Loading...
07-0276 Storm Drainage Report 042908 001STORM DRAINAGE REPORT Yelm RV/Boat &Mini-Storage Between Crystal Springs Road S.E. and Rhoton Road S.E. Yelm, Washington Prepared for: Randy Weber 25720 - 21 7th Avenue S.E. Maple Valley, WA 98038 April 24, 2008 Our Job No. 12433 GHAT ~' ~-/ S'~ m ~, Z n `~ u 0 2 <r~ eke ~r' ENG~N CIVIL ENGINEERING, LAND PLANNING, SURVEYING, ENVIRONMENTAL SERVICES 18215 72ND AVENUE SOUTH KENT, WA 98032 (425) 251-6222 (425) 251-8782 FAX BRANCH OFFICES • OLYMPIA, WA • TACOMA, WA • SACRAMENTO, CA • TEMECULA, CA www.barghausen.com RECEIVE D APR 2 8 1008 I 1 TABLE OF CONTENTS 1.0 PROJECT OVERVIEW Figure 1 -Vicinity Map Figure 2 -Soils Map 2.0 EXISTING CONDITIONS SUMMARY ANU ANALYSIS OF REQUIREMENTS 2.1 Analysis of the Minimum Requirements 3.0 OFF-SITE ANALYSIS 3.1 Study Area Definition 3.2 Upstream Drainage Analysis 3.3 Field Inspection 4.0 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND llESIGN A. Existing Sitc Hydrology B. Developed Site Hydrology C. Performance Standards D. Flow Control System E. Water Quality System F. Conveyance System Analysis and Design 5.0 CONSTRUCTION STORMWAT'LR POLLUTION PREVENTION PLAN 6.0 SPECIAL REPOR"TS AND STUDIES 7.0 OTHER PERMITS 8.0 OPERATIONS AND MA[N1'ENANCE MANUAL 9.0 BOND QUANTITIES l 2433.003.doc I.0 PKOJECT OVERVIEW The proposed Yelm RV/Boat &Mini-Storage development has a gross site area of 7.57 acres located in a portion of the Northwest quarter of Section 19, Township 17 North, Range 2 East, Willamette Meridian, City of Yelm, Washington. More specifically, the project is located west of Rhoton Road S.E. and to the east of Crystal Springs Road. Please refer to the vicinity snap (Figure 1) for a more accurate depiction of the project location. "I'he proposed Yelm RV/Boat &Mini-Storage project proposes to construct 8 storage buildings and an associated office building totaling 72,590 SP. The development will include RV parking spaces on the south and west sides of the site. The project proposes to infiltrate the stormwater runoff through a pervious asphalt paving section. The pervious asphalt will provide a media for the stormwater to filter and infiltrate into the existing ground. All stormwater facilities will be designed in accordance with the City of Yelm and the 1992 Department of Ecology Stonnwatcr Management Manual. 12433.003.doc FIGURE 1 VICINITY MAP i ~` l \ ~.. _4 \ U SE ' ~ ;~ , ~ ~ • ~; ~ ~~ W SE ~I E ~I ' I 6 ~A?~.. ~s ~~a . , s? Z, A ~~ ,l Y ti ~vstwu r ~ r.~etr m~ ~/ w ~ Cf a. ' ~ pp~ t n( "~~% i I~~~a ~ /~/~ ~p4tx` Av g ~~• ~ ~~~~ B _ ~ . ,M i REFERENCE: Thomas Guide (2006) Mlttr E~ ~E C7 SE i-^ Honzontel: N.T.S. VetiCal: N/A ~,G H A V S 18215 72ND AVENUE SOUTH ~ ~• ~1- KENT, WA 98032 m - ~ Z (425) 251-6222 o ~ (425) 251-8782 s ~ ~<r ~p~ ~' ~ CNIL ENGINEERING, LAND PLANNING, ~~ eNa\N SURVEYING, ENVIRONMENTAL SERVICES ~, c E - ~ t~ R ~ ar;.'~. ~, ti~.~ y~~.;' ~ ,.dam ~ „.: ~c ;=7L ~~_ ~ uw. F \ A ~ 2 ~ ~Q \ /~~ u SE` i iolon ~ ~~ ~~ u " ~g ~0 ~= G ft's ~, H Q ~'~ f m I1QiM ' ,W SE E N $E 7L 7~.