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HomeMy WebLinkAboutSWP272249(1) ' RECEIVED ' DEC 2 7 1995 DEVELOPMENT PLANNING ' CITY OF RENTON STORM DRAINAGE ANALYSIS AND ' TECHNICAL INFORMATION REPORT ' PARKING ENHANCEMENT ' PACIFIC MEDICAL CENTER 601 S . Carr Road ' Renton , Washington 98055 1 Prepared by: AKB CONSULTING ENGINEERS ' 875 - 140TH AVENUE NE, SUITE 201 BELLEVUE, WASHINGTON 98005-3400 1 (206) 747-3592 DECEMBER 1995 ' B. PROJECT OVERVIEW: ' The df velopment is proposed to provide enhanced parking capacity for existing Pacific Medical Center Facility located on adjacent property. The development will result in 95 new parking stalls consisting of 33 compact stalls and 62 standard stalls. The total property area is 2.64 acres. Only a portion of this property is to be developed to meet current needs. Tile development proposes clearing only 1.35 acres of the property. Other portions of the property are to remain undisturbed. The total development area including a 0.26 acre haul road easement is 1.61 ' acres. Under the developed condition the proposed previous area is 0.81 acres. The paved afea proposed includes 0.14 acres existing haul, access road. New pavement proposed is only 0.66 acres. The development proposes to upgrade the existing access road to current city standard for a private access road. The access road is included in the surface water management system designs. The difficult site parameter is the existing slope of about 12% from the south- east to the nortli-west. To carve out a parking lot from this property was a challenging task, because the parking lot must be shaped as to be conducive and compatible to any future expansions west or south. The maximum slope of a parking pavement allowed by the city standards is 8%. Hence, cut and fill earthwork operations are required to achieve this slope. Looking at a larger picture, the slope was centered at the mid-depth of the property, such that, at build out the development is not skewed to the surroundings such as the existing haul road to the north. Centering the proposed slope at mid-depth of the property also contributes to the economy by avoiding retaining walls now and in the future. ' Page 1 of 2 King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET PROJECTPART I OWNER AND PART 2 PROJECT • • PROJECT • Project Owner P �f-ic. /rJEaicrl� Asir r2 Project Name RMC Polwt-l(r- �"Ntl P( mcNT ' Address So/ S. rfRee 4onO �H-roH Location Phone 326-402 Z Township 2� Project Engineer j}1MLr-S H Tn-r(j £. Range 5F ' Company /7 ENH(,W :RS2 1J4c.. _ _ Section 3/ Address Phone &7.5'-1"T4 RYr HE, (36ZGEvuE Project Size ��L— AC 747. 35�� Upstream Drainage Basin Size AC PART 3 TYPE OF APPLICATIONPART 4 OTHER 0 Subdivision 0 DOF/G HPA 0 Shoreline Management 0 Short Subdivision COE 404 Rockery 0 Grading DOE Dam Safety Structural Vaults [S?f Commercial 0 FEMA Floodplain Other Other _ COE Wetlands 0 HPA COMMUNITYPART 5 SITE - , Community 5oos c��� Drainage Basin PART 6 SITE CHARACTERISTICS ' 0 River 1 FloodP lain 0 Stream — 0 Wetlands 0 Critical Stream Reach ._ 0 Seeps/Springs — 0 Depressions/Swales 0 High Groundwater Table 0 Lake Groundwater Recharge — ' 0 Steep Slopes —._ _ 0 Other C 1 Lakeside/Erosion Hazard . SOILSPART 7 ' Soil Type Slopes Erosion Potential Erosive Velocities 1 t q 12L:t _ lrnJ fo lYk�-,li�iNt 0 Additional Sheets Attatched F��ru2C 1/90 Page 2 of 2 King County Building and Land Development Division TECHNICAL INFORMATION REPORT (TIR) WORKSHEET DEVELOPMENTPART 8 • REFERENCE LIMITATION/SITE CONSTRAINT Ch.4-Downstream Analysis 0 _ o - -- ' 0 Additional Sheets Attatched PART 9 ESC REOUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION FOLLOWING CONSTRUCTION Sedimentation Facilities F_Y�l Stabilize Exposed Surface Stabilized Construction Entrance Remove and Restore Temporary ESC Facilities Perimeter Runoff Control [./ Clean and Remove All Silt and Debris Clearing and Grading Restrictions Ensure Operation of Permanent Facilities Cover Practices Flag Limits of NGPES EX Construction Sequence Other � Other -- — -- --•----- ----------- PART 10 SURFACE WATER SYSTEM Grass Lined Channel Tank Infiltration Meth od of Analysis 0 Pipe System Vault Depression Open Channel CJ Energy Dissapator Flow Dispersal Compensation/Mitigation t�Cl Dry Pond C] Wetland Waiver of Eliminated Site Storage El Wet Pond E—] Stream EJ Regional Detention N-A - ' Brief Description of System Operation Pf�/IK/�lCt /ZiC' _7-o Dey D15-7ENT/ON PoND ys-r/,y4- onAiNd{iZ��y 7L . Facility Related Site Limitations [] Additional Sheets Attatched ' Reference Facility Limitation PART11 STRUCTURAL ANALYSIS ART 12 EASEMENTS/TRACTS (May require special structural-review) _) Drainage Easement L_) Cast in Place Vault E::1 Other C] Access Easement Retaining Wall 0 Native Growth Protection Easement —) Rockery>4'High Tract 0 Structural on Steep Slope F-1 Other ' PART 14 SIGNATUREOF - • • I or a civil engineer under my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attatchments. To the best of my knowledge the information provided here is accurate. ---_- I u)�I�fl• fir,{ {�' 4 "' ! Is511• •� �� E�ti 7+y, �,�;,z T,t'y'��E x.,•`:;' ,r.'•r,`;+. S ' %fsil A IiStH G �• S'16T11 ST { �' •. r a �e'T OR . 