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HomeMy WebLinkAboutSWP272337(1) • ............»......:.:..:.>...:..:.>...:..:.>...:. : :. ' ...................................... ............................................................. .......... ..... ......... ....... .......... .... ............ ::' *........... .......................... ............. ........................... ........................................................ ........ .... 'X ............... ....... ................ ...... .. ...... < > > >.. ..............R ::::: TA:RM><::: A . :> < > L. . . . tV > >. ::::>::::>::::>:<:>::::>::::>::>::::>::::>:::::>::::::>::::>::::>::><:»>::>::>::>::>::;::>::>::>::>::>::>::>:<:>:: xx ' ' I '` <>::i::`:i :i::::::i# ::;:j':::::::is%:i:::::Y:::%i:::%:::::>:'... .;s: 4'.. .. ................. 45'.................................................................... ::::i ::i:::::2::i::::::::::i::i::::::.. ::i::::::i::::is :1 :::::::: ::::::::::::: :::::::::::"' ....:::: ::i::::: ::'::::i::::::::i::::: :::::i::::::::i:::: . a 9 ' �I 1 DeV rIT1 OF RIENTt�I�►NG OUR JOB NO. 6045 U MARCH 12, 1997 3 �O9 q 2=8148 O,o FQI,0T.rEA� ASS/pNAI ENG� Prepared By: EXPIRES 4/ BARGHAUSEN CONSULTING ENGINEERS, INC. 18215 72ND AVENUE SOUTH KENT, WASHINGTON 98032 (206) 251 -6222 m�GH%�2 o CIVIL ENGINEERING, LAND PLANNING, SURVEYING, ENVIRONMENTAL SERVICES �b dam" • TABLE OF CONTENTS 1.0 INTRODUCTION/GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 EXISTING SITE CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 DOWNSTREAM DRAINAGE ANALYSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 ON-SITE DRAINAGE CONSIDERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.0 STORM DRAINAGE DETENTION CALCULATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.0 RESOURCE REVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A. ASSESSOR'S ' MAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B. FLOODPLAIN/FLOODWAY FEMA MAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C. WETLAND INVENTORY MAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D. SENSITIVE AREA FOLIOS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • E. SOILS SURVEY MAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • 1.0 INTRODUCTION/GENERAL INFORMATION The proposed nine-lot short plat is located in Section 19, Township 23, Range 5 East, Willamette Meridian, in the City of Renton, Washington. The site is bound by Lind Avenue S.W. to the west, S.W. 19th Street to the south, East Valley Road to the east, and existing office buildings to the north. The rectangular site is approximately 14.5 acres. 2.0 EXISTING SITE CONDITIONS The King County Soil Classification Guide shows the site to have a mixture of soil types. The survey indicates the site consists of the Puyallup soil group, which is a hydrologic Group B, and an urban soil group, which is a variable hydrologic group. However, this survey was done prior to the site being filled with several feet of imported material. Our site investigation reveals that the on-site soils probably are a hydrologic Group C. The site is almost fully grassed and contains small areas of light brush, but no significant trees. The topography is very flat. Some small depressions exist due to previous inconsistent fill placement. The site sits higher relative to its surroundings and, therefore, receives no off-site drainage. 3.0 DOWNSTREAM DRAINAGE ANALYSIS • Storm drainage runoff from the project sheetflows from north to south and is collected at two low points along the south property line by two existing catch basins. These two catch basins are located behind the road improvement and collect runoff from the existing site. The catch basins are protected by a silt fence buffer and discharge runoff to the existing 60-inch diameter storm tightline system along S.W. 19th Street. The existing 60-inch diameter tightline system along S.W. 19th Street travels westerly toward the intersection of S.W. 19th Street and Lind Avenue S.W. (87th Avenue South). From the intersection of S.W. 19th Street and Lind Avenue S.W., the 60-inch storm drain travels due west approximately 1,100 lineal feet in a 60-inch reinforced concrete pipe system. It discharges at this point into a well defined 6-to 10-foot deep vegetated ditch that appears to be approximately 5 feet wide with 2 to 1 side slopes. At a point approximately 200 feet west, the flow enters a 60-inch corrugated metal pipe which conveys the drainage due westward approximately 100 feet into Springbrook Creek where it is discharged. 