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HomeMy WebLinkAboutSWP273218(13) City of Renton Strander Blvd. / FRB Coordination Meeting Agenda 5/31/05 1:00 PM • Project Update • Response or Clarification to City Comments Q� Offsite Drainage Basin Calculations o Luminaire poles and fixtures 6 Roadway profile and vertical curve s 7 o Irrigation & Landscaping clarification © Others?- • FRB/ City Coordination Issues o Irrigation and Service Connection Point o Erosion Control and Sediment Control d Stock Pile locations iS FRB Entrance and Curb Radiuses g/ Stormwater Details and Specs o Franchise Utility Installation E 1 {' i L E j t M WESTERN WASHINGTON HYDROLOGY MODEL V2 ✓�S ic—� Z ) Qc�w. 2'0,% PROJECT REPORT 1�L v S `I+�E H e£A _E-E7-JEAN Project Name: Strander Basin2+overpass Site Address: ity Renton r(eport Date 8/30/2004 Gage Seatac Data Start 1948 Data End 1998 Precip Scale: 1.00 PREDEVELOPED LAND USE Basin 2+ Flows To Point of Compliance Groundwater: No Land Use Acres TILL FOREST: 3.4 IMPERVIOUS: 1.1 DEVELOPED LAND USE Basin 2+ Flows To Pond 1 GroundWater: No .and Use Acres TILL GRASS: 0.6 IMPERVIOUS: 3.9 RCHRES (POND) INFORMATION Pond Name: Pond 1 Pond Type: Trapezoidal Pond Pond Flows to : Point of Compliance Pond Rain / Evap is not activated. Dimensions Depth: Oft. Bottom Length: 606.16ft. Bottom Width : 20.24ft. Side slope 1: 0 To 1 Side slope 2: 0 To 1 Side slope 3: 0 To 1 Side slope 4: 0 To 1 Volume at Riser Head: 0.845 acre-ft. Discharge Structure Riser Height: 3 ft. Riser Diameter: 18 in. NotchType Rectangular Notch Width 0.043 ft. otch Height: 1.334 ft. rifice 1 Diameter: 2.23 in. Elevation: 0 ft. Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.282 0.000 0.000 0.000 0.044 0.282 0.013 0.028 0.000 : 0.088 0.282 0.025 0.039 0.000 0.133 0.282 0.038 0.048 0.000 0.178 0.282 0.050 0.055 0.000 0.222 0.282 0.063 0.062 0.000 0.267 0.282 0.075 0.067 0.000 0.311 0.282 0.088 0.073 0.000 .356 0.282 0.100 0.078 0.000 -400 0.282 0.113 0.083 0.000 0.444 0.282 0.125 0.087 0.000 0.489 0.282 0.138 0.091 0.000 0.533 0.282 0.150 0.095 0.000 0.578 0.282 0.163 0.099 0.000 0.622 0.282 0.175 0.103 0.000 0.667 0.282 0. 188 0.107 0.000 0.711 0.282 0.200 0.110 0.000 0.756 0.282 0.213 0.114 0.000 0.800 0.282 0.225 0.117 0.000 0.844 0.282 0.238 0.120 0.000 0.889 0.282 0.250 0.123 0.000 0.933 0.282 0.263 0.126 0.000 0.978 0.282 0.275 0.129 0.000 1.022 0.282 0.288 0.132 0.000 1.067 0.282 0.300 0.135 0.000 1.111 0.282 0.313 0.138 0.000 1.156 0.282 0.325 0.140 0.000 1.200 0.282 0.338 0.143 0.000 1.244 0.282 0.350 0.146 0.000 1.289 0.282 0.363 0.148 0.000 1.333 0.282 0.376 0.151 0.000 1.378 0.282 0.388 0.153 0.000 1.422 0.282 0.401 0.156 0.000 1.467 0.282 0.413 0.158 0.000 1.511 0.282 0.426 0.161 0.000 1.556 0.282 0.438 0.163 0.000 1.600 0.282 0.451 0.165 0.000 .644 0.282 0.463 0.167 0.000 ..689 0.282 0.476 0.170 0.000 1.733 0.282 0.488 0.174 0.000 1.778 0.282 0.501 0.179 0.000 1.822 0.282 0.513 0.185 0.000 1.867 0.282 0.526 0.191 0.000 1.911 0.282 0.538 0.197 0.000 1.956 0.282 0.551 0.204 0.000 2.000 0.282 0.563 0.211 0.000 2.044 0.282 0.576 0.218 0.000 2.089 0.282 0.588 0.225 0.000 2.133 0.282 0.601 0.232 0.000 2.178 0.282 0.613 0.240 0.000 2.222 0.282 0.626 0.248 0.000 2.267 0.282 0.638 0.256 0.000 2.311 0.282 0.651 0.264 0.000 2.356 0.282 0.663 0.272 0.000 2.400 0.282 0.676 0.280 0.000 2.444 0.282 0.688 0.288 0.000 2.489 0.282 0.701 0.296 0.000 2.533 0.282 0.714 0.304 0.000 2.578 0.282 0.726 0.312 0.000 2.622 0.282 0.739 0.320 0.000 2.667 0.282 0.751 0.329 0.000 2.711 0.282 0.764 . 0.338 0.000 2.756 0.282 0.776 0.348 0.000 2.800 0.282 0.789 0.358 0.000 2.844 0.282 0.801 0.368 0.000 2.889 0.282 0.814 0.378 0.000 ,.933 0.282 0.826 0.388 0.000 .978 0.282 0.839 0.398 0.000 3.022 0.282 0.851 0.453 0.000 3.067 0.282 0.864 0.658 0.000 3.111 0.282 0.876 0.949 0.000 3.156 0.282 0.889 1.306 0.000 3.200 0.282 0.901 1.718 0.000 Z 944 n 9aI) n Qia 9 17A n nnn nR-7 3.289 0.282 0.926 2.683 0.000 3.333 0.282 0.939 3.227 0.000 3.378 0.282 0.951 3.809 0.000 3.422 0.282 0.964 4.427 0.000 3.467 0.282 0.976 5.078 0.000 3.511 0.282 0.989 5.760 0.000 .556 0.282 1.001 6.473 0.000 ­600 0.282 1.014 7.215 0.000 3.644 0.282 1.026 7.984 0.000 3.689 0.282 1.039 8.781 