1 l-ir I 1� i <+�i !1: Ydl♦'!�.�5, S 1 I J 1� � • �. y •.t7 E�. IL LXII'�^�a��yy'a,�v�3 Y��;•� �r t ;� sr :•.. p d �� ,.` * :x .y4i`- r '' ! 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SITE ; I•SE s .N SE IBITH" Si I ' SE L I861N ST SE 1B6TN ST REN' —� _S[U7M s < 188TN S BBM ST 5 IB7TN ST .;�,i!+f!• , I � s, c%Sr Ct $t I897N T <:s' 790/H S 190iH_S7 V.T• SI 1" n x IV:- N 1 L M.r 12N0 si _ '2 s S 55T11 s' T. 3 SE _ = 192ND["- ST I _--- , iE 3 S 9)191M SW 194TH ST ' -4�-Ic-'�—=i-- �''• co T/�•• ' S 196TH ST yS iH ST 1 '1••_____ u lr1 141N ST ' SS S 1981H ST st SE IfBM- ttQx SE S -is 2oDTN ST > S 200TH ' "TT -!= SE 200TH ST `I �I I s _ 9800 • 5 � SE 21 > Dro sT ' � I v'll I Pii' y c NHi mm ST 1 ) ) S '202ND. ------ -- - ! _j .aL 201RD ST KfSE MRDt�1 ST 2047Nlil ST I 'm .�'., I'll♦ S I . s"ITNr-r toy '<E 2NNR"' a t a' erF Q ` T ►AwnEEB ice$$ `e'' i I Sty 07M ST- A 206 PL CfY7Gt nn 'iac;r ��') S:• ' S 208 1 $ x Bonn Lt �= st Z „ s 209TN $ SE t 208TH r ST 5 209 s`�`^ 3f?� a. s il.ti 3t" r Iaetc REFERENCE: THE THOMAS GUIDE, KING COUNTY, WASHINGTON, PAGES 655, 656, 685 AND 686, 1995 EDITION. VICINITY MAP PACIFIC MEDICAL CENTER PARKING LOT ' RENTON, WASHINGTON FIGu,pe 2 P •I r Lil- lis32 / I�LI7 �. 5 2 3 7 I L:o CP PC N^K� j%' 'Lt, 35u Ac P.; � 'S. 177TH ST. e.9 C i 5 o 10 12 ; _�_ Ronald 31 - W. S c t t II 1 / t / i' %/� QO r/•l l 716 5 S o 3.28 AC.1Nul 16 / (� m/ 2 7 �� .g l l j 3 41 l ./ ,•/ro a o 24 '(� 40 \� 42 76 H DR 23 21,: �l r y Sn c t zo 2 s.o I 2 b I7 �79 .1 ;"I,=`22 fA117� 20 -71 j/ y r, ,30' goo /')•.51�` ~ 45 44 43 �I S.P.t1276056 R l S F.I2820437 93 l� t trI ♦ •' ' �5 —>bl lC.. •I,. y tt}' t.. __ .� la.r>• � �"1 y� .I� / l ,'•1/ u t Ur:S-1 l/G� 1 f�'< 2e / •s g ,r3�j¢�sL/'/,��,,�� t i // _� (I) •nl ` V SKJt ',�.';`ttpy� r .eyyt�r+, I 61✓ N I ,. t �' :i ,Z�qc r t4 t qJ°� '•./ � 10�IS 15)�. J �.;,•�c�i �,� � t f. 2.�:AC.I /.� .ice \\ r� ® - t� � ♦ ,£ + O o-,oa '"' � y G -• •'J � 1�2 ; � .J°., � � ; �1��XI NFL �t I�• I I � I. a i C) J co vvash�ngton 2 ;Dr ingorcoc �. •I �ands_In.c_. 2 50 Ac I :�' 6: -.5Z Ac. � B4 I —trGcs-- y, Volley Vllio I ��\ ❑ Convalescent 2.31 Ac. /6 NORTH �. W Shegrud 0.63 Ac.2-: 2 Ac. � c 69 gq i S1 _31 _ Stafe of Washincton F/&V/05 1111 2. s 1 ' rr � SY:,1.1 '+ o I I•-' I �a rai i i � I j pt nT PACIFIC MEDICAL CENTER. � RENTON, WA. peRNwN,•o,wn,asm 7 _ CONSULTING ENGINEER. TEMPORARY ERROSION/SEDIMENTATION CONTROL PLAN. 8 3d'ry9/-,d , I I lTf �JLLI I I I I I I I I I I i I e•• '� ) � I} I� ') i,� �x �'.4 V h a- fi,j'//��� � I•' '.11 1.��r. ��� is., 7$". C;' � I ( �.e I .i;i �, I �J..I.'f•1 �� / /- `/i JIB 5 , .a... Iz z I I Ts l �, 4 is ", I I i 'I J r .. 1 s:�" a J �� ��:_ .� '.I r •. ' \t1 i •�e ;� t'kA ttt,S!1 ` c j V � � Ss I r• ' l � j it it � l ��,/;/. � ' �' I' I � Ii11. I ., ; ` ► � ryi 6s � kltt�' a 3 is I i PAVING, GRADING, AND DRAINAGE PLAN i'MC zop,.dnh A-sM,an j t PROPOSED PARKING ENHANCEMENT YncTrsc Ms ntenT CQvrPR sea+ua wsmNlnn I �r Ropcl M�nspxmanl Sxxk. Imo':i'e„ (ranb ns+p..i n x .,x e x n i x s e in I'i I FPON : DEL ERICk:SOH P.E. PHOI IE 1,10. 74 r 5:325 POPu we 1 •} '' F4 , sty;►, Or 7 r . ;u 17 J rr wa '1 W. •t M�94 S a° •� ? I A.n�S 1 M r Q J! f~6 1 1 { Py ' ' Ne b 1 •;ti 1 ' y �r l oil D^ •� Ilr H! .i Br RallA,I► c. . • • t. ',ar 9 t� •: VVn G i,• m y7f�r Ur Py Oa Ro •f.t, w� •1i1'� ` 1! ► ,4; a• a+ Ad �� __—� t _ �.-- 1■ _-__ Me. t ,��•� it � Ru �� • • .. �_ Nlg No k. Pv ja tAICC c .. Pk ah Pk, Or - - w r ••B '• N �'rb d NX Pr •Wry = ABC An,C wo a•. - t S a E o t Ur1 a Re I 07 ; AMC t • A C: ... �--•!�-�t., w NO ? 1 a 2 ; :#I-+ OS vu It • IN '��. + ,2 p +� / `1, A`C 25' wo wo My t .1 ! Aeq �; Am AmC sly, AmrC. nO O* V' (F AX l sk r� AY C rA&C 1' • s _ y i•. 1, t Pu , Am t• rv.' F •.. A C Am0 1' Py wo p7 Jr tJ- k Br •l� —*3 - t. • ,E, . .r� Pk 31 . •• ! t . O »�• t t 4 Re AN AgI3 R• U* ° { •• •� r l • yy fEEt t',: _ •��J a t�, .+-�. ._.r Y ••.:_ { tl � AkF 05 � • 4 , O% � ,� •�' � • Ago Am i� • tJr I 1 15ep IL KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL ' (2) CN values can be area weighted when they apply to pervious areas of similar CN's (within 20 CN points). However, high CN areas should not be combined with low CN areas (unless the low CN areas are less than 1 5% of the subbasin). In this case, separate hydrographs should be generated and summed to form one hydrograph. FIGURE;3.5.2A IIYDROLOGIC SOIL GROUP OF THE SOILS INKING COUNTY HYDROLOGIC HYDROLOGIC SOIL GROUP GROUP* SOIL GROUP GROUP* Alderwood C Orcas Peat D Arents, Alderwood Material C Oridia D Arents, Everett Material B Ovall C Beausite C Pilchuck C Bellingham D Puget D Briscot D Puyallup B Buckley D Ragnar B Coastal Beaches Variable Renton D Earimont Silt Loam D Riverwash Variable ' Edgewick C Salal C Everett A/B 'Sammamish D Indianola A Seattle D Kitsap C Shacar D ' Klaus C Si Silt C Mixed Alluvial Land Variable Snohomish D Neilton A Sultan C Newberg B Tukwila D Nooksack C Urban Variable Normal Sandy Loam D Woodinville D HYDROLOGIC SOIL GROUP CLASSIFICATIONS A. (Low runoff potential). Soils having high infiltration rates, even when thoroughly wetted, and consisting chiefly of deep, well-to-excessively drained sands or gravels. These soils have a high rate of water transmission. B. (Moderately low