4.0 ON-SITE DRAINAGE CONSIDERATIONS The proposed short plat will contain one drainage/detention system for the entire project. Drainage from the site will be discharged into the existing wetland across S.W. 19th Street to the south of the site, which ultimately flows into the previously mentioned 60-inch storm drainage system in S.W. 19th Street. The wetland will be used for peak rate runoff control. In addition, a wet/detention vault located on the south property line of the site will also be used for some detention. This system is • described in greater detail in the following paragraphs. All site storm drainage detention and water quality systems will meet City code and be in accordance with City standard systems or equivalent systems. 6045.001 [KL/es] • Storm drainage construction for the first phase of the project will consist of the construction of the wet/detention vault and outfall, as well as the storm drainage conveyance system which will provide stubs to each individual lot. When the individual lots are developed, their storm drainage systems can then tie into the provided stubs. Water quality for the entire project will be provided in the wet/detention vault located along the south property line of the site. The vault is designed using the February 1996 draft of the King County Surface Water Design Manual, which is a method of analysis based on computer modeling using the King County Runoff Time Series (KCRTS) model. The City of Renton requires the wetpond to be 1.5 to 2 times the design surface area and volume as calculated using the 1990 KCSWDM Design Standards if a biofiltration swale does not precede it. Using the KCRTS method of design, the vault is approximately 1.8 times the surface area and 2.7 times the volume requirements of the 1990 KCSWDM. The wetpond design calculations are contained later in this report. The wetland on the property south of the project is approximately 10 acres in size. The developer proposes to use this wetland as one of his two means of peak rate runoff control and detention. Special requirement No. 8 of the King County Surface Water Design Manual specifies that the increased volume of runoff from the proposed project may not increase the 100-year floodplain elevation of a wetland more than 0.1 feet. Based on this requirement and the area of the wetland we have estimated, approximately 40,000 cubic feet of storage is available. • Also contained in this report are the calculations for a standard detention system based on City of Renton requirements. These requirements require the developer to match the peak flows of the 2-and 10-year design storm events and increase the required storage volume by 30 percent above the 10-year design storm event. Based on a total build out of the project assuming 90 percent impervious area, the required storage volume would be approximately 60,000 cubic feet. The difference between volume required and volume provided by the wetland is 20,000 cubic feet. This difference must be detained on site. Based on the preliminary water quality calculations, the surface area required for the wet vault is approximately 10,400 square feet. Therefore, 2 feet of storage above the static water surface elevation of the wet vault will provide the necessary on-site storage to make up the 20,000-cubic foot difference. If it is determined that the wetland cannot provide the assumed storage, additional storage will be provided in the on-site wet/detention vault. The outlet control structures from this detention vault would then regulate flows to the wetland and possibly also to the existing 60-inch storm drain in S.W. 19th Avenue. An existing 24-inch pipe currently picks up wetland overflow and conveys it to the 60-inch pipe in S.W. 19th Avenue. Since additional drainage will be reaching the wetland from the site, a storm drainage manhole will be constructed on the existing 24-inch wetland outlet pipe that contains a flow control structure designed in accordance with special requirement No. 8 of KCSWDM. Please refer to the preliminary grading and storm drainage plans for the project for additional information on the storm drainage system. 6045.001 [KL/es] 0134iHy' <swl 1� nrniun H" N,..; >HSI LIMM .dmuT ,purr sr S` an $ " J E . ,t oA < "EHE r J � e` w S 3RD SW SUN j ti s 4TH sY M CT P p0 � S AM K) � S B •eS/S FY BA, •r. $ STN 5T 51N -- A s RR ? 567N Sr < rTH s` 5 s st r J` z eT1 S •n s 7rR CT MIPLow R04MIN Sw vS PAW 1 gi �g s i: vnYf� boy a fig" yROE cn ,�. VILLAGECEKFER 9tx F1C ■ S R VILLAGE PL S IITH Sr �F <E R7 qMA( SZTM St MILIDAY C.Sl �, 7NR CRt�' ,, z 4�. •1f Ln 20 E Y 5 1S7N " q C G \ ST ST t 0 S��� �•P 16� K 16TH ST Q S 16TH sr des gl6n 0. w '� Sim ST I ST p M M 1 G S 1 TH s. TALSOr 4 3 a '•b'� �s`` SW< 0o c3 PUGET • r s< aC � W a� PL e s t SW 23RD ST S 23R0 ST -r-�-- n f♦ i MID i M i "� tx wow •( yy 11` C 62N0< < ST a p i < - Cy ❑ SE 1 iH - Si SE 164TH ST S 27TH ST - 54 $VI -f "j2liFl a 10900 Iu00 u7ro ST s ~s <` s 2M- T: 4 t66r x SE t9S T S n < � �sr - 29TH ST S J s 5T $ SE 16'.S < " Sit I66M l ' ,7j, IF 30 N3 pl R -• < x F 61 6 � E �-K p �1 ISW 3°TM 1srN sr -29 w rtv 331m ST , 32ND 11 SE 169TH l •.., SE 69TH SE 170TH ST 170TN ST °j3 > S '< _ <, < a e iE - € i@G T< SW 711 ST 3A1N ST S SE LRD ST SE 72N0 St.