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HomeMy WebLinkAboutStorm Drainage Analysis Report - PLN General - 3/22/2004 PLANNING Michael F. Wnek, P.E., PS Consulting Civil Engineer 1665 NW Sherwood Drive, Bremerton, WA 98311, 360-692-3802 STORM DRAINAGE ANALYSIS REPORT FOR Richard Eager Located in the NE 1/4 of SEC 23, T 281 R 1 E X.M. Mason County Assessor's Account No. 12328-23-90010 Richard Eager 8128 187th St SW Edmonds WA. 98026-5843 (360) 649-4005 March 22, 2004 Michael F. Wnek, P.E. Consulting Civil Engineer Cl) 16550NW Sherwood Drive f Bremerton, Washington 98311 ' If (360)-692-3802 RECEIVED p ° 66°GISTt °�' Job#304 MAY 2 8 2004 O��SS/ONAL March 10, 2004 426 W. CEDAR ST. EXPIRES 07/1 aros TABLE OF CONTENTS PROJECTOVtRVIEW.................................... ......... ... ...... .. ...... ... ...... EXISTING SITE CONDITIONS...................... ................. DEVELOPED SITE CONDISTIONS................. .................—. —............. DOWNSTREANANALYSIS................................I...................I........... EROSIONCONTROL... .............................................................. 2 WATER QUALITY DESIGN............. ........... ...... ....... .................. 2 APPENDICES Appendix A—Various Maps Appendix B— Soils information, Cn Values, Isopluvials Appendix C—Basin Runoff Calculations Appendix D—Water Quality PROJECT OVERVIEW The site is 3.7 acres total and is located in the Northeast quarter of the Northeast quarter of Section 23 Township 28 range 1 E in Mason County, Washington. The storm drainage analysis and design will be reviewed by Mason County and based in requirements as found in the Dept. of Ecology, Storm Water Management Design Manual for the Puget Sound Region. The Santa Barbara Urban Hydrograph method will be used to compare the peak runoff rates for the existing site conditions and the proposed changes to the site, modeling the 100 year, 24 hour storm events. The StormShed 2G software program by Engenious Systems, Inc. has been used for hydrograph calculations and Level Pool Routing. Infiltration is proposed as the method of meeting the requirements for runoff quantity contriol. There will be no off site improvements required. Storm water runoff from the site does not discharge directly into a stream, so a Hydraulic Project Approval application is not required. EXISTING SITE CONDITIONS The site is currently undeveloped with trees and brush. The site slopes from the east to west with an average slope of 20 percent. Access to the site will be from Roy Boad Road. The area for the proposed building and access road has already been cleared and partially graded. Soil Conservation Service maps for the area show that the soil is typically found to be "Event gravelly loamy sand" belonging to the Hydrologic Group "A". A copy of the SCS maps for the site is attached with this report. Existing peak storm runoff rate calculations are not warranted, since there will be no post development discharge, due to the infiltration system. DEVELOPED SITE CONDITIONS Development of the 3.7 acres will consist of 0.33 acres of impervious surface (roof- top, asphalt parking,and driveways). The pervious area will be in the form of native vegetation. The soil where the infiltration pit will be placed is coarse sand and gravel. The infiltration rate from Table III-3.1 (attached in Appendix C) is 20in/hr. A safety factor of 2 is applied to the rate, therefore 10 inches per hour is used in the system calculations. The 100-year, 24-hour event is the basis for sizing the infiltration trench. DOWNSTREAN ANALYSIS OF CONVEYANCE SYSTEM The upstream potion of the site encompasses 3.42 acres and will be diverted around the infiltration facility with a cut-off ditch. The project impervious-area drainage will flow through a Biofiltration Swale to a infiltration pit, which will deliver the water