runoff potential). Soils having moderate infiltration rates when thoroughly wetted, and consisting chiefly of moderately fine to moderately coarse textures. These soils have a moderate rate of water transmission. C. (Moderately high runoff potential). Soils having slow infiltration rates when thoroughly wetted, and ' consisting chiefly of soils with a layer that impedes downward movement of water, or soils with moderately fine to fine textures. These soils have a slow rate of water transmission. D. (High runoff potential). Soils having very slow infiltration rates when thoroughly wetted and consisting chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a hardpan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a very slow rate of water transmission. ' From SCS, TR-55, Second Edition, June 1986, Exhibit A-1. Revisions made from SCS, Soil Interpretation Record, Form #5, September 1988. 3.5.2-2 11/92 SITE DRAINAGE FEATURES EXISTING: Existing Site Topography is such that the site runoff sheet flows down unifonn slope from the soutli-east to the north-west. The natural discharge location appears to be at the northwest corner of the site to an existing inlet to an existing 18" concrete pipe. This 18" concrete pipe appears to convey the drainage from the property to the east of the project site as shown in figure 3A. PROPOSED CONDITION: Under proposed condition the runoff route remains virtually the same, sheet flowing from the south-east corner to the north-west. The runoff sheet flows from the pavement into the biofiltration swale along the west side of the parking through curb cuts. The biofiltratiion swale conveys the runoff to the detention pond at the north-west corner. The controlled discharge is through the control structure to the existing inlet to the west. The direction of runoff and the location of the discharge remain unchanged after development. The offsite runoff from the upstreamn property to the east remains unaltered. The upstream runoff is intercepted by an existing drainage ditch located along the east property line and conveyed to an existing stonn drainage system consisting of an 18" concrete pipe. The drainage flows north through the existing Pacific Medical Center Development, through a series of drainage structures. ' CORE AND SPECIAL REQUIREMENTS CORE REQUIREMENT #I: DISCHARGE AT NATURAL LOCATION Under the existing conditions the onsite runoff route is from the south-east to ' the north-west corner. The discharge is at the north-west corner of the property. This is well depicted in figure 3A. The proposed parking pavement slopes from the south-east corner to the north-west as depicted in Figure 3B. The runoff is collected in a biofiltration Swale flowing north and west to the detention pond. The detention pond is located at the north-west corner of the property. The discharge from the detention pond is proposed through the control structure to the same location as the pre-development discharge point. The inlet located at the north-west confer of the property is the receiving point of the discharge from the control structure. ' CORE REQUIREMENT # 2: OFF SITE ANALYSIS The upstream property under existing conditions has a drainage ditch that runs along the east property line. This ditch effectively intercepts the nmoff from the upstream property, diverts it north and conveys it to an existing storin drainage system consisting of an 18" concrete pipe. This sewer conveys all upstream drainage without any interference from the development. ' The discharge from the development is to the same inlet at the north-west corner of the property that receives discharge from the property under existing conditions. The rate of discharge from the development is controlled by the control structure to not exceed the pre-development rate at all storm events up to and including the 100 year 24 hour storm event. In fact using the 30% enlargement factor the discharge is limited to 0.68 cfs as compared to 0.75 cfs under the existing conditions. Therefore, 0.68 efs is the highest rate of discharge proposed up to the 100 year 24 hour stonn event. The drainage system receiving the discharge from this development consists of an 18" concrete pipe at 7.5% slope. The non-surcharged capacity of this system tis calculated to be about 30.7 cfs. The proposed discharge is merely 2% of the capacity. The 18" concrete pipe flows west along the access road and runs in to a drainage system along Carr Road and Talbot Road, leading to Panther Creek drainage system. This system is not known to have existing drainage problems and because the discharge from the development is restricted to less than the rate under existing conditions, the downstream drainage system is not expected to be adversely affected. ' CORE REQUIREMENT #3: RUNOFF CONTROL The project proposes to provide about 0.66 acres of new asphalt parking. P p g Therefore, a biofiltration swale is a core requirement. A biofiltration swale is ' proposed along the west edge of the parking pavement. The runoff sheet flows across the width of the pavement and through the cuts provided in the curb and is received by the biofiltration swale. The biofiltration swale conveys the runoff to the detention