0.000 3.733 0.282 1.051 9.604 0.000 3.778 0.282 1.064 10.45 0.000 3.822 0.282 1.077 11.32 0.000 3.867 0.282 1.089 12.22 0.000 3.911 0.282 1.102 13.14 0.000 3.956 0.282 1.114 14.08 0.000 4.000 0.282 1.127 15.05 0.000 ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped Return Period Flow(cfs) 2 year 0.325211 5 year 0.411949 10 year 0.47101 25 year 0.547753 50 year 0.606578 100 year 0.666904 Flow Frequency Return Periods for Developed Unmitigated Return Period Flow(cfs) year 1.004981 year 1.22895 10 year 1.374348 25 year 1.556373 50 year 1.691407 100 year 1.826378 Flow Frequency Return Periods for Developed Mitigated Return Period Flow(cfs) 2 year 0.194122 5 year 0.287949 10 year 0.364716 25 year 0.480561 50 year 0.582036 100 year 0.697852 Yearly Peaks for Predeveloped and Developed-Mitigated Year Predeveloped Developed 1949 0.374 0.161 1950 0.595 0.188 1951 0.406 0.576 1952 0.270 0.143 1953 0.248 0.156 1954 0.316 0.165 1955 0.361 0.249 1956 0.355 0.186 1957 0.386 0.191 1958 0.311 0.166 959 0.247 0.171 �960 0.347 0.391 1961 0.288 0.175 1962 0.241 0.132 1963 0.281 0.169 1964 0.331 0.162 1965 0.278 0.189 1966 0.296 0.146 1967 0.399 0.216 1968 0.409 0.156 1969 0.287 0.164 1970 0.294 0.163 1971 0.276 0.187 972 0.463 0.291 _973 0.274 0.152 1974 0.281 0.154 1975 0.430 0.231 1976 0.288 0.170 1977 0.281 0.139 1978 0.365 0.179 1979 0.360 0.136 1980 0.358 0.312 1981 0.339 0.150 1982 0.514 0.485 1983 0.334 0.199 1984 0.301 0.141 1985 0.240 0.168 1986 0.440 0.354 1987 0.417 0.413 1988 0.206 0.149 1989 0.252 0.133 1990 0.649 0.414 1991 0.592 0.486 1992 0.300 0.152 1993 0.208 0.160 1994 0.207 0.122 1995 0.273 0.203 1996 0.483 0.439 1997 0.408 0.693 1998 0.314 0.163 'anked Yearly Peaks for Predeveloped and Developed-Mitigated .ank Predeveloped Developed 1 0.5951 0.5759 2 0.5923 0.4859 3 0.5136 0.4852 4 0.4832 0.4391 5 0.4632 0.4142 6 0.4396 0.4135 7 0.4303 0.3906 8 0.4168 0.3541 9 0.4095 0.3124 10 0.4077 0.2911 11 0.4061 0.2493 12 0.3989 0.2312 13 0.3860 0.2159 14 0.3740 0.2031 15 0.3645 0.1989 16 0.3608 0.1915 17 0.3602 0.1888 18 0.3580 0.1884 19 0.3553 0.1875 20 0.3466 0.1859 21 0.3391 0.1786 22 0.3339 0.1755 23 0.3311 0.1713 24 0.3158 0.1701 25 0.3143 0.1688 26 0.3106 0.1676 27 0.3011 0.1663 8 0.2997 0.1652 9 0.2958 0.1639 30 0.2939 0.1632 31 0.2876 0.1626 32 0.2876 0.1622 33 0.2870 0. 1609 34 0.2814 0.1601 �c n noi '� n ic�cc� 36 0.2811 0.1556 37 0.2779 0.1540 38 0.2762 0.1520 39 0.2739 0.1516 40 0.2728 0.1495 41 0.2697 0.1488 2 0.2517 0.1463 43 0.2479 0.1434 44 0.2471 0.1410 45 0.2411 0.1386 46 0.2398 0.1359 47 0.2080 0.1335 48 0.2065 0.1320 49 0.2060 0.1219 1/2 2 year to 50 year Flow(CFS) Predev Final Percentage Pass/Fail 0.1626 1378 1311 95.0 Pass 0.1671 1263 1045 82.0 Pass 0.1716 1190 911 76.0 Pass 0.1761 1079 833 77.0 Pass 0.1805 1001 755 75.0 Pass 0.1850 912 685 75.0 Pass 0.1895 858 638 74.0 Pass 0.1940 803 607 75.0 Pass 0.1985 748 548 73.0 Pass 0.2030 706 505 71.0 Pass 0.2075 628 463 73.0 Pass 0.2119 594 438 73.0 Pass 0.2164 540 412 76.0 Pass 0.2209 510 392 76.0 Pass 0.2254 470 371 78.0 Pass 0.2299 444 353 79.0 Pass 0.2344 414 331 79.0 Pass '.2388 393 316 80.0 Pass j.2433 358 302 84.0 Pass 0.2478 340 289 85.0 Pass 0.2523 313 270 86.0 Pass 0.2568 302 258 85.0 Pass 0.2613 280 246 87.0 Pass 0.2658 272 239 87.0 Pass 0.2702 251 224 89.0 Pass 0.2747 238 215 90.0 Pass 0.2792 216 199 92.0 Pass 0.2837 204 194 95.0 Pass 0.2882 192 182 94.0 Pass 0.2927 183 172 93.0 Pass 0.2971 173 163 94.0 Pass 0.3016 157 151 96.0 Pass 0.3061 146 140 95.0 Pass 0.3106 139 131 94.0 Pass 0.3151 127 124 97.0 Pass 0.3196 123 116 94.0 Pass 0.3241 113 109 96.0 Pass 0.3285 107 106 99.0 Pass 0.3330 97 97 100.0 Pass 0.3375 91 89 97.0 Pass 0.3420 83 89 107.0 Pass 0.3465 79 85 107.0 Pass 0.3510 74 79 106.0 Pass 0.3554 69 68 98.0 Pass 0.3599 63 61 96.0 Pass 0.3644 56 56 100.0 Pass -1.3689 54 53 98.0 Pass -).3734 49 48 97.0 Pass 0.3779 46 44 95.0 Pass 0.3823 42 39 92.0 Pass 0.3868 39 35 89.0 Pass 0.3913 39 29 74.0 Pass 0.3958 36 26 72.0 Pass n Anne 71 71 Qn n D--r 0.4048 30 24 80.0 Pass 0.4093 24 23 95.0 Pass 0.4137 23 21 91.0 Pass 0.4182 20 19 95.0 Pass 0.4227 20 19 95.0 Pass 0.4272 20 15 75.0 Pass .4317 18 15 83.0 Pass ,.4362 17 14 82.0 Pass 0.4406 15 13 86.0 Pass 0.4451 14 