�. ---`=`r-�• &"� IOBDO 7� -- ^�SE 372N0 ST-� -•< 12 aCf�' N < 3 5t 'r9�A•5 d , ,'�� • w p r _sE_ysT_ �1 Si -d •{ '4. :..1 _ 3 ST S 17—ST S Ig ��, LS SE 175 "' 11 • •x Ar SE Cr iST # y` �E sr s 176TI ST SM 41ST ST 5 s `t s -SEE 686 MAP SITE LOCATION MAP 1" = 2400' Reference: The Thomas Guide,King/Pierce/Snohomish Counties, 1996 Edition BeD 00, A ROAD Ty F d R l h No m UrWo — 13--- I —L•, • 1 I � _�� py Golf urse i , l __' I Y A Ur i PAF _ ---------- Sew y o Disp sal •/ - 'ABC } .,s C T M 16 Ag-D 20 BEE Pu tz Longacre4:CIC_ I Pu .•s s •� 515 PY ep SBeC y Ur Wo u• it:,r i (AD ��J, •�• ' r U •" �_ o JTrack " B 29 ' Ur � 1 1 Ng ���t• •�R s rvoir _ _ _ W I me 2 2 .j So Tu z D m 2 W Pu i m Sk Wo M •,� Pu n u .- BM 1 0 = - 29 . 25 1 �203 69 ABC � • �: n PY Sk. / •7. is i, 1 n Wo _ Ur .) T. 1 e KING COUNTY SOIL SURVEY MAP I" = 2000' • STORM DRAINAGE DETENTION CALCULATIONS I • - �u c>s t Gas S ovd-C 6>0 " c o.�c SD 4!%-K DES/ w L-rL.Ati/D (9U" Ganrc 5D lLT ' 9.?S' T-o P Pi PLs t S 2 w� IZ lH/��nT(/M GQO�+Ncef OLT✓ P�Pt3 /(s r llo.S cv Sw l�oY7A �. tR Vf Uf coo An 0 p M a ava N CI N .gSf�M�s So Uri— � d'•�`� O.2S /L l Sri Lives S70R,4 i-g a,-e 3/ //v W LI L ,F ,PIS IL S�7-0 L, !po' R lW J i �i �fr _ 2-0 ' I N 6-z 16.'7s 6 0 to v • i sw 15ne -Z-t,��p • �/s��✓� S/� Lard/97GtiiS •' !�O � S�uc�,✓ moo+-✓ � O,2S'�� H F_tA W W W __= Lp IA VI Vf coo �oa = 3.4 •� �n aaa �a 2os (NO /NtP WOvS \ cv ev r J {Y M CI e.? /9'Ssti clo�� lylp�tZ Vio✓5 -9 ..v : D (14.5� /3 .e S ,4, • '�' S� Fa�o�,✓/N(s P�� �a2 Ca�r�v� r�l�/l e Z 6G7 V6L(/M4T /L-�/D z /d Y2 /'24 to VOL✓M a- 4-3 o e-F) 7 5�3,4 -� As•3 U.crB �, vOCD ter= � 'b 6S S rW460- 0gjW5,TL:f- JA1 ,eyQt;RPQ lgppae4? /0 4caos O-e 4,�w 8 �K�SwDtit� —� ,ti1�Gjc %Nets sty /.J /oo Y2 et-ao'DPuNr� b,to (�-` tO PT • 43 s"w GG i p z Glvsi7� s��'�+4Crr� 2�C1'D -> 2a, aoo cF LUW� W W W W W W 1A VI IA 000 V,�t 1�� •vSLoNs 260 ' 4a ^r / rr r L/vim S�aR 2�61'� z >0,40o s°IZ je • • 3/11/97 1: 45: 46 pm Barghausen Engineers page 1 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS 6045-PRE BASIN SUMMARY BASIN ID: D02YR NAME: POST-DEVELOPED 2YR/24HR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 2 . 00 inches AREA. . : 1. 45 Acres 13 . 05 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 90. 00 98 . 00 TC. . . . . 18 . 10 min 8 . 70 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 50. 00 ns: 0. 1500 p2yr: 2 . 00 s: 0 . 0100 TcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 TcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 impTcReach - Sheet L: 50 . 00 ns: 0. 0110 p2yr: 2 . 00 s: 0 . 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 PEAK RATE: 5. 45 cfs VOL: 2 . 06 Ac-ft TIME: 480 min BASIN ID: D100YR NAME: POST-DEVELOPED 100YR/24HR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 3 . 90 inches AREA. . : 1. 45 Acres 13 . 05 Acres TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 90. 00 98 . 00 TC. . . . : 18 . 10 min 8 . 70 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 50. 00 ns: 0. 1500 p2yr: 2 . 00 s: 0. 0100 TcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0 . 0100 TcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 impTcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0. 0020 PEAK RATE: 11. 22 cfs VOL: 4 . 33 Ac-ft TIME: 480 min BASIN ID: D10YR NAME: POST-DEVELOPED 10YR/24HR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 2 . 90 inches AREA. . : 1. 45 Acres 13 . 05 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 90. 00 98 . 00 TC. . . . . 18 . 10 min 8 . 70 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 50. 00 ns: 0. 1500 p2yr: 2 . 00 s: 0. 0100 TcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 TcReach - Channel L: 850. 00 kc:42 . 00 s: 0. 0020 impTcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 PEAK RATE: 8 . 19 cfs VOL: 3 . 13 Ac-ft TIME: 480 min 3/11/97 1: 45 : 46 pm Barghausen Engineers page 2 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS 6045=PRE_____________________________________________________________ BASIN SUMMARY BASIN ID: EX02YR NAME: PRE-DEVELOPED 2YR/24HR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPElA PERV IMP PRECIPITATION. . . . : 2 . 00 inches AREA. . : 14 . 50 Acres 0. 00 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 0. 00 TC. . . . . 97 . 91 min 0. 00 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 300 . 00 ns: 0. 2400 p2yr: 2 . 00 s: 0. 0050 TcReach - Shallow L: 600. 00 ks: 9 . 00 s: 0. 0025 impTcReach - Sheet L: 50 . 