to the ground. The overflow will go to an existing storm system on the East side of Roy Boad Rd. The storm system flows under Roy Boad Road in a 24" culvert to the west side, which connects to an existing stream that carries the flows east to Lynch Cove. The storm system along Roy Boad Road has been recently constructed by Mason County project CRP#1702. EROSION CONTROL A silt and erosion control plan for this site is included with the final construction plans. WATER QUALITY All of the runoff water from the paved surface and buildings will be treated in a biofiltration swale prior to discharge from the site. The length of the Bioswale has been shortened to 1/3 by tripling of the width. The locations of the biofiltration swale is shown in the report. Swale design and storm water quality facilities can be found.in Appendix D of this report. APPENDIX A VARIOUS MAPS AND SOIL INFO Vicinity Map Al USGS Map A2 Soils Map A3 Soil Description A4 Soil Group. A5 COURT EY cgFFK I. ! ly Lu a� uj MAKEVA PO HOLT RD I NEWKIRK RD`HIUSI --- ---------- ------ ---------------------- ASR ---------- --------------4-- -- ---y-` ---- -----'- ----- ------- -- -- -- - - - -- i ' � W E ,LN i �Js i 2 7 N i �� � S LL p 90 ' UiU SCOOTER LN I clf �Ei Q - TIMBERLINE DR McKNIG.. .,, --_-- -- - --1-- 's`--- 0 ---- - -- ---=----------------- -------------- --------- --- -- -------------------- - i RD Z = 'snnoruu DAVIS FARM RD L FS 2-1 Q ! MF PARK cc SAND HILL FERN RIDGE POINT BLVD W FpVQ` ELEM.SCHOOL -WAY g O O I{ w ¢ -ANS()N ¢ LAKE COKELET LN ! J DER �HEP a� �P KIMBERLY Da - -_ --- - ------ ---- -�i - --- -------y e - _i - -----Qt� ------------Ma"r--- - - - --- -----'--- - --- ---- - --------------- F k �q 3 °� GALLEY c�LV ALDERWOOD �1pF(0t1/. MASON COUNTY Q PL , LN1il. COURTHOUSE ANNEX i ! cc I "' 'F 3� BELFAIR I C, qtF v BELFAIR NYARD C �+~ TS o � V~ ,,,,.,�' ST i 1 J T ✓ ANCHO R WAY N SEl7z ' P` i N• -� s�C ' .. i !.. o ------ ----------------------- - s $ BEARDS COVE pr y BEACH PARK i ! w � t BER aft BYERLY cpw i U "'3. yq`¢ �'9 BEARDS DR AIR CASTLE LN i I COVE CIF . BELFAIR i o t ■ ELEM.SCHOOL ,. �_ -----------------------------------------'('--------------------i--------'-' - - -------------------------------------------- ------- ---F•----- 0 LORRAIN CT - R Cp MATHEW CT I P N 3 h NATHERINE CT SQUIRE LN n Zv 1 / `Ij it /:,�%: , �-' � / � � � •. -. • %t: ,••" •- ( / ,', ;•�tii;� /�i; T--',�; 1 \`(fir-=r�� /r // � .•.` �• i : ' '• / --/ ` ; �.,v � �J ti: / � ass •� � \"�, �' �f'' �� � ��'' // �� • s a. � / ��`: Jam• Ilia '• I! , , 'J r NO ki ——`�"^--'-�� � _1'�� �''*-ice\ � --' �■ I_ � j,! — ter.%-., -....' (i��. : �:� •�� .�;� ■ � • ; // h _ i ----<�-J• (� 'lr x it }ate -,_�. '\•y• t.,� r�;'��'ly 5� r 2';��t�� lt'� ,� /fey\� �• '�e .m ��, � �!� (/Y _ m , 1 - _. 0 17 711 T. 41 Zs tr ate. _ -_-- V � x''~'^' �`` •�,�' -t,; , VY \ ��T '��• \ '�.:` a� v �•I•��Kl�` •,;'W. vet.. �� ZIA tt All y � t, �.� il� �'` �� '•� .:tip '- � ✓ 1� -�/1A,� �{ :,\ \�. ��O t 1,�,� �^ In• �,��•,.+-�. - �••1 �,--� "�"��`�.. ._._,z�,,--t„'-•---.. t — \ � �...-,--,1`n,---\ l` „v �,, is 'tea 1 � �• • " � . . `'ram'... � ���` ` x^` � `~`. ("�%^``"�� �y-� ..(; � _..-/r;� ♦•II ., 1 ✓ `.�, , L; TI �o. � Cn�.S� 1 � mil` •. tr�'{� �' Y r. PIERCE C.UUNTY I MTSAF COUNT 24 SOIL SURVEY SERIES 1951, NO. 9 The Eld soil occurs only in the extreme southern end material that is extremely loose and porous. However, of the county. It differs from the Ma own soils in in places, this material will stand in banks. The color having a redder surface soil and subsoil, some faintly of this material is largely determined by the gravel. developed shot, and stronger red and yellow staining of coarse sand, and cobbles, which are olive gray, pale the subsoil. olive, yellowish brown, light brownish gray, gray, and Eld silt loam, 0 to 3 percent slopes (Ec).