13 92.0 Pass 0.4496 14 13 92.0 Pass 0.4541 13 13 100.0 Pass 0.4586 12 13 108.0 Pass 0.4631 11 11 100.0 Pass 0.4676 10 11 110.0 Pass 0.4720 9 9 100.0 Pass 0.4765 9 9 100.0 Pass 0.4810 9 9 100.0 Pass 0.4855 8 8 100.0 Pass 0.4900 8 6 75.0 Pass 0.4945 8 6 75.0 Pass 0.4989 8 6 75.0 Pass 0.5034 8 6 75.0 Pass 0.5079 8 6 75.0 Pass 0.5124 8 5 62.0 Pass 0.5169 7 5 71.0 Pass 0.5214 7 5 71.0 Pass 0.5259 6 5 83.0 Pass 0.5303 6 5 83.0 Pass 0.5348 6 5 83.0 Pass 0.5393 6 4 66.0 Pass 0.5438 6 4 66.0 Pass 0.5483 6 4 66.0 Pass 0.5528 6 3 50.0 Pass 0.5572 6 3 50.0 Pass .5617 6 3 50.0 Pass -1.5662 6 3 50.0 Pass 0.5707 6 3 50.0 Pass 0.5752 6 3 50.0 Pass 0.5797 6 2 33.0 Pass 0.5842 6 2 33.0 Pass 0.5886 6 2 33.0 Pass 0.5931 4 2 50.0 Pass 0.5976 3 2 66.0 Pass 0.6021 3 2 66.0 Pass 0.6066 3 2 66.0 Pass Water Quality HMP Flow and Volume. on-line facility volume: 0.48 acre-feet S on-line facility target flow: 0.55 cfs. �(Q� )►1�(�F Adjusted for 15 min: 0.61 cfs. Off-line facility target flow: 0.31 cfs. Adjusted for 15 min: 0.35 cfs. 3 program and accompanying documentation as provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. AQUA TERRA Consultants and the Washington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall AQUA TERRA Consultants and/or the Washington State Department of Ecology be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the user of, or inability to use this program even if AQUA TERRA Consultants or the Washington State Department of Ecology has been advised of the possibility of such damages. PI 16. fi ���lI1III � � • "2y b51��-.V.cY4PJir I, 11 t •. III._ 1-•- �: #�I�IIIlh I r IiI11,Y�i� R b g7 ¢p7 ?Ili iF it 1111, �'un 3 st;.� sue % t q(I.�,�,.a �'• IxKP ur t � ' t••.a 3t1� i. �:i.;: t. tl g§g§ 11!p!p R i1iliiiir ,trp►� . �( � '�A�,�`'`t-'� �'��+� � icy �i�••dt�i`ry x�� ..��£�' +.� t . Springbrook Creek Storm Outfall & Drainage Design Elevation Data at SW 27 th Street (Datum: I NAVD) Previous Study New Study Drainage Design NHC 1996 Elevation Data ........... ................... 2-yr Future Flow Elev. :S cal 15.1 ft. ? 15.1 ft 25-yr Future Flow, Conveyance 17.9 ft. 25-yr Future flow, Storage V) 13.6 ft. sY/C y ? 100-yr Future Flow, Conve ance 19.2 ft. &.1/n.o17.5 ft. 100-yr Future Flow, Storage M 17.9 ft. 718.0 ft. Lowest Pavement Elev. 18.9 ft. Pipe.O.utfall into Sprin-gbrook Creek 9,7 ft, its b (4) ............. .................... &.10 :sang* To of Sand Filter, (Bottom Elev. + 4.0 ft.) 13.7 ft. Notes: (1) Water Surface Elevations as reported in the "East Side Green River Watershed Project", Final EIS, Sept. 1997, Table 7-2. (2) Conveyance event reflects a several local rainstorm without pumping restrictions at the BRPS due to high Green River flows. (Definition as provided in the Final EIS, Sept. 1997, See Note 1). (3) Storage event reflects a high Green River flow even in which the BRPS must restrict pumping rates in accordance with -G.RIA. (.Definition a,s,,pr,ov.i.d.e,d,,i.n...t.h.e..F.i.n,al.,EI,S.,,,.S.ept...1,99.7.,...S,e,e Note 1)..- ......... .............. ...... ..... ... ......... ................ .... . ............. ... ... ... ....... .................... (4) Critical Elva..On:f,or drain ago" a, e phfVIM tht 'be lowe ......(5) Any pipe slope to the outfall adds incrementally to this elevation. Perteet, Inc. Strander Blvd. (Job# 22044) Summary By Dean Franz, P.E. July 28, 2004 To: Rob Lochmiller, P.E. City of Renton RE: Drainage Design for Strander Blvd. Perteet Job #22044 Rob, As a follow-up to our phone conversation earlier today, I'm listing the elevation data on Springbrook Creek we've been using in the design for Strander Blvd. and SW 27th St. improvements. Due to the relatively flat road grades and high floodplain elevations for the creek, the proposed drainage structures have very limited height restrictions which creates a detention storage depth of only 2.5' to 3.0', which is causing the detention vault to be very large. A substantial amount of construction costs could be saved if we could lower the outfall elevation for detention and water quality facilities. So, it is worth revisiting this issue to check and see if we could make the detention vault outfall at a lower elevation. On a related note, we