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 PEAK RATE: 1. 03 cfs VOL: 1. 03 Ac-ft TIME: 540 min BASIN ID: EX100YR NAME: PRE-DEVELOPED 100YR/24HR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPElA PERV IMP PRECIPITATION. . . . : 3 . 90 inches AREA. . : 14 . 50 Acres 0. 00 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 0. 00 TC. . . . . 97 . 91 min 0. 00 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 300. 00 ns: 0. 2400 p2yr: 2 . 00 s: 0. 0050 TcReach - Shallow L: 600 . 00 ks: 9 . 00 s: 0. 0025 impTcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 PEAK RATE: 3 . 53 cfs VOL: 2 . 97 Ac-ft TIME: 520 min BASIN ID: EX10YR NAME: PRE-DEVELOPED 10YR/24HR SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 2 . 90 inches AREA. . : 14 . 50 Acres 0. 00 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86. 00 0. 00 TC. . . . . 97 . 91 min 0. 00 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 300. 00 ns: 0. 2400 p2yr: 2 . 00 s: 0. 0050 TcReach - Shallow L: 600. 00 ks: 9 . 00 s: 0 . 0025 impTcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0. 0020 PEAK RATE: 2 . 14 cfs VOL: 1. 91 Ac-ft TIME: 540 min 0 3/11/97 1 : 45 : 46 pm Barghausen Engineers page 3 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS • 6045-PRE BASIN SUMMARY BASIN ID: WETPOND NAME: 1/3 2YR/24HR POST-DEVELOPED SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 0. 67 inches AREA. . : 1. 45 Acres 13 . 05 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 90. 00 98 . 00 TC. . . . . 18 . 10 min 8 . 70 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 50. 00 ns: 0. 1500 p2yr: 2 . 00 s: 0. 0100 TcReach - Sheet L: 50 . 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 TcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 impTcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0. 0020 PEAK RATE: 1 . 41 cfs VOL: 0. 53 Ac-ft TIME: 480 min • • 3/11/97 1: 45: 46 pm Barghausen Engineers page 4 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS • 6045=PRE_____________________________________________________________ HYDROGRAPH SUMMARY PEAK TIME VOLUME HYD RUNOFF OF OF Contrib NUM RATE PEAK HYDRO Area cfs min. cf\AcFt Acres 1 1. 033 800 89812 cf 14 . 50 2 2 . 144 630 136381 cf 14 . 50 3 0. 949 810 89810 cf 14 . 50 4 1. 811 690 136354 cf 14 . 50 5 2 . 576 680 188456 cf 14 . 50 • • 3/11/97 1 : 45 : 50 pm Barghausen Engineers page 5 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS • 6045-PRE STAGE STORAGE TABLE TRAPEZOIDAL BASIN ID No. TRIAL Description: TRIAL DETENTION POND Length: 100. 00 ft. Width: 100 . 00 ft. Side Slope 1: 3 Side Slope 3 : 3 Side Slope 2 : 3 Side Slope 4 : 3 Infiltration Rate: 0. 00 min/inch STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- 10.00 0.0000 0.0000 11.60 17585 0.4037 13.20 38537 0.8847 14.80 63151 1.4497 10.10 1006 0.0231 11.70 18793 0.4314 13.30 39965 0.9175 14.90 64818 1.4880 10.20 2024 0.0465 11.80 20014 0.4595 13.40 41408 0.9506 15.00 66500 1.5266 10.30 3054 0.0701 11.90 21248 0.4878 13.50 42865 0.9840 15.10 68198 1.5656 10.40 4097 0.0940 12.00 22496 0.5164 13.60 44336 1.0178 15.20 69911 1.6049 10.50 5152 0.1183 12.10 23757 0.5454 13.70 45822 1.0519 15.30 71641 1.6446 10.60 6219 0.1428 12.20 25032 0.5747 13.80 47322 1.0864 15.40 73386 1.6847 10.70 7298 0.1675 12.30 26320 0.6042 13.90 48838 1.1212 15.50 75147 1.7251 10.80 8390 0.1926 12.40 27622 0.6341 14.00 50368 1.1563 15.60 76923 1.7659 • 10.90 9495 0.2180 12.50 28938 0.6643 14.10 51913 1.1918 15.70 78716 1.8071 11.00 10612 0.2436 12.60 30267 0.6948 14.20 53473 1.2276 15.80 80525 1.8486 11.10 11742 0.2696 12.70 31610 0.7257 14.30 55048 1.2637 15.90 82351 1.8905 11.20 12885 0.2958 12.80 32967 0.7568 14.40 56638 1.3002 16.00 84192 1.9328 11.30 14040 0.3223 12.90 34339 0.7883 14.50 58244 1.3371 11.40 15209 0.3491 13.00 35724 0.8201 14.60 59864 1.3743 11.50 16391 0.3763 13.10 37123 0.8522 14.70 61500 1.4118 • 3/11/97 1 : 45: 50 pm Barghausen Engineers page 6 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS 6045=PRE_____________________________________________________________ STAGE STORAGE TABLE TRAPEZOIDAL BASIN ID No. TRIAL2 Description: TRIAL DETENTION POND Length: 100. 00 ft. Width: 133 . 50 ft. Side Slope 1: 3 Side Slope 3 : 3 Side Slope 2 : 3 Side Slope 4 : 3 Infiltration Rate: 0. 