system. The peak rate runoff control is achieved by means of a control structure located at the north- west corner of the detention pond. The control orifices are sized such that the discharges do not exceed the pre-development rates. The stage discharge tables attached clearly indicates this. t ' CORE REQUIREMENT #4: CONVEYANCE SYSTEM The conveyance system such as the biofiltration swale and the P drainage pipes have adequate capacity to handle drainage volumes at least up to the volume igenerated under a 25 year 24 hour storm event. The drainage calculations attached indicate the verification of the capacity of biofiltration swale to adequately convey 1.89 cfs which is greater than the 100 year 24 hour runoff from the entire development site. Sufficient free board allowance exists even at these flow ' volumes. The 12" concrete pipe is the discharge conduit provided from the control structure at 7.7% slope. A 12" concrete or a PVC pipe can convey 2.72 cfs drainage volume even at 0.5% slope. This capacity exceeds the flows expected at the highest storm the system is designed for. CORE REQUIREMENT # 5: EROSION/SEDIMENTATION CONTROL PLAN ' Erosion and sedimentation control is considered to be of high priority. b P Y Therefore, all preventive measures which could reasonably be taken have been proposed. The best management practices employed include: A. The extent of clearing is minimized. ' B. Diversion swales are proposed to route surface water runoff around the disturbed areas. ' C. A stabilized constriction entrance is proposed. D. The drainage inlets, located downstream and considered likely to be impacted, are to be protected with a filter fabric cover over them, to keep sediment laden water from entering the existing storm sewers. E. A sedimentation trap is incorporated in to the design to allow sediments to ' settle in the basin provided. F. Moderate slopes of 3H:1 V are proposed for almost all created slopes. G. Silt fences are located at downstream extremities of the cleared area. H. All created slopes will be planted or 11 droseeded within a week of ' constriction. 1 SPECIAL REQUIREMENT #1• CRITICAL DRAINAGE AREAS The review of Kin Count Sensitive Areas Ma Folio does not indicate g Y p d cate presence of any critical areas on or in the immediate vicinity of the site. SPECIAL REQUIREMENT #5• SPECIAL WATER QUALITY CONTROLS The project does not propose more th n P J p p a one acre of nnpervious stuface 1 subject to vehicular use. SPECIAL REQUIREMENT #11&12• GEOTECH. ANALYSIS AND REPORT S� o W,,, The project does not propose an infiltration system nor does it contain steep ' lopes. However, a geotechnical investigation was conducted on site for general development purposes. A report is attached. SPECIAL REQUIREMENT #13: AQUIFER PROTECTION AREAS The project is not proposed within an aquifer protection area. ' DRAINAGE CALCULATIONS 1 For: tProject: Pacific Medical Center Parking Location: 601 S. Carr Road Renton, Washington, 98055 ' Client: Ms. Vicki Somppi, P.M. 1 Pacific Medical Center 1200 12th Avenue South Seattle, Washignton 98144 By: Shailesh Tatu, P.E. December 1995 ' Job Number: be . 95071 1 1 1 r �ffUG %rro Z;,�5—2Z 17 r r r �k�as�-t� �c,>>7 U /oa✓i'3c�dY/YlTS = �7� ��'° maxis>�✓✓C� ,t?�.t�ty — 5 9 �v �� r r F"ni� C-xi�-rr�� r"t��r r;�r r���t�, - C s� � strr.�r�r�t3 rem(.✓,�� r r 1 PROJECT: BY: r LOCATION: !" CHECKED: SHEET ✓ / / /J!'ft G" /7r�✓ 21 T S rQ CONSULTING ENGINEERS CLIENT: � DATE: - 9'' 71 875 - 140TH AVE. N.E. • SUITE 201 BELLEVUE • WA 98005 (206)747-3592 JOB NO. ' KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TABLE 3.5.211 SCS WLSTLRN NVASIIINGTON RUNOFF CURVE NUMBERS SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS (Published by SCS in 1982) Runoff curve numbers for selected agricultural, suburban and urban land use for Type 1A rainfall distribution, 24-hour storm duration. CURVE NUMBERS BY HYDROLOGIC SOIL GROUP ' LAND USE DESCRIPTION A B C D Cultivated land(1): winter condition 86 91 94 95 Mountain open areas: low growing brush and grasslands 74 82 89 92 Meadow or pasture: 65 78 85 89 Wood or forest land: undisturbed or older second growth 42 64 76 81 Wood or forest land: young second growth or brush 55 72 81 86 Orchard: with cover crop 81 88 92 94 Open spaces, lawns, parks, golf courses, cemeteries, landscaping. good condition: grass cover on 75% or more of the area 68 80 86 90 fair condition: grass cover on 50% ' to 75% of the area 77 85 90 92 Gravel roads and parking lots 76 85 89 91 Dirt roads and parking lots 72 82 87 89 Impervious surfaces, pavement, roofs, etc. 98 98 98 98 ' Open water bodies: lakes, wetlands, ponds, etc. 100 100 100 100 Single Family Residential (2) Dwelling Unit/Gross Acre % Impervious (3) 1.0 DU/GA 15 Separate curve number 1.5 DU/GA 20 shall be selected 2.0 DU/GA 25 for pervious and 2.5 DU/GA 30 impervious portion 3.0 DU/GA 34 of the site or basin ' 3.5 DU/GA 38 4.0 DU/GA 42 4.5 DU/GA 46 5.0 DU/GA 48 5.5 DU/GA 50 6.0 DU/GA 52 6.5 DU/GA 54 7.0 DU/GA 56 ' Planned unit developments, % impervious condominiums, apartments, must be computed commercial business and industrial areas. (1) For a more detailed description of agricultural land use curve numbers refer to National Engineering Handbook, Section 4, Hydrology, Chapter 9, August 1972. ' (2) Assumes roof and driveway runoff is directed into street/storm system. (3) The remaining pervious areas (lawn) are considered to be in good condition for these curve numbers. 