—This soil is dark gray. Many of the cobbles, as well as much of the at the head of Oyster Bay. The surface soil is reddish- gravel, are faintly to moderately stained by iron. brown, granular and friable silt loam, 6 to 10 inches The amount of gravel ranges from about 20 percent tc thick, that contains a few very soft shot. This layer is 50 percent in the subsoil to as much as 80 percent in the underlain by a reddish-brown, firm clay loam that has substratum. The soil is medium to strongly acid and a subangular blocky structure, is highly stained by iron, becomes less acid with depth. and contains considerable amounts of shot. At depths USe and Suitability.—This soil is too droughty for ranging from 20 to 32 inches, the clay loam rests on most tilled crops—it dries out before crops mature. a layer of fairly compact, stratified sand and gravel that Only a very small acreage is cultivated, and this is is prominently stained by iron. Rounded glacial gravel, ordinarily farmed along with better adjacent soils. Most mixed with subangular basaltic gravel, is scattered on of this soil is in brush and trees, for which it is suited the surface and through the soil. best. It is one of the better soils for growing Douglas- The soil is medium acid throughout. Surface drainage firs that are cut for Christmas trees. This is an impor- is moderately well established though small swales may taint use of the soil; large acreages are used for Christ- stay wet for a long time. Suisurface drainage is fairly mas trees. slow because of a slowly receding, fairly high water This soil is in capability subclass VIs and in site table. class 4 for Douglas-fir. Use and Suitability.—Most of the soil is used for Everett gravelly sandy loam, 0 to 5 percent slopes pasture or grain. Management is similar to that of (Eg).—This soil occupies the smoother outwash terraces in Ma own silt loam, 0 to 3 percent slopes, but yields are association with other Everett soils. It differs from slightly lower. Everett gravelly sandy loam, 5 to 15 percent slopes, in This soil is in capability subclass IIIs; it is good for that its surface layer is generally 2 to 3 inches thicker; fir, redcedar, hemlock, and deciduous trees. the profile is less variable; and the substratum, or under- lying material, is usually more stratified. EVERETT SERIES Use and Suitability.—The use of this soil is similar to The Everett series consists of somewhat excessively that of Everett gravelly sandy loam, 5 to 15 percent drained, pale-brown gravelly soils. They occur as inex- slopes. The soil is in trees and brush, except for a few tensive gravel ridges on the glacial moraines, or, more small cleared areas. The growing of Douglas-fir for m comonly, as fairly continuous outwash channels be- Christmas trees is gaining in importance. This soil is in tween ridges of Alderwood soils. They have developed site class 4 for Douglas-fir and in capability subclass VIs. it an outwash material. The loam, 15 to 30 percent slopes upon assorted glacialt l d Everett gravelly sandy p p rainfall is 45 to 60 inches a year. The vegetation is (Ek).—This soil is on the steeper slopes of glacial moraines, mainly drought-resistant madrone, manzanita, and kin- sides of gullies, and terrace fronts. It is closely asso- nikinnick. ciated with other Everett soils and the Alderwood Everett soils are droughty because the loose gravel and gravelly sandy loams. sand subsoil and substratum offer little resistance to This soil is more variable than Everett gravelly sand y �' y y downward movement of water. The capacity of the sur- loam, 5 to 15 percent slopes. The depth to substratum face soil to hold available moisture is low. ranges from 12 to 36 inches, and the amount of gravel Everett soils are in the eastern half of the county, in in the surface soil and subsoil varies greatly from place association with the Alderwood soils. They also occur to pplace. Where the soil is in close association with the in intricate patterns with the Kitsap and Indianola soils. Alderwood soils, the substratum, in places, is compact Compared to the Grove soils, the Everett soils have a and weakly cemented. paler surface soil and subsoil and, in development, were Included are a few areas having slopes slightly greater dominated more by acid igneous parent rock. than 30 percent. Everett gravelly sandy loam, 5 to 15 percent slopes Use and Suitability.