- ___ 1107M IM SE FOr• Job Number YELM RV/BOAT &MINI-STORAGE 12433 YELM, WASHINGTON Tale: VICINITY MAP DATE: 1 /25/08 2.U EXISTING CONUI`I'IONS SUMMAKY ANU ANALYSIS OF KEQUIKEMENTS 2.1 Analysis of Minimum Kequirements Minimum Requirement No. 1: Preparation of Storm Drainage Report. Response: This Storm Drainage Report has been prepared in accordance with the 1992 Washington State Department of Ecology (UOL') Stonnwater Management Manual for the Puget Sound Basin. Minimum Requirement No. Z: Constnrction Stormwater Pollution Prevention (SWPP). Response: A SWPP Plan is not required since the project proposes to infiltrate all Stonnwater from the site. Minimum Requirement No. 3: Source Control of Pollution. Response: There are no required source controls for this project. Minimum Requirement No. 4: Preservation of Natural Drainage Systems and Outfalls. Response: The stonnwater Gom the site will be infiltrated on site as in the pre-existing condition. Minimum Requirement No. S: On-Site Stormwater Management. Response: A pervious asphalt pavement section has been designed to infiltrate the 100- year developed storm. Minimum Requirement No. 6: Runoff "Treatment. Response: A 12-inch Water Quality Treatment layer has been incorporated in the previous asphalt pavement section to provide treatment before discharging into the existing ground. Minimum Requirement No. 7: Flow Control. Response: This project proposes a pervious pavement section that will retain and infiltrate Stormwater runoff in accordance with the 1992 Stormwater Management Manual for the Puget Sound Basin methodology. Minimum Requirement No. 8: Wetlands Protection. Response: There are no wetlands on the development, but there is Yelm Creek along the west property line with a 200-foot buffer. Minimum Requirement No. 9: Basin/6f'atershed Planning. Response: No special basin/watershed planning is necessary for the site. ' 12433.003.doc Minimum Requirement No. 10: Operation and Maintenance. ~ Response: An operation and maintenance manual consistent with the provisions in 1992 Stonnwater Management Manual for the Puget Sound Basin will be provided for all proposed stonnwater facilities and BMPs. '' 12433.003.doc FIGURE 2 SOILS MAP Scare: /-pr' Job Number Horizontal: N.T.S. Vertical: WA YELM RV/BOAT &MINI-STORAGE 12433 GHAV 1821572ND AVENUE SOUTH YELM, WASHINGTON ~ ~-/ Stn KENT, WA 98032 m y Z (425) 251-6222 Tale: n J ~ Z (a25~ 251-s7s2 THURSTON COUNTY ~ijV- `~T~~'c~N~~H~6~+ SURVEYGNGEENVIRONMENTPAISEIRVICES SOIL SURVEY MAP DATE:1/25/oa soiLcd~ REFERENCE: USDA, Natural Resources Conservation Service LEGEND: 65 =McKenna gravelly silt loam, 0-5% slopes 110 = Spanaway gravelly sandy loam, 0-3% slopes 113 = Spanaway stony sandy loam, 3-15% slopes 3.0 OFF-SITE ANALYSIS 3.1 Study Area Definition The enclosed Figure 1 (Vicinity Map) shows the location of the proposed development. The site has relatively moderate slopes with a high point near the center of the site. Stormwater on the eastern portion of the site drains eastward into a ditch on 1Zhoton Road S.F,. Stormwater on the Western portion of the site drains to Yelm Creek, which is located approximately 250 feet west of the proposed development area. 3.2 Upstream Drainage Analysis Based on the site visit, there is very little upstream drainage onto the site. Runoff from the east is captured in the existing ditch on Rhoton Road S.l;., and the upstream runoff, if any, from the south and west is captured in Yelm Creek. 3.3 Field Inspection There were no problems that were reported or observed during inspection of the site. Based on the site investigation and general knowledge of the area, there is no known erosion or flooding problems that will occur, or be aggravated as a result of this development. 