3.5.2-3 11/92 71 PROJECT: BY: AijCa LOCATION:xrzs CHECKED: SHEET CONSULTING ENGINEERS CLIENT: X�e,-/ DATE: 875 - 140TH AVE. N.E. - SUITE 201 BELLEVUE WA 98005 (206)747-3592 JOB NO. ........... .............. �4 Z4 ............... ........... ................... .............. .......... ........... ............. 4z ........... ................. N. ........... .......................... ...... ..... ......... ................... ...... .......... .......... ... ....... N, ............. ..... . ......... 493.27'(CALC)�04.15 (PLAT) N. :3 C7 ........... 2 a:.......... ........... .......... w ............L J N. '?................ z -IN IN ................... y z i if N L ., Lu ................. .................... L �L NN ........... ........... -j .............. .............. IN . ........................�4 Ni"a z N, IN, N\ -4 ................ 32 0 .......... ..............J iV N, IN, y .. ............................I No I., ........................ ..................... V ............ N .......... N\ LLJ ......... . ........ .................................................... N. N.. .. .........I IN, N\ IN ........................... IN, .......... ULJ .......... .............. N, 0 ,IN, ...... ........ • ........... i 100!•�V-............ 40'HAUL ROAD EASEMENT z es Lu • .......... w En............. ... .......... ZILu Lu cr 0 .................. ........... • % uj 93.47',(CALC) 12 T) 3 7- NOO-55-48-e I, ........... - - - - - - - - - -- - - - 01L71ES EASEMENTS :!p Ur 12NTAN� --K� LL- -t- — Nj 0 IN. ASEMENTS UTILITIES E Lu ASPHALT PARKJNC AREA Z, "N LEGEND J. EXISTING FL13V IN, ARE 4 %\ , PREIPERTY LINE I AT 9 IN, 1 1 C, 0 EASEMENT • 7 z DATE REMION NOO'55 ............ ........................- 48'E 51,80' -c 3 .......................................... EDGE OF CURB —Na 48 EX11ITING ME OF PAVEMENT IN, LAT) :4 ............ ORICINAI.BENCH MAIM: KC-F-10,BRASS OfSt IN SIDEWALK AT cXMIED OAS VERTICAL DATVM:CITY OF RENTON(NAVO 86) k TH ELEV.-121.30 ]MT.S.W.43M BY AND TALBOT ROAD TBU#1 TOP REBAR AND CAP At S.W.PROPERTY CORNER ELEV.-209.67 tEX19WY BENCH HAW Tom#z PK mAiL 2i't sw OF THE N.E.PRoPERry CORNER EXISTDC R=RT ELEV.1 68.50 LEG DESCRIPTION EXISTING QQNDITI NS AL EXISTING CATCH BASIN LOTS 2.3 AND 4 OF CITY OF RENTON 940RT PLAT MO.074-ft Sr" IN RECORDED UNDER RECORDING NO.8612OL49006.RECORDS OF IONG —0 JOB NO: 95071 EXISTD&HAAHEILE COUNTY.WASHINCTON. I L SANITARY SEWER sct. I I DATE: 07.17.95 SITUATE IN THE COUNTY OF PQNG�STATE OF WASHIN". TELEPHDc JIM DRAWN: MG P: PORTION SE 1/4. NE 1/4 SECTION 31, ZICKID., IT 7; "IrpHame WA43LE TOWNSHIP 23N, RANGE 5E W.N. /(LALC) 55 E z BASIS OF BEARING IV SANITARY SEWER EASEMENT EXISTING PAVX LW RECORD OF SURVEY RECORDED IN SEE SPECIA-EXCEPT04 NO.15 SHEET NO: R%f DATA BOOK 33 OF SURVEYS AT PACE 224 PUBUC UTILITIES EASEW-1-S DELTA RECORDS OF KING COUNTY WASHINGTON CL Cu :;39-35-14(39-35-44 FBECORO)P; -RC-3918 7(.395.96 RECORD) IN NnR.W ""us.57Z99 C-1 EXISTING WATER METER ROD(CHECK SAX 1 ............ .} ........................ ...., tt<, ,. : ............ ...... .... - h / f .................... ....... ..... .... , 493.27 CALC9 15 ` - '"\ ! _ @ PLAT ......a •.,\ ,\\._\\; \\ ............ _ _ \ R - _ .....:.::. , o ..... La ..... - �.2 \ LU a. y i ; S { s rJ ril ,� \ 1 _ b Li 1 1 �1 .i f " ' a F t � I t r, ............t 'hf'"•x 41 i • ROCK CHECK DAU, F .. i Y2 r,..................... a ... ... .`..i,. /,,. i<'S .. \wST.BETWEEN DAAr9 1.f i ....... .... i i \ U 1 ` a.. i i f r 1 \ \ ........ .. i I ................... .. -\ s € cONSTRUCTIG�4 ENTRANCE. PROPOSE(PARKING LOT. \ ` / W .. ........ .... � pETNL st �SPALLS \ U , Lu „ •_(SEE '\ \i. u ... `\. — ` �'J ♦ / \ \` ........ .... ( T`7 \ ,\ a- „ I 1. NI. \ 51�Ilwt // s: ,t R „ J \ J. :fi2-27 (� ®GR 1 \\ S ST' \ e - - i. 1 \LUSTS,GF CLEARING \ MY FILTER FE� I - / \•'-.•.._ '�., Q J. IPi 1 \ ROCK GEac DAM ` �, \ \. : rn ,[� I (DIs t3E ) Q 1 ao ;`_..... 40'HAUL`Rj AD EASEMENT . F Z , , , , , , , -1. \, \ •` , , , � G9• :'fr 1l'7':,..r.f: r� \ \ � _ y � Z Q SEDILIE1tr TRAv \ I / f3I Q W DEPTH Z � z CD tiT cr n 393.Z7 /�C 7 ui _ .+: 1 , , , aS .: ..,..:...:...a>. ,:,...:-•-�. ,.. C' ......... . ` ... LJL _ tY JDIN ASEMENTSn unLRIEs E _ r 3< ., :'. o SEE SPECIAL II i \ v �.<�a" — � L� ' — — — — — — — ExcEVTgn No.T5 ILLI ASPHALT PARKING AREA PUBLIC UTILITIES EASEMENTS LEGEND -\ �' -�- PRDPOSEO Rav I 1 [\ �'. %•, PIRDPERT7 LO/E F� I I I I I l\ l <\\ C cLSE1F,Nr ! 1 ._._._................................ �00'S5'48 E ExiSrtNG EDGE rK vAVDENT 1 \'` ��\ NOO'55'48'E 51.80' 1 ,..'", :. i:x7Y=<3s>:a:: i,• -...;..:.,;\ ~.yy t ......_...................................... am OF CURBl.r. 5•- CITY RENTOi A - - ........,,..,.,.. ............. .:..-.,.....,.:...... < e DATE REVISION .... •�, _...,, EXTRIIIED QlR9 ORIGINAL BENCH•MAIM:�-F-10.BRASS DISC IN 90EWALK AT �. ROAD 1 \ •_, _� _ _ — INT.sw.43R0 Sr.AN D TALBOT tag .:;n SOUTH ELEv..121.70 L_ \/ .,_.. ._. \ ' TEIPDURr 6EACII MARK TAM/I TOP REBAR AND CAP AT S.W.PROPERTY CORNER 1 \ `• PKELE NIL IY4 OF THE N.E.PROPERTY COWER 7BM(1 PK L.50 , , .......,. a`t' EXISTING RDD�ftr 11EV.,86.50 SI / DIMENTATION 0 \. LEGAL DESOIPTIOn C NTFtOI\PLAN. \TEMPORARY ERRb OW SL \ s�:..:°^„ _... .