need to determine at what elevation we can have the outfall for the sand filter vault. Because a sand filter vault requires 4 ft. of drop (e.g. driving head across it), the depth requirements for this water quality structure alone is significant. The specifics are listed in the table below. Also, as I understand it, there is a study under way to update the Springbrook creek water elevations -- which further warrants looking at this issue. Your assistance in confirming the allowable outfall elevations for the water quality structures (e.g. sand filter) and the detention vault, is appreciated. If you need any additional information, feel free to call me. Thanks, Dean Franz, PE Perteet Inc. 425-252-7 7010, i 1-800-61 -9 900 ::AX:42�-3.i9-80?8 i 'w'v1'NV.F RiEEf.CO>,a 270-'Colby Ave:IW8, S-UitG 900 1 Everen,Washington 982 1 See table below. Perteet, Inc. Strander Blvd. (Job# 22044) Summary By Dean Franz, P.E. July 28, 2004 M0 lu U.S. Bancorp Tower, 111 SW 5th Avenue, Suite 2500 Portland, OR 97204(503)227-3251 FAX(503) 274-4681 Consulting Engineers MEETING NOTES PROJECT NAME: Federal Reserve Bank PROJECT NO.:303211 SUBJECT: Storm Drainage DATE: 10/6/04 ATTENDEES: (Company Name) (Fax Number) Ron Straka City of Renton-Storm Drainage 425-430-7241 Rob Lochmiller City of Renton -Transportation 425-430-7376 Allen Quynn City of Renton -Storm Drainage Matt Dolan KPFF 503-274-4681 Nalini Chandran KPFF— 503-274-4681 ADDITIONAL DISTRIBUTION: Randy Balducci- FRB; Tom Bauer- BOORA; Ryan Durkin- HCMP; Ron Rathburn-PBS ATTACHMENTS: FEMA map, City of Renton storm system The following is a summary of the storm drainage technical meeting held 10/6/04 at the City of Renton offices. The purpose of the meeting was to discuss the Federal Reserve Bank storm drainage and the proposed storm drain systems for Tract D and the southwest pond. Federal Reserve Bank Storm Drainage: • KPFF confirmed that the storm drainage for the FRB would be done to the 2001 design standards. Based on the latest site plan (dated 9/30/04), KPFF provided the following water quality and detention volumes that are being used for the FRB site: 1. Tract D— detention = 91,500 cf Water Quality = 18,650 cf(without 150% increase) 2. Southwest Pond —detention = 15,500 cf Water Quality= 3,150 cf(without 150% increase) These volumes are for the FRB site only and do not include the adjacent Boeing property or the Strander Blvd. addition. The pond cross section information and total volumes have been included at the end of the meeting minutes, as requested by the City. • KPFF stated that the calculations were done using the WWHM program (and confirmed by the KCRTS Level II analysis). The existing conditions are forested. Ron concurred with this approach. • The basin delineation for the southwest pond and Tract D were described. The southwest pond will treat and detain 1.4 acres of the FRB and Tract D will treat and detain 7.9 acres. C:IDOCUME-1laquynnlLOCALS-11TempICOR meeting- 10.6.04.doc October 11, 2004 Page 1 of 6 U.S. Bancorp Tower, 111 SW 5th Avenue, Suite 2500 Portland, OR 97204(503) 227-3251 FAX(503)274-4681 Consulting Engineers • In the wetpond volume calculations, the water quality volumes have been increased by 150% as stated in the Boeing Sverdrup report in lieu of doing biofiltration prior to discharge to the wetland. Ron stated that the ability to increase the volume by 150% is only allowed if we are using the 1990 King County manual, In the 1990 manual, special requirement#1 says that if a site is greater than 1 acre and if it discharges to a Level I or II stream, then the water quality volume can be increased by 150% in lieu of biofiltration. With the 2001 DOE standards, we would need to use their requirements, which says that if a "commercial site discharges to a fish-bearing stream, lakes, or to waters or conveyance systems tributary to a fish-bearing streams or lakes" then enhanced water quality treatment is required. The 2001 DOE does not allow the increase of the wetpond volume by 150%, Ron is to verify with the Department of Ecology if discharging to a wetland, would require enhanced treatment. If enhanced treatment is required, this would be a sand filter vault, basic sand