMPLETING HYDRAULIC PROJECT APPLICATION FORM The Hydraulic Code (RCW 75.20.100 and 75.20.103) provides that in the event any person or government agency desires to construct any form of hydraulic project or other work that will use, divert, obstruct, or change the natural flow or bed of state ' waters or that will utilize any of the salt or fresh waters of the state or materials from the beds, must submit plans for the proposal to either the Department of Fisheries or the Department of Wildlife.These plans shall contain the general plans for this overall project and complete plans and specifications for work within the ordinary high water line. Written approval must be secured from the Department having jurisdiction over the site before commencing construction or work. ' For projects located in the following areas an application shall be submitted to the Department of Fisheries: Western Washington, which includes all lands lying west of the summit of the Cascade Mountains. ' All mainstream Snake River projects and all mainstream Columbia River projects downstream of Chief Joseph Dam. For projects located in the following areas an application shall be submitted to the Department of Wildlife: t Eastern Washington,which includes all lands lying east of the summit of the Cascade Mountains including Klickitat County, except as noted above. ' The application shall be mailed to the address of the appropriate agency. Department of Fisheries Department of Wildlife 115 General Administration Building 600 North Capitol Way Olympia, Washington 98504 Olympia, Washington 98504 ' (206) 753-6650 (206) 753-5897 The application shall include a vicinity plan and site plan of the project (cross-sections and profile shall be included when necessary). These should be attached. The reverse side of the form may be used as needed. An incomplete application may delay issuance of the approval. BLOCK 11. Enter only that portion of the project within the ordinary high water line, i.e., Culvert Installation, Bank Protection, etc. BLOCK 12. Identify water by legal or common name (if unknown, enter unknown) and first named receiving water. (i.e., Jones ' Creek, tributary Skagit River.) BLOCK 13. Enter legal description (section, township, range). If unknown, check with county auditor's office. BLOCK 20, The State Environmental Policy Act (SEPA) may require a determination of the environmental impacts of your proposal. If your project also requires a permit from another agency (state, city, or county) you may be required by them to complete an environmental checklist. If not, removal of 50 or more cubic yards of streambed material or a channel realignment may require a completed checklist. A determination of the impacts will be made from the information on this checklist as required by SEPA. Modifications to your project may be required to lessen any impacts. If this process has been completed, attach a copy of the determination or specify the agency and date.BY LAW,THE HYDRAULIC PROJECT APPROVAL CANNOT BE ISSUED PRIOR TO COMPLETION OF THE SEPA PROCESS. BLOCK 21. List other permits required. Identify by title and identification number. Examples are: ' Corps of Engineers (Federal) Water Rights; Flood Zone (Department of Ecology) Forest Practices (Department of Natural Resources) Shorelines, Building, Conditional Use (County or City) Water Quality Modifications — Any project which will affect water quality, including turbidity, may require an order from the Department of Ecology (DOE) authorizing a short-term modification of water quality standards. Applications for authorization should be submitted to the appropriate DOE regional office at least 30 days prior to starting your project. For additional information call (206) 459-6000. ' The completed forms should be submitted as far in advance as possible. Up to 45 days should be allowed for investigation and processing of the application. If you require information concerning your application, you should write or phone the appropriate department. GAM 11126 OX,1113 HYDRAULIC PROJECT APPLICATION Q (R.C.W. 75.20.100) DEPARTMENT OF WILDLIFE (R.C.W. 75.20.103) DEPARTMENT OF FISHERIES 600 Capitol Way North PLEASE PRINT OR TYPE General Admin. Bldg. Olympia, Washington 98504 Olympia, Washington 98504 (206) 753-5897 DO NOT WRITE IN SHADED AREA (206) 753-6650 ' tD LAST NAME FIRST to CONTACT PHONE(S) CONTROL NUM9ER f a� ✓3 STREET OR RURAL ROUTE 7< a i 9 WRIA y N yar �,p 9 ' CITY STATE ZIP 72 WATER TRIBUTARY TO II TYPE OF PROJECT ' OUARTER SECTION TOWNSHIP RANGE (E-W) COUNTY -• - -••- ------ ---• t3 SECTION _. _ _...... _ _._.._ .._... _.__.. ........ ...................................................................................... DESCRIPTION OF WORK 'METHOD' AND ;EQUIPMENT;,,.. _ ..................................................... .. .......................................................... .... .. .......................................................... ......................................................... .......................... ......... ................................... ....................... PROPOSED STARTING DATE PROPOSED FINISHING DATE 2D SEPA AGENCY/DATE OF DETERMINATION 21 OTHER PERMITS IT IS UNDERSTOOD THAT NO WORK WILL SIGNATURE DATE BE STARTED UNTIL A SIGNED APPROVAL IS RECEIVED TIME LIMITATIONS: 1 . ........ .. f1AM ,1 1 (n— W'ft') 771 y Date 1 Approved b T [� R h V it- OV � Data Bond mt. R q B dA e . $ Department of Public Wa 'rk Permit Fee ($25 Each Cut) ($30 Each Parallel Cut) Permit No A l��a �vn far treb and trivew u : . Rp.: . The undersigned (Pursuant to Ordinance No. 2202) hereby applies for permission to: Nature of work Number of cuts to be made Estimated starting date Location (Address) Tax Lot No. The work is to be completed within 90 days from date of permit. The project shall take not longer than 15 days to com- plete from the date of the street, driveway, or curb cut. (See conditions below.) Contractor ' Name Phone Work Home Address Date ' City State ZIP Washington State Contractor# Signature (I have read conditions below and agree) CONDITIONS ' TRAFFIC CONTROL PLAN MUST BE SUBMITTED AND APPROVED PRIOR TO ISSUANCE OF PERMIT. The following conditions also apply: ' O Complying with all City Ordinances, O Complying with Department of Public Works regulations, including all work described on traffic control plan. O Notlfying the City Inspector 24 hours In advance of the time the work will start,and when It will finish-859-3383. O Notifying any utility,emergency services,Metro,school or property owner subject to damage or inconvenience during performance of the work,and grantee shall make all arrangements necessary for the protection of any such utility or owner interest. ' O Prosecuting the work with diligence and with due respect to all property,contracts, persons,rights and the interests and convenience of the public. v Holding the City harmless from any and all damages which may accrue to any person or property because of this installation or maintenance. O Submittal of a sot of detailed plans of work. O All curb and street cuts shall be repaired to conform to the requirements of the"Standard Spocifications for Municipal Public Works Construction',latest ' edition,prepared by Washington state Chapter,American Public Works Association,and the latest construction standards of the City of Kent as set forth by City Ordinance,copies of which are on file with the City and available to the general public, or any additions or amendments thereto. O In addition to all other requirements specified by Ordinance 2202 or the"Standard Spocifications', the permittee shall be responsible for restoration of the street or curb to original or better condition. The permittee shall"finish patch"the street or curb cut immediately upon completion of the project. The permittee shall be responsible for defects or failure of the street or curb cut area for a period of one year following finish inspection. ' a The Construction Inspector may require that a temporary patch be made for 30 days and thereafter,a permanent patch will be placed by the permittee within 5 days. O Installation within the right-of-way shall be made by a method approved by the City Engineer. Cuts shall be made only in areas approvedby the City Engineer. All improved or unimproved areas within the right-of-way shall be restored to equal or better condition. o Signs,cones,barricades,and all other traffic control devices to protect and control podesvian and vehicular traffic in the construction area shall be used as prescribed by the Transportation Engineer and in accordance with the"Manual on Uniform Traffic Control Devices for Streets and Highways,Part V". A signing plan and/or traffic control plan shall be approved herewith. O Work during construction and restoration will be restricted in general to the hours between 8:30 a.m.and 3:00 p.m.and no work shall be allowed on the right-of-way on Saturdays,Sundays,or Holidays,unless otherwise authorized by the Transportation Engineer. City of Kent reserves the right to vary the ' previous stated times. Actual times may vary depending upon location and type of construction. O One or more traffic lanes shall be kept open at all times. Moving traffic shall be proporly controlled by trained,uniformed flagmen,if specified. O Excavated material shall be completely removed from the street surface. O Ingress and egress for vehicles and personnel to abutting property shall be maintained at all times. ' O Backfill and replacement of pavement or oiling of surface shall be done to the satisfaction of the City Engineer. Unless otherwise specified by the City Engineer, backfill material shall conform to"Standard Specifications for Municipal Public Works". e Filing of an approved surety indemnity bond or the equivalent to protect the City and approved public liability insurance naming the City as an additional insured in the amounts specified on the face of the permit. O A guarantee deposit in an amount as specified on the face of the permit to be made to the City. ' O Any inspection time in excess of one hour will be invoiced separately at the rate of$40.00 per hour. O This permit is temporary only,and all construction authorized hereunder is to be removed upon 30 days notice from the Director of Public Works. O Failure to comply with above conditions could result in being charged with a misdemeanor which could result in a maximum penalty of$1,000 or 1 year in jail. kHE CITY OF K E N T, WAS H I N G TO N APPLICATION FOR STREET USE PERMIT 1i'ursuant to City of Kent Ordinance #2286, no building permit or grade and fill permit shall be issued without rst obtaining a STREET USE PERMIT from the Public Works Department. Uis application