•: ......... ....... �.--...... Exmuc CATCH P41M � PNOPO ED CONDITIONS. ' Lon Z 3 AND 4 a CITY OF RFTtTOn stair PLAT no.074- 1 L STORK[BRAIN RECORDED UNDER RECORDING NO.8612049000.RECORDS OF KING 20 1 0 4d so JOB N0: 95071 /\.........._........ ........... EXISTING 140CLE COUNTY,WASHINGTON. 1-20' \ I 4 I ,: t SANITARY SEVER SITUATE w THE COUNTY a'TONG STATE OF WASHINGTON. ecate 1 1 11 Feet \\ \ DATE: 07.1795 ...a TELEP CNE RISER \ DRAWN: MG P \ 1 PORTION SE 1/4, NE 1/4 SECTION 31, 1 \ CHECKED: ST _. TIIFPIOE NAndLE TOWNSHIP 23N, RANGE 5E W.M. 1 1 1 IO'SANITARY$EY,fR EASEMENT \ ' BASIS OF BEARING ` Ex[STtNG PARNtrfi LIGM RECORD OF SURVEY RECORDED IN I 1 1 SEE SPECIAL ExcEPTIGn N0.t1 \ \ SHEET N0: CL N DATA �; BOOK 33 OF SURVEYS AT PACE 224 PUBLIC ununes EASEMENTS \ \ 1 SIGN RECORDS OF KING COUNTY WASHINGTON LA 39-J�14(38-35-44"PECORD)P \ \ ^- 1.67(395.96 RECORD) : •'�• FIRRE NYORANT v 17Z98 fj) EXISTINK WATER METER g to R DIX CIEOI BAN a 1 ' 112 5 1 � 1 r. // 5'Hd/LGdzt� �rcC Xyi%r�'T:1J 1-..UJ 77/eW Siloo-( � c� � �/�� — ✓��- ✓� /'��©cam 1 `/ -- �� 1��•o � v ..,... �•2 FPS i 1 1 1 PROJECT: (,, / rl !C BY. LOCATION: JQ CHECKED: SHEET ' CLIENT: DATE: CONSULTING ENGINEERS T S 9�d7� 1 875 - 140TH AVE. N.E. SUITE 201 • BELLEVUE • WA 98005 • (208)747-3592 JOB NO. -2- 9 klYeVirs ' L.� 2/'t. %1/� ��fit' 1�r'>C!('..� �--?:� �.' '.�,> t.F��'f l�. ' TNT 'TYi12GC-TE� DISC-►I'�!r_'GG ,J?��.C;,�f�'C �i��S 112;11D 101-rl-1 771Z---- 7,7 t `�cam. r-'� c.� t�ou T�f��' �-� ��i�,�-�r cf� ��T ��r A., PROJECT: Z07- BY: r3 LOCATION: CHECKED: SHEET CONSULTING ENGINEERS CLIENT: 4OA(-211 Ir- DATE: 875 - 140TH AVE. N.E. SUITE 201 - BELLEVUE WA 98005 (206)747-3592 JOB NO. IPECIFY STORM OPTION: i .C.S . TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ (YEAR) , DURATION (HOUR) , PRECIP (INCHES) , 24 , 2 ----------------------------- -- --- --------- -------------------------- ******************** S . C. S . TYPE-lA DISTRIBUTION ******************** ******** 2-YEAR 24-HOUR STORM **** 2 . 00" TOTAL PRECIP. ********* -------------- ------ ------- --------------- ---------- ------- --------- -- ENTER: A(PERV) , CN (PERV) , A(IMPERV) , CN (IMPERV) , TC FOR BASIN NO. 1 1 . 61, 85, 0 , 98 , 23 . 6 DATA PRINT-OUT: ' AREA(ACRES) PERVIOUS IMPERVIOUS TC (MINUTES) A CN A CN 1 . 6 1 . 6 85 . 0 . 0 98 . 0 23 . 6 PEAK-Q (CFS) T-PEAK (HRS) VOL (CU-FT) 20 7 . 83 4624 NTER [d: ] [path] filename [ . ext] FOR STORAGE OF COMPUTED HYDROGRAPH: PMC2X.HYD SPECIFY STORM OPTION: I . C. S . TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ (YEAR) , DURATION (HOUR) , PRECIP (INCHES) 0, 24 , 2 . 9 ------------------ ------- ---------- -- -- ------------- ------------- -- -- ******************** S .C. S . TYPE-lA DISTRIBUTION ******************** ******** 10-YEAR 24-HOUR STORM **** 2 . 90" TOTAL PRECIP. ********* ------------------- --- -- ---- ------------------ ----------- ---- --------- NTER: A(PERV) , CN (PERV) , A(IMPERV) , CN (IMPERV) , TC FOR BASIN NO. 1 . 61, 85, 0 , 98, 23 . E DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC (MINUTES) A CN A CN ' 1 . 6 1 . 6 85 . 0 . 0 98 . 0 23 . 6 PEAK-Q (CFS) T-PEAK (HRS) VOL (CU-FT) 45 7 . 83 8756 �NTER [d: ] [path] f i lename [ .ext] FOR STORAGE OF COMPUTED HYDROGRAPH: PMC10X.HYD SPECIFY STORM OPTION: O . C. S . TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ (YEAR) , DURATION (HOUR) , PRECIP (INCHES) 00, 24 , 3 . 9 ------------------ ------- -- ------ -- -- ----- ------------------------ --- ******************** S . C. S . TYPE-lA DISTRIBUTION ******************** ******** 100-YEAR 24-HOUR STORM **** 3 . 90" TOTAL PRECIP . ********* --------------- --- ----- -------------- ----- -- -------------------------- NTER: A(PERV) , CN (PERV) , A(IMPERV) , CN (IMPERV) , TC FOR BASIN NO. 1 . 61, 85, 0 , 98 , 23 . E DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC (MINUTES) A CN A CN ' 1 . 6 1 . 6 85 . 0 . 0 98 . 0 23 . 6 PEAK-Q (CFS) T-PEAK (HRS) VOL (CU-FT) 75 7 . 83 13762 �NTER [d: ] [path] f i lename [ . ext] FOR STORAGE OF COMPUTED HYDROGRAPH: PMC100X.HYD 1 SPECIFY STORM OPTION: I. C.S . TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ (YEAR) , DURATION (HOUR) , PRECIP (INCHES) t 24 , 2 ---------------------- --- --- --------------------- -- ------- ----- - ---- ******************** S . C. S . TYPE-lA DISTRIBUTION ******************** ******** 2-YEAR 24-HOUR STORM **** 2 . 00" TOTAL PRECIP . ********* ----------------------- -- ---- -- -------------------------------- - ---- - - �NTER: A(PERV) , CN (PERV) , A(IMPERV) , CN (IMPERV) , TC FOR BASIN NO . 1 81, 88, . 8 , 98 , 3 . 05 DATA PRINT-OUT: ' AREA(ACRES) PERVIOUS IMPERVIOUS TC (MINUTES) A CN A CN 1 . 6 . 8 88 . 0 . 8 98 . 0 3 . 0 PEAK-Q (CFS) T-PEAK (HRS) VOL (CU-FT) 65 7 . 67 7993 �NTER [d: ] [path] filename [ . ext] FOR STORAGE OF COMPUTED HYDROGRAPH: PMC2D.HYD SPECIFY STORM OPTION: I .C. S . TYPE-lA RAINFALL DISTRIBUTION ENTER: FREQ (YEAR) , DURATION (HOUR) , PRECIP (INCHES) 0, 24 , 2 . 