filter, or media filter used in conjunction with a combined detention/wetpond (DOE manual, vol, V, p. 3-7). Ron said that there is some room to deviate from just these three enhanced treatment systems if we can prove that they are meeting the intended DOE objective. • KPFF asked about the use of Stormwater Management Inc. stormfilters. Ron said that they are not currently part of the city's code and would require a code change. They have been used in a few locations within the city, but the concern that the city has with them is the maintenance and sole sourcing. • For the Strander project, Perteet had mentioned using constructed wetlands for the second water quality treatment system. Rob will check with Perteet to see where this option came from, since it is not described in the 2001 DOE manual. • The outlet pipes from the FRB ponds can be in the wetland buffers but we will not be able to construct any sort of a filter strip or secondary water quality treatment system in the buffer. • The Tract D pond will need to be fenced since it is a public facility. Southwest pond: • For the southwest pond, the FRB will be using the 2001 DOE standards and the Boeing property will be at the 1990 standards. • Since the Boeing property is using the 1990 standards, they can increase the water quality volume by 150% in lieu of doing the enhanced treatment. This will not work for the FRB site however. • A storm drainage option that was discussed, and will be further evaluated by KPFF is to overdetain in Tract D and not do detention for the 1.4 acres of FRB property in the southwest pond. In this scenario, run-off from the FRB would go through a water quality system (i.e. bioswale, wetvault), through a secondary treatment(if required), and then to the wetland. The release from the Tract D pond would be decreased to compensate for not detaining the FRB area in the southwest pond. This would mean that the southwest pond would be designed to hold the volume for the Boeing site and the release rate into the wetland from this pond would be sized for the Boeing site using 1990 standards. • If the FRB wanted to, it could use the wetpond for water quality treatment. In this case, if enhanced treatment were required it would be done prior to going to the wetpond. Then the southwest pond would be sized volume wise to hold the FRB but the detention release rate would only be for the Boeing property (the FRB run-off would just be flowing in and out of the pond at an uncontrolled release rate). C:ID000ME-1laquynnVLOCALS- 11TempICOR meeting- 10.6.04.doc October 11, 2004 Page 2 of 6 U.S. Bancorp Tower, 111 SW 5th Avenue, Suite 2500 Portland, OR 97204(503) 227-3251 FAX(503)274-4681 Consulting Engineers • If we do decide to stick with the current plan of having the detention and water quality for the 1.4 acres of the FRB done in the southwest pond, then we will need to separate this run-off from the Boeing site. Due to the different standards, the discharge requirements into the wetland vary and can not be combined. Two separate outlet structures and ponds would need to be constructed. • To determine the Boeing detention and water quality volumes, the CN numbers and time of concentration from the Sverdrup report were used. Allen requested that KPFF relook at the time of concentration for the developed flow from the northwest corner of the site to the southwest pond assuming piped flow. • The use of Stormshed and SBUH for calculating the Boeing run-off is acceptable, per Ron. • The southwest pond will only need fencing if the side slopes are 2:1 or steeper. Strander • The water quality and detention volumes provided by the City to KPFF are based on preliminary calculations done by Perteet. They assume that the run-off conveyed to Tract D will come from the apex of the Strander bridge (at the railroad crossing) to the intersection of Strander and Oakesdale. The cross section taken in the calculations assumed that the roadway width would be constant through this area, even though it will actually narrow down as the road approaches the bridge. • The existing conditions were modeled to be forested, and 1.1 acres of impervious area were taken for the existing roadway. The