must be completed and submitted to the City of Kent Engineering Department for approval prior the issuance of a STREET USE PERMIT. TYPE OF O RESIDENTIAL O OTHER (Explain) PROJECT: ❑COMMERCIAL PROJECT LOCATION: PROPERTY OWNER: ADDRESS PHONE NUMBER ------ "" CONTRACTOR NAME:(INCLUDE SUBCONTRACTORS BELOW) ADDRESS PHONE NUMBER WA ST CONTRACTOR'S NO CITY OF VENT BUS.LIC.i' SUBCONTRACTOR ADDRESS PHONE NUMBER WA ST CONTRACTOR'S NO. CITY OF VENT BUS.LIC.I SUB CONTRACTOR ADDRESS _ PHONE NUMBER WA.ST.CONTRACTOR'S NO. CITY OF KENT BUS LIC.1 LEGAL DESCRIPTION OF PROPERTY: (attach of lengthy) DESCRIPTION OF PROJECT: �pproximate Quantity of Fill Material Required Cubic Yards AUL ROUTE FOR GRADE & FILL OPERATIONS (if applicable) INCLUDE SKETCH OF PROPOSED ROUTE BELOW F: S 1, the undersigned, certify that the information provided above is true and complete. NAME(PLEASE PRINT) SIGNATURE By ' CITY OF AUBURN DEPARTMENT OF PUBLIC WORKS BUILDING DIVISION ' GRADING PERMIT APPLICATION BUILDING DIVISION PHONE: 931-3020 IIDATE SUBMITTED PROJECT NAME APPLICATION NO: I' 0WNER: PHONE/HM PHONE/WK (ADDRESS _ CITY/ST!?IP CONTRACTOR: PHONE PHONE/PRJ (ADDRESS CITY/ST!?IF' !STATE CONTRACTOR'S DEPT. OF REVENUE INDUSTRIAL INSURANCE IREGISTRATION NO. SALES TAX NO. ACCOUNT NO. ENGINEER: PHONE (ADDRESS CITY/ST/?iP ' ---------------------------------------------------------------------- ---------------------------j! II IISITE ADDRESS: PARCEL NO. REQUIRED: ;I �iL E 6 A L DESCRIPTION-------------- I 1u.ESCRI, TIuh 0- WORK. (ESTIMATED COMPLETIOIi DATE AMT OF FiLL AMOUNT EXPORTED i lIAMT. OF EXCAVATION MAX. DEPTH FILL SOIL RF'T BY IIMAX. DEPTH OF E't:C MAX. SLOE FILL ENG GEOL RPT BY I ij i AMOUNT IMPORTED PROJECT VALUE SLOPE E(C --------------------- ____—_--------- _ NOTE:l�1) This permit does not constitute approval or compliance with the rules, regulations, or requirements of any other urdiction, Which may relate to the above project. I2 Check With U.S. Army Corps of Engineers for possible permit requirements ,} remits are non-transferable. ' ik) HAUL ROUTES SHALL BE REQUIRED FOR ALL FILLS IN EXCESS OF 500 CUBIC YARDS. HAUL ROUTES SHALL BE SUBMITTED FOR APPROVAL PRIOR TO ISSUANCE OF THE GRADING PERMIT. !iI CERTi-Y THAT THE IN ORMATMN PURNISHED BY ME iS TRU!' AND CORRECT AND THAT THE APPLICABLE CITY OF AUBURN REQUIREMENTS WILL BE !!MET. II0wNERrA6EIiT RECEIVED BY 1 j NAME TITLE - ------------ IHI ji------------------------------------------------------------------------------------------= ----� ---------------------------------------------------------------------------------------------- �1FEE::: (FOR OFFICE USE ONLY) 11PLAN CHECK FEE PERMIT FED PLAN CHECK: RECEIPT NO _____—_______—___ r CITY OF AUBURN DEPARTMENT Y PUBLIC WORI BUILDING DIVI510N UTILITY PERMIT APPLICATION BUILDING DIVISION PHONE: 731-3020 ' DATE SUBMITTED --- PROJECT NAME— — -- APPLICATION NO: OWNER: PHONE/HM PHONE/WY, ' ADDRESS CITY/ST/TIP CONTRACTOR: PHONE PHONE/PRJ 1 ADDRESS CITY/ST/ZIF' CONTRACTORS STATE DEPT. OF REVENUE INDUSTRIAL INSURANCE REGISTRATION NO, SALES TAX NO. ACCOUNT NO. ' ENGINEER: PHONE ADDRESS CITY/ST!i1F' ' SITE ADDRESS: PARCEL NO. REQUIRED: LEGAL DESCRIPTION: ' WATER APPLICATION: — — NO. UNI—TS SERVED _---_ —SITE FIRE CONNECT -- ' --DOMESTIC USE YES NO SERVICE LOC. AUB SA OUT NO. OF:METERS -- IRRIGATION METER YES NO ' TYPE OF USE: RES CON OTH -- HYDRANT-PERMIT- YES �NO----- SEWER DEDUCT YES NO SIZE OF METER [TYPE ER dPPLICATION: -------_—�_ == --_ ---- — E SEWER YES NO NEW CONNECTION YES NO SIIE OF WATER METER OF USE RES CON OTH SEWER REPAIR/PUMP. REF' PHP ' STORM APPLICATION: — — TYPE OF CONNECTION NEW ADD ALT — TOTAL AREA OF PARCEL _—__—`SF PERCENT IMPERVIOUS _w— X TYPE OF USE RES CON OTH I CERTIFY THAT THE INFORMATION FURNISHED BY ME IS TRUE AND CORRECT AND THAT THE APPLICABLE CITY OF AUBURN REQUIREMENTS WILL BE MET. OWNER/AGENT NAME - TITLE RECEIVE➢ BYPHO -- ------ NE: NOTE: ALL OF THE FOLLOWING FEES ARE ESTIMATES BASED ON THE PRELIMINARY DRAWINGS. WATER FEES: (FOR OFFICE USE ONLY) WATER METER -- SDC — — --- SPRINKLER CONNECT.__ -- FILINa FEE --- ASS — WATER TAP --______ COUNTY INSPECTION TOTAL SEWER FEES: SEWER F'EkM1T SDC SEPTIC PUMP FILING FEE ASSESSMENT/AREA=-- — — SERER TAP ----- COUNTY COUNTY-INSPECTION—_�_INSPECTION—--...., '":TOTAL — -`— STORM FEES: STORM.PERMI1 —.....-- ASSESSMENT/AREA TOTAL APPROVA : UTILITIES ENG. — — WATER SUP.___--__ SEWER SUP^. _ —_ STORM ENG, CONST COOP.D. FIGURED BY — COPY MAILED TO OWNER: DATE____ _— NOTES TO BE TYPED ON PERMIT: i CITY OF RENTON Planning/Building/Public Works Department ' Earl Clymer, Mayor Lynn Guttmann,Administrator RECEIVED ' JUL 3 1 1991 July 30, 1991 ' Paul Prochaska, P.E., Vice President CTS Engineers, Inc. 2115 - 1 12th Avenue NE - Suite 100 ' Bellevue, WA 98004 SUBJECT: CITY OF RENTON DRAINAGE REVIEW OF SR-167 HOV PROJECT ' Dear Mr. Prochaska: The City of Renton appreciates having the opportunity to review the Washington State ' Department of Transportation (WSDOT) SR-167 HOV projects report, along with meetingwith 1 preliminary hydraulic you to discuss our drainage concerns related to the project. At this time, we want to formalize our review comments and the topics of our ' discussions during the June 20, 1991 meeting, and to provide information for the Springbrook Creek crossin of SR-1 67 and the proposed P-9 you with flow Channel/Panther Creek Wetland SR-167 crossing