00 min/inch STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE----> (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- (ft) ---cf--- --Ac-Ft- 10.00 0.0000 0.0000 11.00 14063 0.3228 12.00 29598 0.6795 13.00 46679 1.0716 10.10 1342 0.0308 11.10 15549 0.3569 12.10 31235 0.7171 13.10 48474 1.1128 10.20 2698 0.0619 11.20 17049 0.3914 12.20 32888 0.7550 13.20 50286 1.1544 10.30 4068 0.0934 11.30 18565 0.4262 12.30 34557 0.7933 13.30 52115 1.1964 10.40 5453 0.1252 11.40 20096 0.4613 12.40 36241 0.8320 13.40 53959 1.2387 10.50 6852 0.1573 11.50 21642 0.4968 12.50 37941 0.8710 13.50 55821 1.2815 10.60 8265 0.1897 11.60 23202 0.5327 12.60 39656 0.9104 13.60 57698 1.3246 10.70 9692 0.2225 11.70 24778 0.5688 12.70 41388 0.9501 13.64 58454 1.3419 10.80 11134 0.2556 11.80 26370 0.6054 12.80 43135 0.9903 10.90 12591 0.2891 11.90 27976 0.6422 12.90 44899 1.0307 • 3/11/97 1: 45 : 50 pm Barghausen Engineers page 7 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS 6045=PRE_____________________________________________________________ STAGE DISCHARGE TABLE MULTIPLE ORIFICE ID No. TRIAL Description: TRIAL POND DISCHARGE Outlet Elev: 10. 00 Elev: 8 . 00 ft Orifice Diameter: 4 . 7871 in. Elev: 12 . 90 ft Orifice 2 Diameter: 6 . 3984 in. STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> STAGE <--DISCHARGE---> (ft) ---CfS-- ------- (ft) ---CfS-- ------- (ft) ---CfS-- ------- (ft) ---CfS-- ------- 10.00 0.0000 11.60 0.7866 13.20 1.7210 14.80 2.8939 10.10 0.1967 11.70 0.8108 13.30 1.8324 14.90 2.9478 10.20 0.2781 11.80 0.8343 13.40 1.9323 15.00 3.0005 10.30 0.3406 11.90 0.8572 13.50 2.0240 15.10 3.0523 10.40 0.3933 12.00 0.8795 13.60 2.1095 15.20 3.1030 10.50 0.4397 12.10 0.9012 13.70 2.1899 15.30 3.1528 10.60 0.4817 12.20 0.9224 13.80 2.2663 15.40 3.2018 10.70 0.5203 12.30 0.9431 13.90 2.3391 15.50 3.2499 10.80 0.5562 12.40 0.9634 14.00 2.4090 15.60 3.2972 10.90 0.5900 12.50 0.9833 14.10 2.4762 15.70 3.3438 11.00 0.6219 12.60 1.0028 14.20 2.5412 15.80 3.3896 • 11.10 0.6522 12.70 1.0219 14.30 2.6041 15.90 3.4348 11.20 0.6812 12.80 1.0406 14.40 2.6652 16.00 3.4794 11.30 0.7091 12.90 1.0590 14.50 2.7245 11.40 0.7358 13.00 1.4285 14.60 2.7823 11.50 0.7616 13.10 1.5918 14.70 2.8388 3/11/97 1 : 45: 52 pm Barghausen Engineers page 8 SW 19TH LIND - RENTON PRELIMINARY DETENTION CALCULATIONS • 6045=PRE_____________________________________________________________ LEVEL POOL TABLE SUMMARY MATCH INFLOW -STO- -DIS- <-PEAK-> STORAGE <--------DESCRIPTION---------> (cfs) (cfs) --id- --id- <-STAGE> id VOL (cf) 2YR/24HR PRELIM .............. 1.03 5.45 TRIAL TRIAL 12.76 1 32403.08 cf 10YR/24HR PRELIM ............. 2.14 8.19 TRIAL TRIAL 13.64 2 44972.75 cf 2YR/24HR FINAL ............... 1.03 5.45 TRIAL2 TRIAL 12.33 3 35026.53 cf 10YR/24HR FINAL .............. 2.14 8.19 TRIAL2 TRIAL 13.28 4 51765.48 cf 100YR/24HR FINAL ............. 3.53 11.22 TRIAL2 TRIAL 14.26 5 70413.71 cf • • IN III ' `tip;-'ri'cA•,�1"' l\\ `� � j—;,..� ►,.. No IBM ea", r� "400" I \t�1/ice 1 Opp I �— �'1•�UNPN 5 —���i/�.� .V4.[TJ�T��'Iw� Ow.Ali vrl%v- r. • �� ARM►c':�.,.!l�?t. 7A� �- 32 RO Pip .•cam �� ••-o•••'�1 �'• 1 0-21 LAI 01 1. ,W. .'ro W g M, : nMt �/; tc�;. •Pr. !2 —�iu�`�:..� .. L�"����fir,.W, low ow jI�/ -%��j)� ,•cam r, t ►.R w � � c.»L•. I �.1 � � i 1 rn\ � ,'�`.; �,��1'� Cam[: \��'� ► IN '_rA Ls Ammo flSri/���!�MR I / 1 ►_:-A ► •1 ��' _.''� �/��� •�`"� . �R •.ur all r� NOR; �� :, � why � ...�� `•�•Z�c;��IMI �•����" d.,� ^a • • _ \ir k .-av ,l�v r of*1%,� MAIM Wl MM IRWIN 11 i� r �� t• � v ,�"•• MA VIM I. `� t�Yt,�� :1 / ' ���. C`► `l�, `i[��� � �?f! �v :Arles � 1 � / ,/� ,/ice• .T'�' � �� (� .�+. V♦._ ri[ '.I 11 '' �l�• I ��.��c.. -mac- �-.�iir► � ��. s ORS , �.• ,� ��'cf��►/.i)/i'���,! a l�il 1 1 11 1 •��j'S'1 f��� � � / � 1 1 .1 WATER QUALITY CALCULATIONS i I<CGusDM 2/4G pooz5- 5$e-S7ar V.16-rPCOL 70 C-INOFT VOLvvi� 9-qf A./AOtw eVeA1-- sew F�6 twze 6,4• l.1a ) fC = o. 47 /,W• maMAul W MAW LL,sxx /� /4•S ,4c , N t/f t/f coo v1 O O C4 fZ fiNC F'$ a a a —> w G NI CC4 N C C.Q G a 1-4 z 83. V =(vb/Vr) 5 � 43slb/yl • / 43�60 3 �o•47) 14 (D. 835-� ( /z ) 6/,970 CF v1'd y !o!, a �N F fZ 7,- Uz,� 2,oUf x 46 e g9 rr (n.CL"f 2` Give SFa2sq�g ) foe 0 Ff SECTION 6.4 PONDING WQ FACILITY DESIGNS to the water quality facili, . Other water quality facilities may be more cost-effective for serving drainage areas less than 2 acres, particularly if a detention pond is not required for the site. A wetpond may remove some dissolved pollutants such as phosphorus. However, biological activity and adsorption to plant surfaces, believed to be the primary removal mechanisms of dissolved pollutants, may not be significant during the winter months in King County. 