volumes were calculated using WWHM. • Ron will e-mail KPFF Perteet's volume calculations for their information and record. Drainage Ditch • KPFF mentioned that it has come to the design team's attention that there is a drainage ditch going through the South Marsh which could connect the marsh to Springbrook Creek. • Ron and Allen provided KPFF a copy of the City of Renton storm system map. This map illustrates that there is a drainage ditch which comes from the south (near 43ro) up north thru the marsh to 2-30" culverts under Oakesdale Avenue. These culverts connect to the wetland on the east side of Oakesdale, which goes to Springbrook Creek. Ron said that there has always been a connection between the marsh and Springbrook Creek. • The water from the creek and tributary areas that come into the marsh feed the wetland. Our site contributes some but is a very small area in comparison to the others. • The ditch, south marsh, and Springbrook Creek are hydraulically connected. Floodplain • The floodplain elevations for the area are determined by Springbrook Creek and not by the Green River, since the Green River is levied. • The city is working on applying for an updated FEMA floodplain elevation, but they have not finished the process yet. C:IDOCUME-1laquynnV-OCALS-11TempICOR meeting-10.6.04.doc October 11, 2004 Page 3 of 6 LY2,69 U.S. Bancorp Tower, 111 SW 5th Avenue, Suite 2500 Portland, OR 97204(503)227-3251 FAX(503) 274-4681 Consulting Engineers • Ron provided KPFF a copy of the FEMA map with the correct street labels. The floodplain elevation at our site is 17.0, and it looks like there is a small portion of the parking lot which falls into the floodplain. If the building were in the floodplain, we would need to set the finished floor elevation 1' above 17.0'. The 17' elevation is determined using the NGVD '29 datum. Ron requested that KPFF determine what datum is being used in the project. • Ron also requested that Rob verify what datum is being used for the Strander project. (Note: After the meeting, it was determined that the Strander project is using NAVD 88 and the FRB project is using NGVD 29). The difference in elevation between the NGVD 29 datum and NAVD 88 datum is 3.58' (NGVD 29 + 3.58' = NAVD 88). • The City of Renton has their own requirement for compensatory storage. If we are filling in areas below an elevation of 15.6', then compensatory storage must be provided elsewhere. The FRB site is higher than 15.6' so this is not an issue. HPA • KPFF asked about the need for a HPA permit from the Dept. of Fisheries. • Ron said that a HPA is required if we are in state waters or in the ordinary high water mark. As long as we stay out of the wetland, the possibility that we need a HPA is very small. Wetland Covenant Restriction • The wetland restrictions will need to be discussed with development services. • The restrictive covenant was created as part of the Boeing EA, to compensate for wetlands that were being filled elsewhere on the Longacres site. Strander NEPA • The Strander roadway project has already submitted for NEPA, and it is expected to be complete by the end of the year. • Rob will check to see if the discipline reports need to be updated with the revised storm drainage (combining FRB and Strander at Tract D). Open Discussion • Ron mentioned that the City is doing a wetland mitigation bank, where there is currently structural fill that has to be removed. The schedule for this project is 2006, but it might be a good borrow source for structural fill for either Strander or the FRB. Detention/Water Quality Volume summaries: These are preliminary numbers based on the latest FRB site plan. The Strander numbers are from the city. The Boeing numbers do not reflect the revision to the time of concentration for developed conditions. The C:IDOCUME-1laquynnV-OCALS-11TempICOR meeting-10.6.04.doc October 11, 2004 Page 4of6 U.S. Bancorp Tower, 111 SW 5th Avenue, Suite 2500 Portland, OR 97204(503)227-3251 FAX(503)274-4681 Consulting Engineers total detention for the southwest pond is based on previous conversations where the Boeing and FRB site were going into one pond. • Tract D— overall detention = 128,400 cf FRB detention = 