1 (2433.003.doc FIGURE 3 ASSESSOR MAP ttrr ccv t ~u ~ ~ ~ r ` \1 I'' \~~ r\~\ I'' i ~ M U AI ARE CO RT ^ 2 1.~ Ali 2 1n ~2 56M0' $.~OOSZi: ~ ~ .... ~ ~ I 210700 1 r 270300» J ,~ :,oP.+ 210 ~- ---- - i 220103 210600 ~ SS008255YL ~, KERS ADDITION , ' ~ ( 3 Q` 210800 i ' ~ `' 8203 ..,.,~ o. ~ `~ ~\ •\ 5 j ` ~ 6 y ~ G MCI :L- f ~•~0 4 / 220600 ~ ~' (~, I ~ 1)204 ~% a~ 210403 1 i ~ ~ ~"-"' 210404 ~ +~ ' 1,P ,,., ~ -- \ 220700 ' " 220205 ~ '~ ~_ ` ~] N e ~ _ ~ 5 e 2ao2oa ~~ ~E ~ alT t[7 A , CT -- ' ~/ ' ,230205 ~ 240101 tLtq]t ! , 5 ~ , 240100 ,~ 230400 \° ~~ / ~', ~ ~'` s~ _ ~ SITE 2ao2o3 ~~ /~` ` . ~' ~ 24021)0 240201 r\ ~ • ~ ` i ~i ~~'; ~'~ 230100 240202 / ~~ ~/ ~ ~020~ ~ ~'~ .~ ~- • ~y~~ ~ ~~ `. / O~~ ~ a , I/ ~ Sr maaa ~ i O~ ,-,~ i ,V\ ~ 231201 2so,ot ~~~~ `~~\ 240300 / ~J / ~ ~~ ,~~ , ~ / ti ~ ~ %" `~ y., ~~ MC KENNA IRRIGP \ 231200 240600 ~ \ ~ I - ~ ~~ 240500 /~ ~I _sao.~ ~ ~ ~ , ~ ' ~~ \. / : ~ . , ~ %~ ,~ 310200 ~ ~ - - - - - - - - - - fwLw~w Ro ,q~ %~ ~ ~~~~ ~~ ,o ~ ~ . ~~ $ *~ j ~ ~ „5 310300 F ~, SS028304 ~\' x~y /`~ ,~/, ~Q~,a~FC / 00500 stdo] ~" is ~ ~ a g ~` ,~., t ~,: 5oopp7~ ~\/ ~ ,~nc~7' qs~ ~ ~ ~ /' Q .6oeoo ~. ' i~4L ( 5t~ / S ' '~ ~v ' ~!0 ~ ~ ~~ % ~ ~ t9 4F'~ 200 ~ . ~ M tq~l ~~ n / E j ~ ` V - . ~ ]10805 ~`N 1 ~~ i ` ~\ / _ ~ ~ \ /~ \~' S _ .</ f ~ ~~ 00]00 ", r 6 ~4 ~~ ~. \ \ ~ ~ ° ~ y V T . ~ ~~ ~ / ~ ~\ ~ REFERENCE: Thurston, Washington Map ID: 17-2E-19 Scale: FOr' Job Number Horizontal: N.T.S. Vertical: WA YELM RV/BOAT &MINI-STORAGE 12433 ' Q,GHA vs 18215 72ND AVENUE SOUTH YELM, WASHINGTON Q- ~-- ~ KENT, WA 98032 m, ~ Z (425) 251-6222 Tjt~e. Z' - ~ (425) 251-8782 ASSESSOR MAP ~<r~J~ 6p~ CIVIL ENGINEERING, LAND PLANNING, rho ~NaSM~' SURVEYING, ENVIRONMENTAL SERVICES DATE: 1/25/0$ ' P:112000s11?4331exhibitlstorm drainage112433 amap.cdr FIGURE 4 FEMA MAP LEGEND ® FLOODWAY AREAS-IN ZONE AE OTHER fIOOD AREAS ST ~ ZONE X Area 4500-year flood; areas of /0p-year ~~ flood with average depths of less than 1 foot a ~' with drainage area less than 1 sgwre mile; ~~ ~,i~~` a~~ as protected by levees hom 100-year ~fF ~ ('~ OTHER AREAS L~ ZONE X ArendeterminedtobeouaideS00yerflood- sr'~ `tln :~'~' plain. REFERENCE: Federal Emergency Management Agency (Portion of map 530310 0001 A -June, 1999) ~: rOl:' Job Number HorizonfaL- N.T.S. Vertical: IIVA YELM RV/BOAT &MINI-STORAGE 12433 ~'HA V 18215 72ND AVENUE SOUTH YELM, WASHINGTON ~ ~-/ S~ KENT, WA 98032 m; J ~Z (425) 251-6222 Title: ~~ '~ (425) 251-8782 FEMA MAP °< , V e~~ CNIL ENGINEERING, LAND PLANNING, r~Na [HO~N~'6 SURVEYING, ENVIRONMENTAL SERVICES DATE: 1/25/08 FIGURE 5 TOPOGRAPHIC MAP _ _. _. 13 ~O y C Scale: F-Q/;' Job Number Horfzontal: N.T.S. Vertical: wA YELM RV/BOAT &MINI-STORAGE 12433 GHA V 18215 72NDAVENUE SOUTH YELM, WASHINGTON ~ ~-/ Stn KENT, WA 98032 Q1 - J=~Z (425) 251-6222 Tlt~@: 3 (425)251-8782 TOPOGRAPHIC MAP 1 '" ? ~o`rv~U~ `e' CML ENGINEERING, LAND PLANNING, 'NO cwa~e~ SURVEYING, ENVIRONMENTAL SERVICES DATE: 1/25/0$ R REFERENCE: www.topo.com (2006) FIGURE 6 C SENSITNE AREAS MAP e P -yT •- ~c r ~~. `s~pol ~ .`'~ ~ `~ `~R CIS t r =r. i .r - _ .~~' .^~ . J ~ - ~. ^-t ~ ~ ~ i~. ~~~ ~ . ~. R~ [.ELM ~.~. - . ~ - ~ ~ ti• • ~ '~~ 4 ~ ~ ~~. .~:~ ` . 1' a~ ~~ 1 ~~~ ~ 'I',~ ~~ ~ ' , Roads ` . ~ ~" ~ ~ ~''~ ~ ` Streams ~~ ~ ` ~~` '~ Water Bodies Wettand ~.