6.4.1.1 METHODS OF ANALYSIS Included in this section are the methods of analysis for the following two wetpond applications: • Basic wetpond (see below) • Large wetpond (see page 6-59) ❑ BASIC WETPOND The primary design factor that determines particulate removal efficiency of the wetpond is the volume of the wetpool in relation to the volume of the stormwater runoff, known as the Vb/Vr ratio." The larger the Vb/Vr ratio, the greater the potential for pollutant removal. A secondary factor is the pond's hydraulic efficiency,that is, the rate of exchange between the water in the pond and the incoming water from each storm. Hydraulic efficiency is improved by avoiding dead zones (like corners) where little exchange occurs, by using large length-to-width ratios, and by maximizing the flow path between inlet and outlet. Wetponds designed using the method of analysis outlined below and the required design criteria in Section 6.4:1.2 are expected to meet the goal of the basic WQ menu (80%TSS removal).The actual performance of a wetpond may vary, however, due to a number of factors including design features, maintenance frequency, storm characteristics, pond algae dynamics and waterfowl use. The required minimum wetpool volume is based on the volume of runoff from the tributary drainage area for the mean annual storm, a statistically derived rainfall event. Procedures for determining the • wetpool dimensions and volume are outlined below. Step 1. Identify minimum required ratio of wetpool volume to runoff volume (Vb/Vr). The basic wetpond requires a minimum Vt/Vr ratio of 3. Step 2. Determine mean rainfall event (R). The mean rainfall event coefficient (R) is obtained by locating the project site on Figure 6.4.1.A (p. 6-58) and interpolating between isopluvials. Step 3. Determine wetpond tributary area (Ad). The wetpond tributary area (Ad) is composed of pollution-generating impervious areas and other areas that drain to the wetpond under post- development conditions. Step 4. Calculate runoff coefficient (C). The runoff coefficient represents the amount of rainfall that runs off a particular set of land covers. To determine the runoff coefficient (C), each portion of the wetpond tributary area is assigned to one of four cover types, each having a different runoff coefficient: impervious surface, till grass, till forest, or outwash. 1. Impervious surface is a compacted surface,whether paved, graveled, soil, or other hard surface, as well as a pre-existing soil, gravel, or other similar compacted surface. (Open water and wetland areas draining to the water quality facility are classified as impervious surfaces.) 2. Till grass is post-development grass or landscaped area and onsite forested land on till soil not protected by covenant or native growth protection tracts. Till is soil that does not drain readily and, as a result, generates large amounts of runoff. Till soil types include Buckley and bedrock soils, and alluvial and outwash soils that have a seasonally high water table or are underlain at a shallow depth (<5 feet) by glacial till. U.S. Soil Conservation Service (SCS) hydrologic soil groups that are classified as till soils include a few B, most C, and all D soils. See Chapter 3 for classification,of specific SCS soil types. U.S.Environmental Protection Agency,Results of the Nationwide Urban Runoff Program, 1986. October 1995 Draft Surface Water Design Manual 6-56 6.4.1 WETPOND--METHODS OFANALI SIS 3. Till forest is all permanent onsite forest/shrub cover located on till soils that retains the natural understo.ry vegetation and forest duff, irrespective of age if densities are sufficient to ensure at least 80 percent canopy cover within 5 years. To be counted in this category, forest must be protected by covenant or a non-developable tract. 4. outwash is soil that infiltrates well and as a result produces small amounts of runoff. SCS hydrologic soil groups classified as outwash soils include all A, most B, and some C soils. See Chapter 3 for classification of specific SCS soil types. Each portion of the wetpond tributary area is assigned to the appropriate cover category based on existing U.S. Department of Agriculture soil survey data or site specific data where available. Next, coefficients specific to the four cover types are weighted by the drainage areas to produce the runoff coefficient (C): C_ 0.9A; +0.25At9 +0.10Att +0.01Ao (1) Ad where, C = runoff coefficient (unitless) A; = area of impervious surface (acres) Atc = area of till soil covered with grass (acres) Atf = area of till soil covered with forest (acres) Aa = area of outwash soil covered with grass or forest (acres) Ad = wetpond tributary area = A;+At9+Atf+Ao (acres). • Draft Surface Water Design Manual October 1995 6-57 6.4.1 WFITOND--METHODS OFANALYSIS Step 5. Calculate wetpool design volume (Vb). Use the results of the previous steps to calculate the wetpool design volume according to the following equation: (V., C43,5601 (2) Vb =I Vr I RAdC 12 JJ l J where, Vb = wetpool volume (cu ft) V,,/Vr = wetpool volume to runoff volume (unitless) R = mean rainfall coefficient (inches) 43,560 =12 = conversion factor for square feet/acres. Step 6. Determine wetpool dimensions. Determine the wetpool dimensions based on the design criteria outlined below. A simple way to check the volume of each wetpool cell is to use the following