—This soil is suitable only for (Eh).—This is the most extensive Everett soil. In undis- forestry because it is strongly sloping, droughty, and low turbed forests 1 to 2 inches of verydark grayish-brown in fertility. It is in capability subclass VIs and in site material a mixture of needles leaves twigs, cones moss class 5 for Douglas-fir. and roots, covers the surface. The surface soil is loose, Everett gravelly loamy sand, 0 to 5 percent slopes single-grained, pale-brown, gravelly sandy loam, 6 to 8 (Ed).—This soil occupies the smoother terraces or outwash inches thick. The upper 2 or 3 inches normally contains plain in close association with other Everett soils. It aggregates that are slightly hard and redder than the differs from Everett gravelly sandy loam, 5 to 15 percent others in the layer. To depths ranging from 18 to 24 slopes, in having a finer surface soil and a slightly inches, g �'a the subsoil is loose sin le- rced, light yellow- coarser subsoil. g ish-brown gravelly sandy loam or gravelly loamy sand. Use and Suitability.—Use and management are similar The amount of shot decreases with depth; in the lower to those for Everett gravelly sandy loam, 5 to 15 percent part only a few shot occur. slopes. This soil is poorer for forest than Everett The subsoil grades to a substratum of poorly assorted,, gravelly sandy loam 0 to 5 percent slopes. It is in predominantly yellowish-brown sand, gravel, and cobbly capability subclass VI2s and in site class 5 for Douglas-fir. � �4 .rr^ T OF AGRICULTURE ON SERVICE MASON COUNTY, WASHINGTON SOIL LEGEND SYMBOL NAME SYMBOL NAME Aa Alderwood gravelly loam, 5-15 percent slopes He Harstine gravelly sandy loam, 5-15 percent slopes Ab Alderwood gravelly sandy loam, 5.15 percent slopes Hb Harstine gravelly sandy loam, 15.30 percent slopes Ac Alderwood gravelly sandy loam, 15-30 percent slopes He Hoodsport gravelly sandy loam,0.5 percent slopes Ad Alderwood gravelly sandy loam, 30-45 percent slopes Hd Hoodsport gravelly sandy loam, 5-15 percent slopes Ae Astoria silt foam, 5.15 percent slopes He Hoodsport gravelly sandy loam, 15-30 percent slopes At Astoria silt loam, 15.30 percent slopes Hoodsport gravelly sandy loam, 30-45 percent slopes Hg Hoodsport stony sandy loam, 5-15 percent slopes Be Belfast sandy loam, 0.3 percent slopes Hh Hoodsport stony sandy loam, 15-30 percent slopes Bb Belfast silt loam, 0-3 percent slopes Hk Hoquism gravelly lilt loam, 5.15 percent slopes Bc Belle silt loam, 0-5 percent slopes Hm Hoquism gravelly silt loam, 15-30 percent slopes Bd Bellingham silt loam, 0-3 percent slopes Hn Hoquism loam, 15.30 percent slopes Be Bellingham silty clay loam, 0-3 percent slopes Ho Hoquism silt loam,0-5 percent slopes Ca Cerstairs gravely loam, 0-5 percent slopes His Hoquism sitt loam, 5.15 percent slopes Cloquallum silt loam, 0.5 percent slopes Hr Hoquism silt loam, 15-30 percent slopes Cloquallum silt loom, 5-15 percent slopes Hs Hoquism and Astoria slit loam$, 5-15 percent slopes Cloquallum silt loam, 15-30 percent slopes Ht Hoquism and Astoria silt looms, 15-30 percent slopes Cloquallum silt loam, moderately shallow over Is Indianola loamy sand, 0-5 percent slopes cemented..till, 5.15 percent slopes Ib Indianola loamy sand, 5-15 percent slopes Cf Cloquallum silty clay loom, 5-15 percent slopes Ic Indianola loamy sand, 15-30 percent slopes Cg Coastal beach, 0-2 percent