9 ------------------------------------- ----- ----------------------- - -- - ******************** S . C. S . TYPE-lA DISTRIBUTION ******************** 10-YEAR 24-HOUR STORM **** 2 . 90" TOTAL PRECIP . ********* ---------- ---- ---- --- ------ ----- - --- -------- - - ------- -- --------------- �NTER: A(PERV) , CN (PERV) , A(IMPERV) , CN (IMPERV) , TC FOR BASIN NO. 1 81, 88 , . 8 , 98 , 3 . 05 DATA PRINT-OUT: AREA(ACRES) PERVIOUS IMPERVIOUS TC (MINUTES) A CN A CN ' 1 . 6 . 8 88 . 0 . 8 98 . 0 3 . 0 PEAK-Q (CFS) T-PEAK (HRS) VOL (CU-FT) 1 . 07 7 . 67 12840 �NTER [d: ] [path] f ilename [ . ext] FOR STORAGE OF COMPUTED HYDROGRAPH: PMC10D.HYD 1 1 SPECIFY STORM OPTION: I S .C.S . TYPE-lA RAINFALL DISTRIBUTION NTER: FREQ (YEAR) , DURATION (HOUR) , PRECIP (INCHES) 00 , 24 , 3 . 9 --------------- -- ------ -------- ----- -------------------------------- - ******************** S . C. S . TYPE-lA DISTRIBUTION ******************** 100-YEAR 24-HOUR STORM **** 3 . 90" TOTAL PRECIP . ********* --------------------- ------ ----- ------- - --- --------------------------- r TER: A(PERV) , CN (PERV) , A (IMPERV) , CN (IMPERV) , TC FOR BASIN NO.1, 88 , . 8, 98 , 3 . 05 fTA PRINT-OUT : AREA(ACRES) PERVIOUS IMPERVIOUS TC (MINUTES) A CN A CN 1 . 6 . 8 88 . 0 . 8 98 . 0 3 . 0 PEAK-Q (CFS) T-PEAK (HRS) VOL (CU-FT) 1 . 55 7 . 67 18401 INTER [d: ] [P ath] f i lename [ . ext] FOR STORAGE OF COMPUTED HYDROGRAPH: �MC100D.HYD FMARY OF INPUT ITEMS ') TYPE OF FACILITY: POND (3 . 0 : 1 SIDE SLOPES) STORAGE DEPTH (ft) : 4 . 00 3) VERTICAL PERMEABILITY (min/in) : . 00 �) PRIMARY DESIGN HYDROGRAPH FILENAME : PMC100D.HYD PRIMARY RELEASE RATE (cfs) : . 75 �) NUMBER OF TEST HYDROGRAPHS : 3 TEST HYD 1 FILENAME : PMC2D.HYD TARGET RELEASE (cfs) : . 20 TEST HYD 2 FILENAME : PMC10D.HYD TARGET RELEASE (cfs) : . 45 TEST HYD 3 FILENAME : PMC100D.HYD TARGET RELEASE (cfs) : . 75 7) NUMBER-OF-ORIFICES, RISER-HEAD (ft) , RISER-DIAM (in) : 3 , 4 . 00 , 12 r) ITERATION DISPLAY: YES TER ITEM NUMBER TO BE REVISED (ENTER ZERO IF NO REVISIONS ARE REQUIRED) : INITIAL STORAGE VALUE FOR ITERATION PURPOSES : 6276 CU-FT IOTTOM ORIFICE : ENTER Q-MAX (cfs) 0 . 25 IA. = 2 . 15 INCHES IDDLE ORIFICE : ENTER Q-MAX (cfs) , HEIGHT (ft) . 3 , 2 . 49 IA. = 3 . 00 INCHES OP ORIFICE : ENTER HEIGHT (ft) . 32 DIA. = 2 . 99 INCHES ITERATION COMPUTATION BEGINS . . . RIAL BOTTOM-AREA STOR-AVAIL STOR-USED PK-STAGE PK-OUTFLOW 1 702 .4 6275 4185 3 . 11 . 41 2 529 . 8 5230 3833 3 . 33 . 46 3 419 . 6 4532 3548 3 . 48 . 55 4 345 . 1 4040 3327 3 . 60 . 62 5 293 . 1 3683 3157 3 . 68 . 65 6 255 . 9 3420 3035 3 . 75 . 67 7 229 .4 3228 2945 3 . 81 . 69 8 210 .4 3086 2866 3 . 85 . 70 9 195 . 9 2976 2802 3 . 88 . 71 10 184 . 6 2889 2751 3 . 90 . 72 I11 175 . 7 2820 2710 3 . 92 . 72 12 168 . 7 2765 2676 3 . 93 . 73 13 163 . 2 2721 2649 3 . 94 . 73 1 14 158 . 7 2685 2627 3 . 95 . 74 15 155 . 1 2656 2609 3 . 96 . 74 16 152 . 2 2632 2594 3 . 97 . 74 I17 149 . 8 2613 2582 3 . 98 . 74 t8 147 . 9 2597 2572 3 . 98 . 74 19 146 . 3 2585 2564 3 . 98 . 74 145 . 1 2574 2557 3 . 99 . 75 flo 144 . 0 2566 2552 3 . 99 . 75 22 143 . 2 2559 2547 3 . 99 . 75 23 142 . 5 2553 2543 3 . 99 . 75 t4 141 . 9 2548 2540 3 . 99 . 75 5 141 . 4 2544 2538 3 . 99 . 75 26 141 . 0 2541 2536 4 . 00 . 75 17 140 . 7 2538 2534 4 . 00 . 75 8 140 . 5 2536 2533 4 . 00 . 75 29 140 . 3 2534 2532 4 . 00 . 75 30 140 . 1 2533 2531 4 . 00 . 75 tRFORMANCE : INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE STORAGE DESIGN HYD : 1 . 55 . 75 . 75 4 . 00 2531 LEST HYD 1 : . 65 . 20 . 20 2 . 49 1000 EST HYD 2 : 1 . 07 . 45 . 45 3 . 32 1730 TEST HYD 3 : 1 . 55 . 75 . 75 4 . 00 2530 IPECIFY: D - DOCUMENT, R - REVISE, A - ADJUST ORIF, E - ENLARGE, S - STOP E FLARGEMENT OPTION: ALLOWS FOR INCREASING STORAGE AT A SPECIFIED STAGE HEIGHT, TO PROVIDE A FACTOR OF SAFETY. TER: STORAGE-INCREASE (o) , STAGE-HEIGHT (ft) 0, 4 FRFORMANCE : INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE STORAGE ESIGN HYD: 1 . 55 . 75 . 68 3 . 79 2978 TEST HYD 1 : . 65 . 20 . 18 2 . 18 1110 ,TEST HYD 2 : 1 . 07 .45 . 40 3 . 05 1990 TEST HYD 3 : 1 . 55 . 75 . 68 3 . 79 2970 SPECIFY: D - DOCUMENT, R - REVISE, A - ADJUST ORIF, E - ENLARGE, S - STOP PERFORMANCE : INFLOW TARGET-OUTFLOW ACTUAL-OUTFLOW PK-STAGE STORAGE 'DESIGN HYD : 1 . 55 . 75 . 68 3 . 79 2978 TEST HYD 1 : . 65 . 20 . 18 2 . 18 1110 TEST HYD 2 : 1 . 07 . 45 .40 3 . 05 1990 ,TEST HYD 3 : 1 . 55 . 75 . 68 3 . 79 2970 STRUCTURE DATA: R/D-POND (3 . 0 : 1 SIDE SLOPES) 'ISER-HEAD POND-BOTTOM-AREA TOP-AREA(@l' F.B. ) STOR-DEPTH STORAGE-VOLUME 4 . 00 FT 238 . 4 SQ-FT 2120 . 9 SQ-FT 4 . 00 FT 3293 CU-FT ,RIPLE ORIFICE RESTRICTOR: DIA(INCHES) HT (FEET) Q-MAX (CFS) BOTTOM ORIFICE : 2 . 15 . 00 . 250 MIDDLE ORIFICE : 3 . 00 2 . 49 . 300 TOP ORIFICE : 2 . 99 3 . 32 . 200 ROUTING DATA: ITAGE (FT) DISCHARGE (CFS) STORAGE (CU-FT) PERM-AREA(SQ-FT) . 00 . 00 . 0 . 0 . 40 . 08 111 . 8 . 0 . 80 . 11 259 . 7 . 0 1 . 20 . 14 448 . 3 . 0 ' 1 . 60 . 16 682 . 1 . 0 2 . 00 . 18 965 . 8 . 0 2 .40 . 19 1303 . 9 . 0 2 . 49 . 20 1388 . 0 . 0 2 . 80 . 35 1701 . 2 . 0 3 . 20 . 43 2162 . 1 . 0 3 . 32 . 45 2313 . 5 . 0 ' 3 . 60 . 62 2691 . 4 . 0 4 . 00 . 75 3293 . 6 . 0 4 . 10 1 . 09 3456 . 0 . 0 ' 4 . 20 1 . 67 3623 . 4 . 0 4 . 30 2 . 43 3795 . 8 . 0 4 .40 3 . 24 3973 . 3 . 0 4 . 50 3 . 55 4155 . 8 . 0 LERAGE VERTICAL PERMEABILITY: . 