control structure as we discussed. The City has recenty obtained preliminary finds from a hydrologic model prepared for us by Northwest Hydraulic Consultants for the East Side Green River Watershed Plan using the HSPF (Hydrologic Simulation Program-FORTRAN) model. ' The existing drainage systems under SR-167 include a series of 12-inch to 30-inch crossing culverts under SR-1 which 1 carry the flows from the panther Creek Wetlands and Panther Creek to a unmaintained ditch on the west side of SR- 167. This condition has resulted in significant flooding problems, especially in the vicinity just north of SW 43rd Street. This runoff from the Panther Creek Wetlands and ' Panther Creek then enters City storm systems which directly outlet into Springbrook Creek. Improvements to the existing ditch along the westerly side of SR-167 could provide improved water quality benefits and possibly improve the local drainage problems in the vicinity described earlier. The City of Renton requests that the proposed P-9 Channel/Panther Creek Wetlands culvert under crossing of SR-167 be constructed as an important component of the SR- ' 167 HOV project. This facility has been identified as part of ates Department of Agriculture Soil Conservation Service and City of tRent nhe tEast ed S tSide Green River Watershed Plan since the early seventies. This would provide a defined 200 Mill Avenue South - Renton, Washington 98055 ' Paul Prochaska CTS Engineers, Inc. Page 2 drainage path that would allow hydrologic and wildlife corridor connection of Panther Creek and the Panther Creek Wetlands with 'Springbrook Creek which would allow fish passage small mammal immigration from Springbrook Creek to Panther Creek. Based on the HSPF model, the design flows for the 2, 10, 25, 50, and 100-year flood frequency from the Panther Creek Wetlands through the proposed P-9 Channel control culvert crossing of SR-167 is estimated to be 161 , 227, 264, 294, and 326 cfs respectively by Northwest Hydraulic Consultants with the HSPF model. The P-9 culvert should be designed to meet the King County Surface Water Design Manual (KCSWDM) requirements for capacity and fish passage using those flows and accounting for the ' effects of a maximum upstream and downstream water surface elevations (for 10 year flows and greater) of 16.0 and 14.5 NGVD respectively. Additional information regarding the P-9 Channel/Panther Creek Wetlands project can be reviewed in the projects Draft Interim Preliminary Engineering Report prepared by R. W. Beck and Associates for the City of Renton, which has been previously supplied to Alpha Engineers. The City also requests that the Springbrook Creek culvert crossing of SR-167 at South 192nd Street be improved for flood peak conveyance and sediment management, and ' has plugged several times during recent major storm events. This culvert crossing is a maintenance problem for both WSDOT and City of Renton maintenance crews, and has resulted in the stream diverting and flowing to the north along the easterly side of SR- ' 1 67 to the next crossing culvert which flows into a ditch on the west side of SR-1 67 in the City of Kent corporate limits. This ditch then flows to the north and enters a limited capacity storm system in SW 43rd Street that flows westerly to Springbrook Creek. This occurred on April 4, 1991 flooding of SW 43rd Street to depths of two to three feet. This condition jeopardizes public safety and we request that the Springbrook Creek culvert crossing of SR-167 at South 192nd Street be analyzed and a ' solution developed which eliminates this condition from recurring and keeps the stream in its natural drainage course and could even improve fish passage. ' Based on the HSPF model, the design flows for the 2, 10, 25, 50, and 100-year flood frequency flows of the Springbrook Creek crossing of SR-167 at South 192nd Street are estimated to be 43, 65, 78, 88, and 98 cfs respectively. The culvert crossing should be sized to accommodate these flows with the appropriate factor of safety and consideration given to sediment deposition into the system, fish passage, and entrance geometry as prescribed by the KCSWDM. This crossing culvert should be reviewed for ' placement on a more frequent maintenance schedule. We recommend that the existing and proposed storm and surface water systems analyzed and designed as part of the SR-167 HOV project be performed to meet the requirement contained with the KCSWDM. The project's hydrologic and hydraulic analysis report should address all of the KCSWDM Core Requirements and applicable Special Requirements. This includes providing water quality controls by biofiltration and/or wet ponds along with providing storm water runoff detention when required as specified in the KCSWDM. According to the KCSWDM on-site peak rate runoff control (detention/retention) will not be required for a proposed project provided that the Paul Prochaska ' CTS Engineers, Inc. Page 3 conditions for "Exemption From On-Site Peak Rate Runoff Control" are satisfied. We expect this will be the case for some portion of the proposed improvements ' The computational method to be used for sizing of runoff control (detention) facility sizing for basin of less than 25 acres should use the Santa Barbara Urban Hydrograph Method (SBUH) with the Level Pool Routing Method. The conveyance systems for basins