slopes Id Indianola sandy loam, 0-5 percent slopes Do Deckerville gravelly loam, 0-2 percent slopes le Indianola sandy loom, 5-15 percent slopes Deckerville gravelly silty clay loam, 0-2 percent slopes Deckerville silt loom, 0-2 percent scones Js Juno gravelly sandy loom, 0.3 percent slopes Dd Deckerville silty clay loam, 0-2 percent slopes Jb Juno loom, 0-3 percent slopes ^' Delphi gravelly loam, 5-15 percent slopes Jc Juno loamy send, 0-3 percent slopes Delphi gravelly loam, 15-30 percent slopes Jd Juno sandy loam, 0.3 percent slopes Dg Dungeness fine sandy loam, 0.2 percent slopes Ks Kitsap silt loam, 0.5 percent slopes Dungeness fine sandy loam, shallow, 0-2 percent slopes Kb Kitsap silt loam, 5.15 percent slopes Dungeness silt loom, 0.2 percent slopes Kc Kitsap silt loam, 15.30 percent slopes Kd Kitsap silty clay loom, 0-5 percent slopes Ea Edmonds fine sandy loam,percent percent slopes Ke Kitsap silty clay loam, 5-15 percent slopes Eb Edmonds silt loam, rc percent slopes Kf Koch gravelly loam,0.3 percent slopes Ec Eld etc loam, 0-3 percent slopes Kg Koch gravely sandy loam, 0.3 percent slopes Ed Everett gravelly loamy sand, 0-5 percent slopes Kh Koch silt loam, 0-3 percent slopes Ee Everett gravelly loamy sand, 5-15 percent slopes Ef Everett gravelly loamy sand, 15-30 percent slopes LE Le Bar silt loam, 0-5 percent slopes ES Everett gravelly sandy loam, 0-5 percent slopes Lb Lystsir loamy send, 0.5 percent slopes Eh Everett gravelly sandy loam, 5.15 percent slopes Le Lystalr loamy send,5-15 percent slopes Ek Everett gravelly sandy loam, 15-30 percent slopes Ld Lystalr sandy loam, 0-5 percent slopes Go Gravel pit Le Lystalr sandy loam, 5-15 percent slopes GD Grove cobbly sandy Igsm, 0-5 percent slopes Lf Lystalr sandy loom,15.30 percent slopes Gc Grove cobbly sandy loam, 5-15 percent slopes Me Made land GA Grove cobbly sandy loam, 15.30 percent slopes Mb Maytown silt loom,0-3 percent slopes Go Grove gravelly loam, 0.5 percent slopes Mc McKenna gravelly foam, 0-3 percent slopes Gf Grove gravelly loam, 5.15 percent slopes Md McKenna loam, 0-3 percent slopes Go Grove gravelly loam, basin phase, 0.5 percent slopes Me McMurray peat, 0-2 percent slopes Gh Grove gravelly sandy loom, 0-5 percent slopes Mf McMurray peat, shallow over gravel, 0.2 percent slopes Gk Grove gravelly asndy loam, 5-15 percent slopes Mg Mukilteo peat, 0.2 percent scopes Gm Grove gravelly sandy loam, 15.30 percent slopes Mh Mukilteo peat shallow over gravel, 0-2 percent slopes Gn Grove gravelly sandy loam, 30-45 percent slopes l gravelly No Nose loam, 0 5 percent slopes Go Grove gravelly sandy loam, basin phase, 0-5 percent slopes Nb Nasaby loam, loo percent slopes GI) Grow stony sandy loam, 0-5 percent slopes I by R. H. Fowler and R. G. Parvin, nl Experiment Station, and A. 0. Ness, Agriculture. Roberts, U. S. Department of Agriculture. APPENDIX B BASIN MAPS Post Developed Basin Map 131 v ' o `g E �--- W Fil 41 ------------- 4,:o � O � Y � i APPENDIX C BASIN RUNOFF CALCULATIONS & DESIGN Isopluvial Maps 2—YR 24-HR Cl 10-YR 24-HR C2 100 -YR 24-HR C3 SCS Curve Numbers C4 Infiltration Values C5 Hydrology Calculations C6-C7 I • • Sy .l t�v„� I •" RM .�...- ��r Toll •.I .••• i�.•�,�'�„ I IV IN T trm - 66 / • 1 ' •t M • j 1 •. � ` � r .�����'�`1` I• ���.If.,,�'�""^ gal N WA --,$•may �: � I �•�►'* c�.�_ OL All S ' �;1�� T�T A•lam� r� 1'! T fir• � � .� STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN Table III-1.3 SCS Western Washington Runoff Curve Numbers (Published by SCS in 1982) Runoff curve numbers for selected agricultural, suburban and urban land use for Type lA rainfall distribution, 24-hour storm duration. LAND USE DESCRIPTION CURVE NUMBERS BY HYDROLOGIC SOIL GROUP A B C D Cultivated land(1) : winter condition 86 91 94 95 Mountain open areas: low growing brush & grasslands 74 82 89 92 Meadow or pasture: 65 78 85 89 Wood or forest land: undisturbed 42 64 76 81 Wood or forest land: young second growth or brush 55 72 81 86 Orchard: with cover crop81 88 92 94 Open spaces, lawns, parks, golf courses, cemeteries, landscaping. Good condition: grass cover on z758 of the 68 80 86 90 area Fair condition: grass cover on 50-75% of 77 85 90 92 the area Gravel roads & parking lots: 76 85 89 91 Dirt roads & parking lots: 72 82 87 89 Impervious surfaces, pavement, roofs etc. 98 98 98 98 Open water bodies: lakes, wetlands, 12onds etc. 100 100 100 100 Single family residential(2) : Dwelling Unit/Gross Acre %Impervious(3) Separate curve number 1.0 DU/GA 15 shall be selected for 1.5 DU/GA 20 pervious & impervious 2.0 DU/GA 25 portions of the site 2.5 DU/GA 30 or basin 3.0 DU/GA 34 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 PUD' s, condos, apartments, %impervious commercial businesses & must be industrial areas computed (1) For a more detailed description of a ricultural land use c refer to National Engineering Handbook, Sec. 4, Hydrology, Chapterv9,numbers A gust 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. IIZ-1-12 FEBRUARY, 1992 � 4- H tD H Infiltration Cation Exchange Effective H y Texture Rate Capacity Water Capacity Hydrologic I � Class Hydrologic (milliequivalentg/ (inches per Soil Group '' U (inchealhr.) 100 grams) inch) z Coarse Sands or Cobbles 20.00 <5.0 - A 0 > r• � Sand `6.27 <5.0 0.35 A r Loamy Sand 2.41 5.0 0.31 A H M H Sandy Loam 1.02 >5.0 0.25 B h w IrtC: Loam 0.52 >5.0 0.19 B M CO to Silt Loam 0.27 >5.0 0.17 C n r �y Sandy Clay Loam 0.17 >5.0 0.14 C m H � x Clay Loam 0.09 >5.0 0.14 D M tzj Silty Clay Loam 0.06 >5.0 0.11 D 0 C: C7 Sandy Clay 0.05 >5.0 0.09 D H to � Silty Clay 0.04 >5.0 0.09 D 0 [ ~' z Clay 0.02 >5.0 0.08 D r 0 H � M y Source(except for cation exchange capacity): Rawls, Brakensiek,and Saxton, 1982(16) rt X to z CCation exchange capacity values are estimated from Buckman and Brady, 1969,(23) r kD N RICHARD EGER WORKSHOP ROY BOAD ROAD, BELFAIR t i Y D ROLOGY CALCULATIONS PRECIPITATION: Event Precip (in) ..................... 6 month 2.4000 2 year 3.6000 10 year 4.8000 100 year µ6.8000 BASIN ID• DE Design Method SBUH Rainfall type TYPEIA Hyd Intv 10.00 min ;Peaking Factor 484.00 1 Abstraction Coeff 0.20 Pervious Area 0.00 ac DCIA 0.33 ac Pervious CN 0.00 DC CN 98.0071-11 _ _ ............ .. .........._., _ ..... ;Pervious TC 0.00 min IDC TC. 6.00 min ..._.. .. _.._ _ ...._......_._ .. _ ......._......-. ectly Description lrConnected CN Cale ......._ _. ... ........_........ _....... SubA rea , Sub cn ...............__. .... ........... _....... _.. ..._ Impervious surfaces (pavements,roofs, etc) 0.33 ac 98.00 :...-- ..._...._................ . . DC Com osited CN2 98 00 p (AMC( ) i _.... _. ...__ ......... ...._.. - _ _. _. Directly Connected TC Cale _ .----- _ . _....__. .. j Type Description Length Slope Coeff Misc TT __. '.Fixed MINIMUM I 6.00 min __.......... _.. ..__.......___._. Directly Connected TC 6.00min ___ ____-.._ _- ._.__._ .�.�__._________.__._ j EVENT SUMMARY: Event Peak Q Peak T Peak Vol(ac- Area BasinID 1 'Method/Loss Raintype - 24 hour (cfs) (hrs) cf) (ac) _..................... .... ..... .......-.._ .. ..............j .. ......._ {........ ...... _._.._..._ _..._ DE 6-month 0.1766 8.000.0597 0.33 SBUH/SCS TYPEIA DE 2-year 0.2699 8.00 0.0926 0.33 ISBUH/SCS TYPEIA ... ..........._. .__....._ _......,_.. -- --...._..... ... DE 10-yeaz 0.3625 :8.00 10.1255 ;0.33 SBUH/SCS TYPElA ......_.._....................._........._.................._.............__............- _................._......._._..._.._................._..............................-.............. ................. ..... . DE 100-yeaz 0.5161 8.00 0.1804 10.33 SBUH/SCS TYPEIA ........