equation: h(Aj +A2) Vb 2 (3) = where, V = wetpool volume (cu ft) h = wetpool depth (ft) A, = water quality design surface area of wetpool (sq ft) A2 = bottom area of wetpool (sq ft). ❑ LARGE WETPOND Wetponds designed using a Vb/V,ratio of 4.5 and the method of analysis and required design criteria in this section are expected to meet the goal of the sensitive lake WQ menu (50% total phosphorus removal). The actual performance of a wetpond may vary, however, due to a number of factors including design features, maintenance frequency, storm characteristics, algae dynamics and waterfowl use. The methods of analysis presented above for the basic wetpond apply to the large wetpond, except that step 1 is modified as follows: Step 1. The large wetpond alternative requires a minimum Vb/Vr ratio of 4.5. Draft Surface Water Design Manual October 1995 6-59 SECTION 6.4 PONDING WQ FACILI"IY DESIGNS FIGURE 6.4.1.A PRECIPITATION FOR MEAN ANNUAL STORM (INCHES)" o= / t r •��,\ inn — _ r p- ! �-^ca` z— t w ( b t � � J r f I 0.54 0.47 �l 0.47 .�,CL-I—� 0.52 .e., 0.56 0.65 Note: Areas east of the easternmost isopluvial should use 0.65 inches unless rainfall data is available for the location of interest. 12 The mean annual storm is a conceptual storm found by dividing the annual precipitation by the total number of storm events per 0 year October 1995 Draft Surface Water Design Manual 6-58 I • � S,q � /'J ��,�. iM��n viov s So.2F�� �2c�1 85� No ,B eoSwllct;� 1/1 IA M W W W 0"to 000 N O O ,4ss .tie 90 i ✓�o✓s > p. 4 �l4 . ) l3.aS Az A A CI n r N � see ����2)�a.o>� ��.as' •�� �44,5� ���� � �/37d se �- 1/d L Ste" �� GALL — vs �3 Z72 Im An- ve✓e—op0-9 S'zao 23, &Z Gr • 4 use 204+x *0 62 lgo x lov' 570 G/s r�vQ G+-S i4/Z eke u5 dD z 0,32 8 cR • 3/11/97 10 : 39 : 41 am Barghausen Engineers page 1 SW 19TH LIND - RENTON PRELIMINARY WETPOND CALCULATIONS 6045=PRE10 _____________________________________________________________ BASIN SUMMARY BASIN ID: WETPOND NAME: 1/3 2YR/24HR POST-DEVELOPED SBUH METHODOLOGY TOTAL AREA. . . . . . . : 14 . 50 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 0. 67 inches AREA. . : 1. 45 Acres 13 . 05 Acres TIME INTERVAL. . . . : 10. 00 min CN. . . . : 90 . 00 98. 00 TC. . . . . 18 . 10 min 8 . 70 min ABSTRACTION COEFF: 0. 20 TcReach - Sheet L: 50. 00 ns: 0. 1500 p2yr: 2 . 00 s: 0. 0100 TcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 TcReach - Channel L: 850. 00 kc: 42 . 00 s: 0. 0020 impTcReach - Sheet L: 50. 00 ns: 0. 0110 p2yr: 2 . 00 s: 0. 0100 impTcReach - Channel L: 850. 00 kc: 42 . 00 s: 0 . 0020 PEAK RATE: 1. 41 cfs VOL: 0. 53 Ac-ft TIME: 480 min • 0 0r> O X.Z.,z.OF, 627. -0007070¢GZ -....... . .. .. . . . _ . . . ._ . . . . . . ... ... . . . . . . 77iG/co93o (L/ND 4VE.,l . . . . ... . . . . 329,54 i32J, 3B ` B//O SOS'Oo BZo Z/Co 03SZ-/(7' ' o�\ N _ . . . . . . . . . . �� 85D,7/G�OZ-5• cc 00 ZD -/GE 1 p # l A�vrzox C of Ieo Y6ftc e Fl-Xo t-Ime ;C t4LD), tLn th ��. > A6 L Ln L4Lri : m M ltkJ 0s 0 I .59 Aj 574 aJ ; o : . . . . . . . . . . . . . . . . . . . : . . . �` I �PAOl 2 AVE) u AJO1-23_ po �0 0 — (� :` (,'• ;t. a:: Z ,z. 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GUIDE TO MAPPING UNITS--Continued Woodland Described Capability unit group Map on symbol Mapping unit page Symbol Page Symbol Re Renton silt loam-------------------------------------------- 26 IIIw-1 75 awl Rh Riveiwash--------------------------------------------------- 27 VIIIw-1 78 --- Sa Salal silt loam--------------------------------------------- 27 IIw-1 74 2ol Sh Sammamish silt loam----------------------------------------- 27 IIw-2 75 awl Sk Seattle muck------------------------------------------------ 28 IIw-3 75 --- Sm Shalcar muck-------------------------------------------- ---- 29 IIw-3 75 --- Sn Si silt loam------------------------------------------------ 29 IIw-1 74 2ol So Snohomish silt loam------------- --------------------------- 30 IIw-2 75 3w2 Sr Snohomish silt loam, thick surface variant------------------ 31 IIw-2 75 3w2 Su Sultan silt loam-------------------------------------------- 31 IIw-1 74 3wl Tu Tukwila muck------------------------------------------------ 32 IIw-3 75 --- UrUrban land--------------------------------------------------- 33 -------- -- --- Wo Woodinville silt loam--------------------------------------- 33 IIw-2 7S 3w2 1/ The composition of these units is more variable than that of the others in the Area, but it has been controlled well enough to interpret for the expected use of the soils. • GUIDE TO MAPPING UNITS For a full description of a mapping unit, read both the description of the mapping unit and that of the soil series to which the mapping unit belongs. See table 6, page 70, for descriptions of woodland groups. Other information is given in tables