- . s r ~. , ~~ 2005 Aerial Pholos REFERENCE: Thurston County Map kale: Horizontal: N.T.S. Ven9cal: WA GH A V S ~ 18215 72ND AVENUE SOUTH ~ ~-/ ~ KENT, WA 98032 Z Q1 ~ (425) 251-6222 ~ o a (425) 251-8782 _ z = ~< ~ r°~ r~ ~ CIVIL ENGINEERING, LAND PLANNING, ~'c tNa~N~' SURVEYING, ENVIRONMENTAL SERVICES YELM RV/BOAT &MINI-STORAGE 12433 YELM, WASHINGTON Title: SENSITIVE AREAS MAP DATE: 1/25/08 4.0 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN A. Existing Site Iydrology The site is currently covered with pasture and trees. 1'he site has relatively moderate slopes on the developable portion of the site ranging from 0 to 3 percent. The site has a high point near the center of the site. Stormwater on the eastern portion of the site drains eastward into an existing ditch on Rhoton Koad S.E. Stormwater on the western portion of the site drains to Yelrn Creek. I3. Developed Site Hydrology Stormwater from the entire developable portion of the site will be infiltrated through the proposed pervious asphalt pavement section. Roof drains with splash blocks will be placed at maximum every 50' along each building. The splash block will allow the water to distribute on the pervious asphalt and infiltrate into the existing ground. C. Performance Standards The 100-year developed storm event will be infiltrated on site in a 24-hour period through the proposed pervious asphalt pavement section. ll. Flow Control System The developed 100-year storm event will be infiltrated on site through the proposed pervious asphalt pavement section. E. Water Quality System As part of the pervious asphalt pavement section, a 12-inch minimum water quality treatment layer has been proposed. This layer will consist of WSDOT 9-03.13, Backfill for sand drains that will help to filter out pollutants. F. Conveyance System Analysis and Design Surface runoff from the site will be captured in the pervious asphalt pavement section. Runoff from the roof drains will be directly discharged onto splash blocks that will distribute the runoff onto the pervious asphalt pavement and ultimately into the existing ground. There are no catch basins or conveyance pipes proposed for this project. ~ ~d33-003.doc 1 Q~G 1 Vl 1 Appended on: 09:46:42 Monday, )vlarch 31, 2008 12433dev Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd ~~ol (acft) Area (ac) 1\9ethod Raintype 2 year 1.28(8 7.83 0.4492 4.4446 SBUH TYPEIA 5 year 1.7919 7.83 0.(091 4.4446 SBUH TYPE 1 A 10 year 2.3202 7.83 0.7748 4.4446 SBUH TYPE 1 A 25 year 2.8639 7.83 0.9445 4.4446 SBUH TYPE 1.A l0U year 3.5300 7.83 1.1 ~ 18 -1 -4-i-1~~ ~I31 it I TYP11 A Record Id: 12433dev Design Ivlethod SBUH Rainfall type TYPElA >Elvd Inty 10.00 min Peaking Factor 484.00 Abstraction Coeff 0.20 Pervious Area 2.55 ac llCIA 1.89 ac Pervious CN 8.00 DC CN 98.00 Pervious TC 2.02 min llC TC 2.02 min Pervious CN Calc Description SubArea Sub cn Gravel Roads & Parking Lots 2.06 ac 85.00 Golf crse/cemeteries/landscaping (50-75% grass) 0.49 ac 85.00 Pervious Composited CN (AMC 2) 85.00 Pervious TC Calc Type Description Length Slope Sheet Smooth Surfaces.: 0.01 1 100.00 ft 1.00% Coeff IV1isc TT 0.01 10 2.00 in 2.02 min Pervious TC 2.02 min Directly Connected CN Cale Description SubArea Sub cn Impervious surfaces (pavements, roofs, etc) l .89 ac 98.00 DC Composited CN (AMC 2) 98.00 Directl~~ Connected TC Calc Type Description Length Slope Sheet Smooth Surfaces.: 0.011 100.00 ft 1.00%, Coeff 1\~isc TT 0.0110 2.00 in 2.02 min Directly Connected "I'C 2.02min Licensed to: Barghausen Engineers file://P:\ 12000s\12433\engineering\StormShed\ 12503-tesc.html 3/31 /2008