-.........._...._...._._ ......._ i li C6 i RICHARD EGER WORKSHOP ROY BOAD ROAD, BELFAIR HYDROLOGY CALCULATIONS STORAGE ID: TRENCH-AS-VAULT Descrip: Storage of Infiltration Trench Increment 0.10 ft Start El. 71.0000 ft Max El. 74.0000 ft Length 40.0000 ft Width 20.0000 ft Catch 30.0000 Stage Storage Rating Curve 71.0000 ft 0.0000 cf 72.6000 ft 384.0000 cf 71.1000 ft 24.0000 cf 72.7000 ft 408.0000 cf 71.2000 ft 48.0000 cf 72.8000 ft 432.0000 cf 71.3000 ft 72.0000 cf 72.9000 ft 456.0000 cf 71.4000 ft 96.0000 cf '73.0000 ft 480.0000 cf 71.5000 ft 120.0000 cf 73.1000 ft 504.0000 cf 71.6000 ft 144.0000 cf 73.2000 ft 528.0000 cf 71.7000 ft 168.0000 cf 73.3000 ft 552.0000 cf 71.8000 ft 192.0000 cf 73.4000 ft 576.0000 cf 71.9000 ft 216.0000 cf 73.5000 ft 600.0000 cf 72.0000 ft'240.0000 cf 73.6000 ft 624.0000 cf ....... ... 72.1000 ft 264.0000 cf 73.7000 ft 648.0000 cf 72.2000 ft 288.0000 cf 73.8000 ft 672.0000 cf 72.3000 ft 312.0000 cf 73.9000 ft 696.0000 cf 72.4000 ft 336.0000 cf 74.0000 ft 720.0000 cf 72.5000 ft 360.0000 cf 74.1000 ft 744.0000 cf C7 RICHARD EGER WORKSHOP ROY BOAD ROAD, BELFAIR HYDROLOGY CALCULATIONS DISCHARGE ID: TRENCH-DISCHARGE Descrip: Infiltration Discharge Increment 0.10 ft Start El. 71.0000 ft Max El. 74.0000 ft Stage (ft) Discharge (cfs) 71.00 0.0000 71.01 0.1850 71.50 0.1940 72.00 0.2040 72.50 0.2130 73.00 0.2220 73.50 0.2310 74.00 0.2410 Stage Discharge Rating Curve 71.0000 ft 0.0000 cfs 72.6000 ft 0.2148 cfs 71.1000 ft '0.1867 cfs '72.7000 ft 0.2166 cfs 71.2000 ft;0.1885 cfs 72.8000 ft 0.2184 cfs 71.3000 ft 0.1903 cfs 72..9000 ft 0.2202 cfs 71.4000 ft'0.1922 cfs 73.0000 ft 0.2220 cfs 71.5000 ft '0.1940 cfs 73.1000 ft 0.2238 cfs 71.6000 ft 0.1960 cfs '73.2000 ft 0.2256 cfs 71.7000 ft'0.1980 cfs 73.3000 ft 0.2274 cfs 71.8000 ft'0.2000 cfs 73.4000 ft 0.2292 cfs 71.9000 ft,0.2020 cfs 73.5000 ft 0.2310 cfs' 72.0000 ft 0.2040 cfs 73.6000 ft 0.2330 cfs'' 72.1000 ft 0.2058 cfs 73.7000 ft 0.2350 cfs' 72.2000 ft 0.2076 cfs 73.8000 ft 0.2370 cfs' 72.3000 ft '0.2094 cfs 73.9000 ft 0.2390 cfs 72.4000 ft 0.2112 cfs 74.0000 ft 0.2410 cfs'. 72.5000 ft I0.2130 cfs 74.1000 ft 0.2410 cfs 74.000Oft 0.2410 cfs' C8 RICHARD EGER WORKSHOP ROY BOAD ROAD, BELFAIR HYDROLOGY CALCULATIONS ROUTING ID: LEVEL-POOL 'Descrip: Level Pool Routing Increment 0.10 ft Start El. 71.0000 ft Max El. 74.0000 ft .Storage Node TRENCH-AS-VAULT Discharge Node TRENCH-DISCHARGE LEVEL-POOL SUMMARY using Puls Event Match Q Peak Q Peak Stg Peak Stg Vol Vol Time to (cfs) (cfs) (ft) (elevation) (cf) (acft) Empty _ _..._._ ._ _ 6 month 0.1766 0.1790 0.0959 71.10 23.01 0.0005 24.50 . 2 year 0.2699 0.1941 0.5034 71.50 120.81 0.0028 24.67 _, ......... _ _. .. 10 year 0.3625 0.2067 1.1496 72.15 275.91 ' 0.0063 24.67 _ 100 year 0.5161 ' 0.2311 2.5055 73.51 601.32' 0.0138 24.67 _ . ............. . .... OUTFALL HYDROGRAPH SUMMARY HydID [Peak Q (cfs) Peak T (hrs) Peak Vol(ac-ft) Cont Area (ac)' ..._._.. 6 month out '0.18 8.00 0.0597 0.3300 2 year out 0.19 8.17 0.0926 0.3300 _ _ 10 year out 0.21 8.33 0.1255 0.3300 100 year out!0.23 8.67 0.1804 0.3300 I C9 304-trench.xls PROJECT: RICHARD EGER WORKSHOP FILE: I CIV/LENG13041 STORM1304-TRENCH.XLS DEPT. OF ECOLGY, STORMWATER MGT. MANUAL - PUGET SOUND REGION SECTION III-3.4 INFILTRATION POND CALCULATION VARIABLES: Gravel USDA SOIL CLASSIFICATION 3.00 min/inch (F) PERMEABILITY RATE 20.00 inch/hour 2 (d) PERC RATE SAFETY FACTOR ("2" RECOMMENDED) 3.0 ft (h) MAX. HEIGHT OF STANDING WATER IN FACILITY loft (L) BOTTOM OF INFILTRATION MEDIA TO WATER TABLE/BEDROCK CALCULATED INFILTRATION FLOW: 0.83 ft/hour (Fd) PERC RATE (CONVERTED TO FEET PER HOUR) AND ADJUSTED BY SAFETY FACTOR SYSTEM PARAMETERS: 40.00 ft (X) BOTTOM LENGTH 20.00 ft (Y) BOTTOM WIDTH 0.00 :1 SIDE SLOPES 30% VOID RATIO FORMULA: Q = Fd * i *A where- i = (h+L)/L A=X*Y STAGE STORAGE AND DISCHARGE TRENCH GROSS NET NET h i AREA Q ELEV VOLUME VOLUME VOLUME (ft) (ft/ft) (so (cfs) (ft) (co (co (acre-ft) 0.0 1.0 800 0.185 71.00 0 0 0.00 0.5 1.1 800 0.194 71.50 400 120 0.00 1.0 1.1 