as follows: Acreage and extent, table 1, page 9. Town and country planning, table 4, page 57. Engineering uses of the soils, tables 2 and 3, Recreational uses, table S, page 64. pages 36 through 55. Estimated yields, table 7, page 79. Woodland Described Capability unit group Map on symbol Mapping unit page Symbol Page Symbol AgB Alderwood gravelly sandy loam, 0 to 6 percent slopes---------- 10 IVe-2 76 3d2 AgC Alderwood gravelly sandy loam, 6 to 15 percent slopes--------- 8 IVe-2 76 3dl AgD Alderwood gravelly sandy loam, 15 to 30 percent slopes-------- 10 VIe-2 78 3dl AkF Alderwood and Kitsap soils, very steep------------------------ 10 VIIe-1 78 2dl AmB Arents, Alderwood material, 0 to 6 percent slopes 1/---------- 10 IVe-2 76 3d2 AmC Arents, Alderwood material, 6 to 15 percent slopes 1/--------- 10 IVe-2 76 3d2 An Arents, Everett material 1/----------------------------------- 11 IVs-1 77 3f3 BeC Beausite gravelly sandy loam, 6 to 15 percent slopes---------- 11 IVe-2 76 3d2 BeD Beausite gravelly sandy loam, 15 to 30 percent slopes--------- 12 VIe-2 78 3dl BeF Beausite gravelly sandy loam, 40 to 75 percent slopes--------- 12 VIIe-1 78 3dl Bh Bellingham silt loam------------------------------------------ 12 IIIw-2 76 3w2 Br Briscot silt loam--------------------------------------------- 13 IIw-2 7.5 awl Bu Buckley silt loam--------------------------------------------- 13 IIIw-2 76 4wl Cb Coastal beaches----------------------------------------------- 14 VIIIw-1 78 --- Ea . Earlmont silt loam-------------------------------------------- 14 IIw-2 75 3w2 Ed Edgewick fine sandy loam-------------------------------------- 15 IIIw-1 75 2ol EvB Everett gravelly sandy loam, 0 to 5 percent slopes------------ 15 IVs-1 77 3f3 EvC Everett gravelly sandy loam, 5 to 15 percent slopes----------- 16 VIs-1 78 3f3 EvD Everett gravelly sandy loam, 15 to 30 percent slopes---------- 16 VIe-1 77 3f2 EwC `Everett-Alderwood gravelly sandy loamy, 6 to 15 percent Islopes------------------------------------------------------ 16 VIs-1 78 3f3 InA Indianola loamy fine sand, 0 to 4 percent slopes-------------- 17 IVs-2 77 4s3 InC Indianola loamy fine sand, 4 to 15 percent slopes------------- 16 IVs-2 77 4s3 InD Indianola loamy fine sand, 15 to 30 percent slopes------------ 17 VIe-1 76 4s2 KpB Kitsap silt loam, 2 to 8 percent slopes----------------------- 17 IIIe-1 75 2d2 KpC Kitsap silt loam, 8 to 15 percent slopes---------------------- 18 IVe-1 76 7d2 KpD Kitsap silt loam, 15 to 30 percent slopes--------------------- 18 VIe-2 78 2dl i KsC Klaus gravelly loamy sand, 6 to 15 percent slopes------------- 18 VIs-1 78 3fl Ma Mixed alluvial land------------------------------------------- 18 VIw-2 78 2ol 1 NeC Neilton very gravelly loamy sand, 2 to 15 percent slopes------ 19 VIs-1 78 3f3 t ------- --------- --------- -:f Ng Newberg silt loam---------- ----- --- -- 19 IIw-1 74 201 Nk Nooksack silt loam-------------------------------------------- 20 IIw-1 74 2o1 No Norma sandy loam---------------------------------------------- 20 IIIw-3 76 3w2 ------------------ -------- --- ' Or Orcas peat------- ---- --------------- 21 VIIIw-1 78 Os Oridia silt loam---------------------------------------------- 21 IIw-2 75 3w1 OvC Ovall gravelly loam, 0 to 15 percent slopes------------------- 22 IVe-2 76 3dl y OvD Ovall gravelly loam, 15 to 25 percent slopes------------------ 23 VIe-2 78 3dl OvF Ovall gravelly loam, 40 to 75 percent slopes------------------ 23 VIIe-1 78 3dl '! Pc Pilchuck loamy fine sand-------------------------------------- 23 VIw-1 78 2sl Pk Pilchuck fine sandy loam-------------------------------------- 23 IVw-1 76 2sl Pu Puget silty clay loam----------------------------------------- 24 IIIw-2 76 3w2 }. Py Puyallup fine sandy loam------ --- 24 IIw-1 74 2ol ---------- ------------------ RaC Ragnar fine sandy loam, 6 to 15 percent slopes---------------- 25 IVe-3 77 4sl RaD Ragnar fine sandy loam, 15 to 25 percent slopes--------------- 26 VIe-2 78 4sl RdC Ragnar-Indianola association, sloping: 1/---------------------- 26 -------- -- Ragnar soil--------------------------------------------- -- IVe-3 77 4sl Indianola soil------------------------------------------- -- IVs-2 77 4s3 r., RdE Ragnar-Indianola association, moderately steep: 1/------------ 26 -------- -- --- Ragnar soil---------------------------------------------- -- VIe-2 78 4sl Indianola soil------------------------------------------- -- VIe-1 77 4s2 U.S. GOVERNMENT PRINTING OFFICE:1973 0-468-26E ..�I : ; I ; : �= AJ59-3.5-33E 1 I ,`a _ 222.9G NB9-.�s• E, 2ao. LOT: 2 . . . . . . . : . . . . . . . . : . . . . . . . . . . . 256.14 �- � ''• : q . . . . " LOT 4 t , ' m \ 121 , I . . . . . . . . . . _ . . . . . . . . . . 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