0 MINUTES/INCH IECIFY: F - FILE, N - NEWJOB, P - PRINT IF/OF, R - REVISE, S - STOP r 8� 0E-iG7.e,17 ' CHANNEL FLOW BIOFILTRATION CONVEYANCE BOTTOM WIDTH(B)ft 7 7 ' FLOW DEPTH(H)FT 0.33 0.17 ROUGHNESS(N) 0.35 0.08 SLOPE(S)FT/FT 0.02 0.0748 AREA(A) 2.6367 1.2767 WETTED PERIMETER(P)FT 9.087103256 8.075174404 ' RADIUS(R)FT 0.290158472 0.158101848 ' VOLUME(Q)CFS 0.692882452 1.889834154 (2YR 24HR) (100YR 2411R) VELOCITY(V)FPS 0.262783954 1.480249201 ATION . 00 : INVERT= 154 . 00 FT EC=1 . 15 Q-RATIO=1 . 00 ROSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES ' LEFT (FT) STAGE (FT) N-FACTOR * RIGHT (FT) STAGE (FT) N-FACTOR 3 . 50 . 00 . 080 * 3 . 50 . 00 . 080 ' 8 . 00 1 . 50 . 080 * 8 . 00 1 . 50 . 080 Q (CFS) Yl (FT) WS ELEV. * YC-IN YN-IN Q-TW TW-HT N-Yl A-Yl WP-Yl V-Yl ****************************************************************************** . 65 . 10 154 . 10 * . 07 . 10 . 00 . 00 . 080 . 73 7 . 63 . 89 . 80 . 11 154 . 11 * . 08 . 11 . 00 . 00 . 080 . 81 7 . 70 . 99 . 95 . 12 154 . 12 * . 09 . 12 . 00 . 00 . 080 . 88 7 . 76 1 . 08 1 . 10 . 13 154 . 13 * . 10 . 13 . 00 . 00 . 080 . 96 7 . 82 1 . 14 1 . 25 . 14 154 . 14 * . 11 . 14 . 00 . 00 . 080 1 . 04 7 . 89 1 . 20 1 . 40 . 15 154 . 15 * . 12 . 15 . 00 . 00 . 080 1 . 12 7 . 95 1 . 25 ' 1 . 55 . 16 154 . 16 * . 12 . 16 . 00 . 00 . 080 1 . 20 8 . 01 1 . 30 ***REACH NO. 1 : LENGTH= 254 . 00 FT AVG.GRADE= 7 . 48% **** STATION 254 . 00 : INVERT= 173 . 00 FT EC=1 . 15 Q-RATIO=1 . 00 TOSS-SECTION DATA: DIST/STAGE IS MEASURED FROM INVERT; N-FAC IS MEASURED BETWEEN STAGES ' LEFT (FT) STAGE (FT) N-FACTOR * RIGHT (FT) STAGE (FT) N-FACTOR 3 . 50 . 00 . 080 * 3 . 50 . 00 . 080 8 . 00 1 . 50 . 080 * 8 . 00 1 . 50 . 080 'Q (CFS) Y1 (FT) WS ELEV. * YC-IN YN-IN YC-OT YN-OT N-Yl A-Y1 WP-Yl V-Y1 ******************************************************************************* ' 32 . 06 173 . 06 * . 03 . 00 . 05 . 06 . 080 . 43 7 . 38 . 75 .40 . 07 173 . 07 * . 04 . 00 . 05 . 07 . 080 . 50 7 . 44 . 79 .47 . 08 173 . 08 * . 04 . 00 . 06 . 08 . 080 . 58 7 . 51 . 82 ' 55 . 09 173 . 09 * . 04 . 00 . 06 . 09 . 080 . 65 7 . 57 . 84 . 62 . 09 173 . 09 * . 05 . 00 . 07 . 09 . 080 . 65 7 . 57 . 96 . 70 . 10 173 . 10 * . 05 . 00 . 08 . 10 . 080 . 73 7 . 63 . 96 77 . 10 173 . 10 * 05 . 00 . 08 . 10 . 080 . 73 7 . 63 1 . 06 �TE : WATER DEPTH INFORMATION FOR THIS LAST CROSS-SECTION WAS COMPUTED ASSUMING APPROACH VELOCITIES GREATER THAN OR EQUAL TO CROSS-SECTIONAL VELOCITIES . ' IF NOT THE CASE, WATER DEPTHS CAN BE ADJUSTED BY SPECIFYING, A - ADJUST. SPECIFY: F - FILE, A - ADJUST, P - PRINT R/D, N - NEWJOB, S - STOP OUTING DATA: tTAGE (FT) DISCHARGE (CFS) STORAGE (CU-FT) PERM-AREA(SQ-FT) . 00 . 00 . 0 . 0 . 10 . 65 147 . 4 1906 . 5 ' 11 . 80 166 . 5 1922 . 6 . 12 . 95 185 . 7 1938 . 6 . 13 1 . 10 205 . 1 1954 . 7 ' 14 1 . 25 215 . 0 1962 . 7 r . 15 1 . 40 234 . 6 1978 . 8 . 16 1 . 55 244 . 7 1986 . 8 FECIFY: F - FILE, A - ADJUST, P - PRINT R/D, N - NEWJOB, S - STOP r r r r r r r r r r r r r r r r r ' LEVEL 1 OFFSITE ANALYSIS ' UPSTREAM The upstream property located to the east, slopes towards the project site; however, the existing drainage ditch along the est property line intercepts the runoff from upstream areas effectively and diverts the flow north to an existing catch basin and a drainage system that conveys the drainage via a series of 18" to 30" concrete pipes across Carr Road, Talbot Road through Valley Hospital parking to an existing drainage ditch called Panther Creek. This drainage ultimately reaches an existing wetland. DOWNSTREAM The discharge from the detention pond is through a control structure to an existing inlet at the north-west confer of the property. This inlet shown on the Paving, Grading and Drainage Plan is part of a drainage system that consists of an ' 18" concrete pipe at 7.7% slope along the access road. Very sketchy information is available regarding the actual route this drainage system takes, west along Carr road and North along Talbot road to Panther Creek drainage system. The city staff believes this downstream system consists of a series ' of 18" to 30" concrete pipes leading to the drainage system known as Panther Creek drainage system which ultimately ends in an existing wetland. EXISTING DRAINAGE PROBLEMS: During a discussion with Mr. Mike Dotson at the City of Renton Storrn Drainage Division it was verified that there are no known drainage problems ' concerning the downstream drainage system on record. ��—.SP 213- 78 I I171.17 rr. Q /--) C—�-7 S—' I'}�, �l o? PI L ^ 32 Q }w/ �6 �J '❑ J r,l /. `t'� /l•� �l !: � �_: :1~ I << I Pc l�4_,❑ �j% i'��c' �O�AL. � ! F r4 I C S. 17 7 TH S T. P '9 •� ! !•� ,t /.' o -" � ,'ter I c5 99 571 I 66.13 S4 .11 ° i 311.7 cc 77/D W 1 �y s I n o cp / T 12 Ronald 5_II r •ci � '\ f.. 31 W. ScOtl 11 Y''l = iC6 5 ./ 14 CYc \ _ \� ` ;�L�� ' ^ 1✓� IN'I 3.28 AC.'�i !i 4 15 �' 21 g' 26 s ? o OI �'m ! !' 7 R 75'b 24 ,r,,7 oJ� I J\,5 \�j-��,( O `� 21;.0 23 C❑\ :oz °s.o 7 2 I!' 7�9 '? '-,-s f c�J 4�4�y_5462 �N y r o x 18 = ..rts' _... . .3o 00 �'1'St/ / 45 W 44 �' 43 - Q cmS.P. 056 R j 1276 S F. I2820437 2 ;V (2) (2) Gp �779/S 25 ors /,'fir/c . I 1o1I5m i Z Z2'A�c `s '*--{ 2.`: Ac. 10 . 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