800 0.204 72.00 800 240 0.01 1.5 1.2 800 0.213 72.50 1200 360 0.01 2.0 1.2 800 0.222 73.00 1600 480 0.01 2.5 1.3 800 0.231 73.50 2000 600 0.01 3.0 1.3 800 0.241 74.00 2400 720 0.02 C10 APPENDIX D WATER QUALITY CALCULATIONS Biofiltration Swale Design D2 &D3 i i i i 6 . /V�(-) .SL,)GIe TRAPEZOIDAL CHANNEL ANALYSIS RATING CURVE COMPUTATION March 17, 2004 PROGRAM INPUT DATA DESCRIPTION VALUE -------------------------------------------------------------------------------- Channel Bottom Slope (ft/ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.055 Manning's Roughness Coefficient (n-value) . .. . . . . . . . .. . . . . . .. 0.08 Channel Left Side Slope (horizontal/vertical) . . . . . . . . . . . . ... 3.0 Channel Right Side Slope (horizontal/vertical) . .. . . .. . .. . . .. 3.0 Channel Bottom Width (ft) . . . . .. . .... . . . . . .. . . . . . . . . . . . . . . . . . 2.0 Minimum Flow Depth (ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 Maximum Flow Depth (ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Incremental Head (ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 ------------ COMPUTATION RESULTS Flow Flow Flow Froude Velocity Energy Flow Top Depth Rate Velocity Number Head Head Area Width (ft) (cfs) (fps) (ft) (ft) (sq ft) (ft) -------------------------------------------------------------------------------- _.� 0.1 0.2 0.86 0.508 0.011 0.111 0.23 2.6 F- 0.2 0.67 1.28 0.56 0.025 0.225 0.52 3.2 0.3 1.39 1.6 0.591 0.04 0.34 0.87 3.8 0A 2.4 1.88 0.613 0.055 0.455 1.28 4.4 0.5 3.71 2.12 0.631 0.07 0.57 1.75 5.0 0.6 5.33 2.34 0.646 0.085 0.685 2.28 5.6 0.7 7.3 2.54 0.659 0.101 0.801 2.87 6.2 0.8 9.64 2.74 0.671 0.117 0.917 3.52 6.8 0.9 12.37 2.92 0.682 0.133 1.033 4.23 7.4 1.0 15.5 3.1 0.691 0.149 1.149 5.0 8.0 1.1 19.07 3.27 0.701 0.166 1.266 5.83 8.6 HYDROCALC Hydraulics for Windows, Version 1.2a Copyright (c) 1996 Dodson & Associates, Inc., 5629 FM 1960 West, Suite 314, Houston, TX 77069 Phone: (281)440-3787, Fax: (281)440-4742, Email:software@dodson-hydro.com All Rights Reserved. I I I r_ i I i I I I I i I i i i I i I�, • 100 y r .S w (21 1 (� TRAPEZOIDAL CHANNEL ANALYSIS RATING CURVE COMPUTATION March 17, 2004 PROGRAM INPUT DATA DESCRIPTION VALUE -------------------------------------------------------------------------------- Channel Bottom Slope (ft/ft) . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.055 Manning's Roughness Coefficient (n-value) . . . . . . . . . . . . . . . . . . . 0.025 Channel Left Side Slope (horizontal/vertical) .. .. . . . . . . . . . . . 3.0 Channel Right Side Slope (horizontal/vertical) . . . . . . . . . . . . . . 3.0 Channel Bottom Width (ft) . . . . ... . . . . . . .. . . . . . . . . . . . . . . . . . . . . 2.0 Minimum Flow Depth (ft) . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 Maximum Flow Depth (ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Incremental Head (ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 COMPUTATION RESULTS Flow Flow Flow Froude Velocity Energy Flow Top Depth Rate Velocity Number Head Head Area Width (ft) (cfs) (fps) (ft) (ft) (sq ft) (ft) -------------------------------------------------------------------------------- '� 0.1 0.63 2.74 1.627 0.117 0.217 0.23 2.6 0.2 2.13 4.1 1.791 0.261 0.461 0.52 3.2 0.3 4.46 5.13 1.89 0.409 0.709 0.87 3.8 0.4 7.68 6.0 1.962 0.56 0.96 1.28 4.4 0.5 11.86 6.78 2.019 0.714 1.214 1.75 5.0 0.6 17.06 7.48 2.068 0.671 1.471 2.28 5.6 0.7 23.37 8.14 2.11 1.031 1.731 2.87 6.2 0.8 30.85 8.76 2.148 1.194 1.994 3.52 6.8 0.9 39.58 9.36 2.182 1.36 2.26 4.23 7.4 1.0 49.61 9.92 2.213 1.53 2.53 5.0 8.0 1.1 61.03 10.47 2.242 1.703 2.803 5.83 8.6 HYDROCALC Hydraulics for Windows, Version 1.2a Copyright (c) 1996 Dodson & Associates, Inc., 5629 FM 1960 West, Suite 314, Houston, TX 77069 Phone: (281)440-3787, Fax: (281)440-4742, Email:software@dodson-hydro.com All Rights Reserved. l00 YO I'