of less than 25 acres can be analyzed and sized with the use of the Rational Method. Conveyance and detention facilities for basins of 25 acres and larger must be analyzed with the computational methods as specified on page 3.2-1 of the KCSWDM. If you require additional information or have any questions regarding this subject, or would like a follow-up meeting with yourselves and/or WSDOT staff, please contact Ron Straka at (206) 277-5547 or myself at 277-5548. Very truly yours, ' /;and ons, P.E., pity Engineering Supervisor rmwater and Wastewater Utility Section D:91-503:RP:RJS:ps CC: Richard J. Anderson, P.E., Utility Systems Division Manager Ron Straka,Storm Water Utility Civil Engineer Mary Lynne Myer,Principal Planner Rod Denticrdcr,P.E.,USDA Soil Conservation Service Mike Giscburt,P.E.,R.W.Beck and Associates Andy Levesque,Senior Engineer,King County Surface Water Management Division C S ENGINEERS, INC. ' REJ`JATA O. PROCHASKA.P.E. Precodur)L, PAUL PROCHASKA. P.E=. VrCC Pre::;rdcnt. ' MEETING CIVIL TRANSPORTATION August 2, 1991 STRUCTURAL WA State Dept. of Transportation WDOT Conference Room 26620 68th S. Kent, WA 98032 1:30 p.m. to 3:30 p.m. Attendees: *Jim Olsen, WDOT, 872-6470 ' *Gary Ward, WDOT, 872-6470 Ed Erickson, WDOT, 872-6470 Jack Gahan, CTS, Engineers, Inc., 455-7622 *Part-time. n WDOT's opinion Mill Creek needs to be cleaned and redefined. Also, between S 277th ' Street and the Green River it should be widened. The AR2 Ramp at SR 516: When the City built the abutting road their contractor, in order to miss a water main, installed a required culvert .7 high. This causes a backup of the storm water and flooding along SR 516 into state property. We discussed oil/water separators. I said I intended to install some where we have large contributing areas dumping directly into an existing creek. Their reply was; they already have two installed at the 212th Street and SR 167 Interchange, and were unable to maintain these structures as there is no place to dispose of the contaminated material. In the high fill area within the City of Kent, original design did not provide access along the toe of the slope to maintain the outfalls of the drain structures. Therefore, only minimum maintenance has been accomplished to-date. Where we are installing or replacing inlets; install catch basins, as these are easier to maintain. WDOT requested where there is existing curb and we are widening, install new curb; I said J we had intended to recommend that. v �'I { At South 212th Street we received construction drawings of the widening of South 212th under construction. WDOT has installed an additional 17&-eMP at approximately S-EW ramp 40+00, to help alleviate the ponding problem. In their opinion alot of the problem would be eliminated if the Dept. of Fisheries would allow W.DOT to-reconstruct-the-ditch- �'' along-the-S-E.W._ramp. {t, To improve the existing ditch along the southerly side of South 208th Street, west of SR 167, about 3001f of ditch needs to be regraded and 30 if of 18" dia. CMP installed. ' 2115-112th Avenue N.E. Surte 100 Tel: (2061 455-7622 Bellevue.WA 913004 FAX:[2061 462-1374 Culvert at L1015+00; the cities of Kent and Renton need to improve ditches, eg., clean upstream and downstream. In their opinion the existing culvert should be replaced with a ' 72" dia. pipe. Maintenance prefers a single culvert instead of double culverts, with a double culvert one always becomes clogged. In discussions, the overtopping of the West Valley Highway in the vicinity of Nendels Qighway 075+00) is that the storm sewer installed by the City of Kent under the West Valley is too small. ' These meeting notes are based on my recollection of the proceedings. If you have any modifications, clarifications or additions, please contact us as soon as possible. cc: File ' Attendees Tom Murawski -Alpha Engineers ' CITY OF AUBURN CENTENNIAL 1891 - 1991 IF �'1,,yc,r l�ul, Rur nrr ?5 Wrst N,1;,in St rcc[ Auburn,Was}lull;rcnl 98001-4998 1 ' July 29, 1991 4 E-CENE JUL 3 1 1991 ' Jack Gahan, P.E. , R. L.S. a'w' CTS Engineers, Inc. 2115 - 112th Ave. N.E. 1Suite 100 Bellevue, WA 98004 CC. f/G/ RE: SR 167 HOV Lane ' Dear Mr. Gahan: ' This letter confirms City of Auburn requirements regarding storm drainage facilities for the HOV lanes on SR 167 . The addition of impervious surface may adversely impact the area's drainage systems with regard to storm water quality ad quantity. As discussed in our meeting June 26, 1991, storm water treatment is necessary, and may be best served by utilizing biofiltration swales. Also discussed in our meeting was storm drainage detention requirements. Our position at this time was that storm drainage detention would most likely be required, depending on impacts. The additional 11. 