91,500 cf Strander detention = 36,900 cf Overall water quality= 39,650 cf FRB water quality = 18,650 cf Strander water quality = 21,000 cf Pond dimensions : Bottom of pond elevation = 11.5 (bottom of sediment storage) Top of Sediment= 12.5 Top of water quality/bottom of detention = 16 Top of detention = 20 Top of freeboard = 21 Discharge elevation to wetland buffer= 16 Datum for elevations = NGVD 29 Overall Tract D area= 1.2 ac • Southwest pond - Overall detention = 65,500 cf FRB detention = 15,500 cf Boeing Detention = 50,000 cf Overall water quality= 34,950 cf FRB water quality= 3,150 cf Boeing water quality = 31,800 cf Pond dimensions: Bottom of pond elevation = 11.5 (bottom of sediment storage) Top of Sediment= 12.5 Top of water quality/bottom of detention = 16.5 Top of detention = 20 Top of freeboard = 21 Discharge elevation to wetland buffer= 16.5 Datum for elevations = NGVD 29 Overall southwest pond area = 0.6 ac Action Items: 1. Ron will get back to KPFF by early next week on whether or not enhanced water quality treatment is required. 2. The city of Renton will check with Perteet if a constructed wetland will meet the DOE standards for secondary treatment. C:IDOCUME-1laquynnV-OCALS-11TempICOR meeting- 10.6.04.doc October 11, 2004 Page 5 of 6 U.S.Bancorp Tower, 111 SW 5th Avenue, Suite 2500 Portland, OR 97204(503)227-3251 FAX(503)274-4681 Consulting Engineers 3. KPFF will look at whether or not Tract D can be used to over detain for the FRB southwest pond. 4. KPFF will verify the datum used on the Longacres survey. Rob will verify the datum used for the Strander project. 5. Ron will send KPFF the Perteet water quality and detention volumes for Strander via e-mail. 6. KPFF will provide Ron a copy of the detention volume and water quality volumes (see information in meeting minutes). Information given to KPFF: FEMA floodplain map, storm drainage delineation Information given to the City of Renton: storm drainage basin map outline These meeting minutes represent KPFF's understanding of key points of discussion. Please provide any additions or corrections within one week. C:IDOCUME-1laquynnlLOCALS-11TempICOR meeting-10.6.04.doc October 11, 2004 Page 6 of 6 2707 Colby Ave Suite 900 Everett,WA 98201 ph. (425)252-7700 Fax(425)339-6018 www.perteet.com Perteet Engineering, Inc. Meeting Agenda Meeting Date: April 21,2004 Project: Strander Blvd. Perteet Engineering Project No. 22044 Subject: Drainage Design 1. Review of How We Got To This Point Ali t j d c u 51 L=Cv/a 2. Project Timeline and Critical Path Issue ?fc wr 3. Design Standards and Site Constraints 4. Drainage Detention&Water Quality Options ■ Costs ■ Pros-and-Cons 5. Phase 1-Road for Boeing Property 6. Interim Drainage Solution CADocuments and Settings\deanf.PERTEET\My DocumentsWeeting Agenda_Strander.doc facilities. Due to the sparse data available concerning dissolved metals removal in stormwater treatment facilities, a specific numeric removal efficiency goal could not be established at the time of publication. Instead, Ecology relied on available nationwide and local data, and knowledge of the pollutant removal mechanisms of treatment facilities to develop the list of options below. In addition, the choices are intended to achieve the Basic Treatment performance goal. The performance goal assumes that the facility is treating ston-nwater with dissolved Copper typically ranging from 0.003 to 0.02 mg/I, and dissolved Zinc ranging from 0.02 to 0.3 mg/l. The performance goal applies to the water quality design storm volume or flow rate, whichever is applicable, and on an annual average basis. The incremental portion of runoff in excess of the water quality design flow rate or volume can be routed around the facility (off-line treatment facilities), or can be passed through the facility(on-line treatment facilities) provided a net pollutant reduction is maintained. Ecology encourages the design and operation of treatment facilities that engage a bypass at flow rates higher than the water quality design flow rate as long as the reduction in dissolved metals loading exceeds that achieved with initiating bypass at the water quality design flow rate. Options: Any one of the