80 acres of impervious area within Auburn City limits will indeed impact existing drainageways and potentially increase flooding. We discussed the use of several small detention ponds, and determined this may be impractical, due to increased costs, lack of available and functional land, ' environmental concerns, and unacceptable access and maintenance requirements. The most feasible and desirable solution to manage storm water generated with the increased strip of impervious area is with a regional detention facility approach. Because of the need created by the proposed HOV lanes, the State's participation could be actual regional detention facility ' land acquisition, design, and construction or equivalent substitutes via compensation and/or land acquisition provided to the City of Auburn. i 1 1 Jack Gahan, P.E. , R. L.S. ' July 29, 1991 Page 2 t I look forward to future correspondence regarding this issue, and can be reached at (206) 931-3010. Sincerely, tRod J. Linja, P.E. Utilities Engineer ' Department of Public Works RJL/bd cc: Frank A. Currie, Public Works Director Mary Seabrands, City Engineer Dennis Selle, Senior Engineer ' Tim Carlaw, Storm Drainage Engineer Steve Lancaster, Planning Director ' REF. E91-852 1 C-cs ' ENGINEERS, INC. RENATA O. PROCHASKA,P.E. MEETING: Pres.iu(�nj. ' PAUL PROCHASKA. R.E. July 10, 1991 3:00 p.m. Vice President Public Works Operations CIVIL 220 4th Ave. South TRANSPORTATION 1 STRUCTURAL Kent, Washington 98032-5895 (206) 859-3395 ATTENDEES: Nelden Hewitt- Utilities Superintendent City of Kent Jack Gahan- CI'S Engineers, Inc. ' 1. 30" culvert at 748+80 LM Line crossing from west to east. This could be part of the problem area that floods 70th Ave. South West Valley Highway) near Smith Farms. The problem exists, no apparent solution. suggested possibility for relieving part of ' the problem is a ditch along the west side of the freeway to the Green River. The pump station along the ditch east of the freeway at the Green River, belongs to ' the Union Pacific Railroad and does not work. The railroad tried to give it to the city about a year ago. The city, in turn, prepared a list of necessary repairs before the pump station would be acceptable. That was the last Mr. Hewitt has heard about the townership transfer. If this pump system is not working, the Green River should be backing storm runoff during high water and this could be effecting the 70th Ave. South flooding. 2. 24" culvert at L 796+65, on the east side of the freeway, water is standingin city ditch. Mr. Hewitt believes invert of pipe is too high. a y ' The ditch east of AR 2 ramp to Willis Ave. (SR 516) has been filled in due to improvements within the area. The storm runoff from the interchange runs through this ditch. This ditch must be reopened or the interchange storm runoff will have to be ' re-routed. 1 3. In the northwest corner of the interchange, along the DL 2 ramp, plans have been submitted to the City Planning Dept. for a shopping mall complex. According to Mr. Hewitt, the mall planners are installing an enclosed storm sewer system and incorporating the state highway storm drainage system, which will be connected to the 1 existing storm sewers in Washington Ave. (West Valley Highway). 4. At James Street, the roadway under the freeway floods and is closed during heavy rains. If it were possible to re-route thew freeway bridge drains to some place, other than James Street, it would be appreciated. 2115-112th Avenue N.E. Suroe 100 Tel: )206)455-7S22 ' ©r-Ilevu0e WA 9©004 FAX:)206)462-1374 1 ' 5. The culvert at L 842+55, running westerly of the railroad under the freeway, appears to be functioning well although flooding has been observed on the upstream side to James Street. 6. The twin 48" dia. culverts, at L 855+40, appear to be functioning quite well. ' 7. No apparent problems at North 4th Avenue. 8. At L 864+65, the twin 54" dia. culverts are functioning fine. It should be noted there is 1 not any access to the inflow or outflow of this culvert. If a problem arose with the culvert, access could be the bigger problem. 9. At 218th Street, along the westerly side of the freeway, someone is regrading the area and has buried all the culverts, but they said they would restore and regrade the ditch upon completion of their operations. 1 10. Near the bridge over Garrison Creek, stormwater overtops the S-EW ramp at So. 212th during heavy rains. No solution is apparent, yet Jim Olson of WDOT Area Maintenance (872-6470) might know the cause and already have a solution. ' 11. During the construction of the So. 208th Street overpass the southerly ditch along So. 208th, west of the freeway, was terminated. This now causes flooding within the area, ' therefore this ditch, or something else, must be replaced. 12. The culvert at L 1014+80, 192nd Street, becomes clogged from the sediment being carried from the ditch east of the freeway. Stilling basins or dams along the ditch will 1 have to be installed before we lose the freeway. The City of Renton could be doing something about this since they are aware of the problem. cc: File Attendees Tom Murawski-Alpha Engineers 1 1 i 1 CUS ENGINEERS, INC. ' RENATA O. PROCHASKA.P.E. PrC:;rdunL MEETING PAUL PROCHASKA. P.E. Vice. Pi•u--adunt: ' June 26, 1991 10 : 00 a.m. CIVIL 400 W. Gowe Street TRANSPORTATION 2nd Floor Conference Room STRUCTURAL ' Kent, WA 98032 Attendees : Tom Tazuma - Project Engineer, City of Kent Richard Chase - Water Quality Engr. , City of Kent Paul Prochaska V.P . , CTS Engineers, Inc. Jack Gahan, CTS Engineers, Inc. ' CTS received comments on proposed WSDOT HOV widening from Tom Tazuma, attached. The City requires some sort of retention/detention facilities with required wet ponds, maintain storm flow to existing conditions . For maintenance records or existing problem areas we were directed to Neldin Hewitt 859-3395 Maintenance Supervisor for the City of Kent. We received topographic survey maps with storm drainage ' facilities indicated for Section 31 T23N R5E; Sections 6, 7 & 18, T22N, R5E and Section 13, 24, 25, & 36, T22N, R5E. Also received the City of Kent Wetland Inventory Report - Phase I . ' These meeting notes are based on our recollection of the proceedings . If you have any modifications, clarifications or additions, please contact us as soon as possible. ' cc: File Attendees Tom Murawski - Alpha Engineers 2115-112ti Avenue N.E. Suite 100 7e1: (2061 455-7622 Bellevue.WA 90004 FAX:(206)462-1374 ' COMMENTS ON PROPOSED WSDOT HOV WIDENING Section 1 : Flooding of Mill Creek (Auburn) is directly adjacent to West side of SR 167 from south City Limits to the Green River bridge. . This may ' severely hamper proposed work since floodway cannot be filled without providing off setting conveyance capacity for the stream. 10 year release/25 year detention for new pavement and Q 25 year conveyance capacity downstream and biofiltration for a 2 year design storm are required. (No detention/retention is proposed for any of the 3 sections) . Section 2 : This section is subject to 100 year - 7 day storage requirement (equivalent to 8 1/2" of water over proposed project area in section 2 . ) . Release rate ' is for a 10 year storm. Conveyance capacity is for a 25 year storm. The use of the existing conveyance ditches for biofiltration may be possible if they are regraded to create a flat, vegetated channel invert and can meet the 2 year storm design standard. Section 3 : Detention in this region is for a 25 year storm with a 10 year release rate. The existing conveyance channel along the West side of SR 167 ' from S. 212th Street to S. 196th Street has been identified in the Kent Storm Comprehensive Plan as being substantially under capacity. An increase in ' capacity to 400 cfs is recommended. Water quality mitigation will be most critical in this section due to the proximity of `.Springbrook/Garrison Creeks. Wet ponds may be the best way to treat the storm water. C-cs ENGINEERS, INC. I-j1'_f.JATA O. PROCHASKA.P.E. Pr-C;:;iUcriL MEETING PAUL PROCHASKA. P.L. Vice Pre`.rdow. ' Attendees : Randall Parsons - utility Supervisor CIVIL City of Renton TRANSPORTATION Ronald Straka - Civil Engineer - City of Rent61fRUCTURAL Paul Prochaska - CTS Engineers, Inc. Jack Gahan - CTS Engineers, Inc. At: 11 : 00 a.m. 1st Floor Conference Room City Hall, City of Renton June 20, 1991 Re: Preliminary Hydraulic Report, SR 167 CTS received Storm Drain Comprehensive Plan and Hydraulic Capacity Calculations, Sheets 21 , 26 & 30; & Aerial Surveys ( 1962) for Sections 19, 30 & 31 , T23N, R5E, W.M. The City is more concerned with water quality than retention/detention, but problem areas are S . 192nd Street and S . W. 43rd. It was agreed that all calculations should be in accordance with ' King County Surface Water Design Manual. If the subbasins are less than 25 acres, use the rational method for determining runoff calculations . It was noted that if runoff was increased by less than 0 . 5 cfs for a 100-year Design Storm it is considered that the improvements have no effect upon the subbasin. It was agreed that the runoff parameters consider the existing ' freeway as it exists today, and the improvements are the addition of the HOV lanes . ' The City would like to see the state construct the P9 culvert under the freeway SR 167 within DOT right-of-way. The culvert should be designed in accordance with Chapter 4 of the King County Manual in regard to fish passages, e.g. , a minimum flow of t6" depth during low flow and 800 of culvert area during 100 year Design Storm, without overtopping the roadway section. Design should include the closure of the numerous smaller culverts through the freeway from the wetland area. It should be noted that if the state would construct the P9 ' culvert and make improvements within their R.O.W. , the City of Renton will take care of the completion of the offsite improvements required in the Comprehensive Storm Drainage Plan, ' within the Renton city limits The City would seal/plug the ' 2115-112th Avenue N.E. Suite 100 Tel: (2061 455-7622 Bellevue,WA 90004 FAX:(206)462-1374 culverts under the freeway, within the wetlands, at the proper time. All agreed the wetlands have to be maintained. ' Candid discussion noted that the HOV improvements would have little or no effect on the existing Storm Drainage Facilities. Some of the local problems would be resolved if the existing drainage ditch, along the westerly side of the freeway, would be cleaned, regraded, revegetated and the installation of a new fence. ' The City of Renton will provide CTS with flow data for the P9 channel and also for Springbrook Creek. Crossing of Springbrook Creek will definitely need improvement (See WDOT intra-department ' communication from Jim Olsen to Tom Lentz MS119 ) . These meeting notes are based on our recollection of the ' proceedings . If you have any modifications, clarifications, or additions, please contact us as soon as possible. ' cc: File Attendees Tom Murawski, - Alpha Engineers C-cs ENGINEERS, INC. RENATA O. PROCHASKA.P.E. N-e; adent, PAUL PROCHASKA. P.E. MEETING Vice: PreLode:nC ' CIVIL June 26, 1991 1 : 30 p.m. TRANSPORTATION 2nd Floor Conference Room STRUCTURAL ' City Hall 25 W. Main Street Auburn, WA 98002 ' Attendees : Rod Linja - Utilities Engineer, City of Auburn Tim Carlaw - Storm Drainage Engr. , City of Auburn Paul Prochaska, V.P. , CTS Engineers, Inc. Jack Gahan, CTS Engineers, Inc. CTS re?iedity of Auburn Comprehensive Drainage Plan. City requested quantity of additional impervious area to be added within the City of Auburn limits . I agreed to provide. ' There was no decision as to whether retention/detention would be required. We presented the suggestion of Andrew Levesque - SWN King County Senior Engineer, that we provide a regional detention pond in lieu of several detention ponds . They were receptive to the idea and would consider it. The City would require biofiltration swales and/or oil/water separators . They are using/requiring a coalescing plate oil/water separator on their projects . In their opinion a lot of maintenance would be required on the coalescing plate oil/water ' separator. They believed this type of oil/water separators would not be required by the WSDOT on SR167 . ' Grass-lined swales shall be designed in accordance with City of Auburn Design Criteria. ' These meeting notes are based on our recollection of the proceedings . If you have any modifications, clarifications or additions, please contact us as soon as possible. Note: 7/2/91 The existing impervious 68 . 30 Ac, HOV impervious 11 . 80Ac within the City of Auburn city limits eg. 15th St. S. W. to center line of S . 277th Street. ! cc: File Attendees Tom Murawski - Alpha Engineers 2115-112th Avenue N.E. Suite 100 Tel: 1206)455-7622 Bellevue,WA 90004 FAX:1206]462-1374 cts ENGINEERS, INC. f=3EP1ATA O. PROCHASI<A,P.E. Pre-Sldent PAUL PROCHASKA, P.E. MEETING: June 25, 1991 9 : 3 0 a.m. Vice President 701 Dexter Horton Building CIVIL 710 Second Avenue TRANSPORTATION e Seattle, WA STRUCTURAL ( 206) 296-6519 ATTENDEES : Andrew Levesque - Sr. Engr. SWM King County ' Paul Prochaska, V.P. CTS Engineers, Inc. Jack Gahan, CTS Engineers, Inc. ' Mr. Levesque, recommended, within interchanges where possible install a 48" diameter oil/water separator before storm drainage enters stream bed, or reroute existing drainage channels to ' provide added biofiltration length. He also recommended that it may be possible to provide regional detention in lieu of many local area detention ponds if acceptable to the local ' municipalities. He suggested we provide a wide flat bottom ditch section, with wet adapted grasses . Mr. Levesque will provide a list of ' applicable vegetation. In order to provide ditch section some slopes would require recutting. Where R.O.W. drains directly into an existing creek or creeks provide a level bench/cross slope before entering creek. At South 277th Street, station 43+00± the existing culvert is ' inadequate and storm water overtops the roadway. Mr. Levesque recommends an additional culvert be installed. ' Approaching the Green River on the westerly side, it was recommended that we provide a ditch through the number of low spots and maybe provide some relief for the low areas . Provide rock spalls on outfall of ditch into Green River. General statement, in order to provide the biofiltration ditch it may be required to purchase additional property. ' These meeting notes are based on our recollection of the proceedings . ` If you have any modifications, clarifications or additions, please contact us as soon as possible. cc: Files Attendees Tom Murawski - Alpha 2115-112th Avenue N.E. Suite 100 Tel: 12061 45J 7622 Bellevue,WA 90004 FAX:12061 462-1374 �.. . Cl ®T Depwbnent of ration Intra-Departmental Communication ' REC: EIVED Date: May 6, 1991 MAY 1.1 q 1991 ' From: Jihl—'�1Son o JIS ." 1 O•ERATICUS OFFICE Subject: SR 167 HOV PROJECT ' SPRINGBROOK CREEK, S. 192ND To: Tom Lentz MS 119 There is discussion and planning to add HOV lanes on SR 167 from Renton south. I am not sure what stage the planning may be in at this point but. want to identify a betterment item that should be considered in any proposed project. ' Springbrook Creek flows under SR 167 at S. 192nd Street, MP 23 .50. It is an important fish rearing stream for the Department of Fisheries, and ' a very sensitive location for Department maintenance. The problem is the usual, up stream development bringing gravel, debris and silts with the increasing immediate runoff. The flows come from county, passing through a portion of Renton, DOT, Kent and back to Renton. The Department of Fisheries is not pleased with any of the Agencies systems or the maintenance of these systems. DOT has a five year HPA, but we have ' had to seek emergency approvals three times this past season. Even with this attention the culvert blocked, requiring considerable additional maintenance funds. ' The existing culvert would handle todays storm flows, if sediment basins were constructed up stream. This is a regional problem involving King County, City of Renton, City of Kent and DOT. The Department of Fisheries ' will not allow the daily clearing of the culvert ends at SR 167, needed to maintain a functioning culvert. ' I suggest the existing 36 inch culvert be replaced with a much larger pipe. Current roadway grades and flow line elevation may require an elliptical design to gain capacity and maintain adequate cover. Input should be solicited from both cities and Fisheries. Access for maintenance equipment must be planned into any replacement culvert. If there are any questions please call Supervisor Gary ward, Don Komac or myself. ' JRO:te cc: file