following options may be chosen to satisfy the enhanced treatment requirement: Infiltration with appropriate pretreatment— See Chapter 7 • Infiltration treatment If infiltration is through soils meeting the minimum site suitability criteria for infiltration treatment (See Chapter 7), a presettling basin or a basic treatment facility can serve for pretreatment. • Infiltration preceded by Basic Treatment If infiltration is through soils that do not meet the soil suitability criteria for infiltration treatment, treatment must be provided by a basic treatment facility unless the soil and site fit the description in the next option below. • Infiltration preceded by Enhanced Treatment If the soils do not meet the soil suitability criteria and the infiltration site is within '/4 mile of a fish-bearing stream, a tributary to a fish-bearing stream, or a lake, treatment must be provided by one of the other treatment facility options listed below. +"' • Large Sand Filter—See Chapter 8 3-6 Volume V—Runoff Treatment BMPs August 2001 • Amended Sand Filter— See Chapter 12 Note: Processed steel fiber and crushed calcitic limestone are the only sand filter amendments for which Ecology has data that documents increased dissolved metals removal. Though Ecology is interested in obtaining additional data on the effectiveness of these amendments, local governments may exercise their judgment on the extent to which to allow their use. Stormwater Treatment Wetland — See Chapter 10 • Two Facility Treatment Trains — See Table 3.2 Table 3.2 --Treatment Trains for Dissolved Metals Removal First Basic Treatment Facility Second Treatment Facility Biofiltration Swale Basic Sand Filter or Sand Filter Vault or Media Filter"' Filter Strip Linear Sand Filter with no pre-settling cell needed Linear Sand Filter Filter Strip Basic Wetpond Basic Sand Filter or Sand Filter Vault or Media —' Filtee" Wetvault Basic Sand Filter or Sand Filter Vault or Media Filter" Basic Combined Detention/Wetpool Basic Sand Filter or Sand Filter Vault or Media Filter.. Basic Sand Filter or Sand Filter Vault Media Filter.. with a presettling cell if the filter isn't preceded by a detention facility Footnote: (1) The media must be of a nature that has the capability to remove dissolved metals effectively based on at least limited data. Ecology includes Stormfilter's TM leaf compost and zeolite media in this category. -3.5 Ba ' Treatment Menu OP `� Where Ap 'ed: The Basic Treatment enu is generally applied to: U"- \ \�� Project sites tha ischarge to a ground (see Step 3), UNLESS: — The soil suitabili c ' ria for infiltration treatment are met(see Chapter 7), or — The project u s infiltrate strictly for flow control —not treatment - and the ' charge is within -mile of a phosphorus sensitive lake (use t Phosphorus Treatment nu), or within '/4 mile of a fesh- b eng stream, or a lake (use the E anced Treatment Menu). • esidential projects not otherwise needing hosphorus control in Step 4 (See Chapter 2) as designated by USEPA, the Department of Ecology, or a local government; and August 2001 Volume V—Runoff Treatment BMPs 3-7 Apr 14,2004-5:15pm mickeyb J:\Trans_Design\22044-StranderBlvd\11_Hydraulics_Report\Developed Basin Map-Master.dwg Layout Name:Discipline Rpt G;r � w yWest Valle_ Fiy'J v v es" Valley Hwy tp C.M.S.T.P. I;I,I;I;I(1,1;1;1;1;1;1;1;1;I h;I,rl;1;1;I;I;I;1;1;1;1;1;1;1;1;1;1;1;1;1;1;I;1;I;I;1;I;I;I'I• , (n IiI;1;1i I;Ii�I 1;Ir1;1;1;1;1;1i 1�Ii I;1i�;1,'1;I;1,'t;,i'ti,;t;,1;,;1i,i 1;,�,;li,�,;,;,;,;1�, [✓y z •1.1 .T� I,I,IIa,,IL`I,Ir 1,1r 1,1, •ILL ,. -- \- 1t v_i I• ---c-' �, m Ir D !! \\ % �I 44 .I I ,r �qkesdalle A e SW _ .14f.............. •', �.. . ....... Cn HIGH POINT- •� ; N W v =r .- ..............f Cn Cn .ram .� I•+ z � 1 Rayn Springbrook Creek --- Cn O -4 (n :-. Cn Lind Ave. SW L ind A, .. SW v� N z Cn i � \ N,..� 7 J • , 4 W (n =r at Z Cn Cn I ' r E Valley Rd. E V'a 0 --t m — — _ N t zo - -- _ _ -- DD -i 0 m n O v — __--- rD f m n = = z 0 M s z o \ City of Renton FIGURE 4.4 R E N T O N Strander Boulevard Extension Perteet Engineering,Inc. Surface Water Quantity and Quality DEVELOPED BASIN MAP Civi4 Transportation and Snrvcying Technical Discipline Report BUILD ALTERNATIVES 1-3