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Report .StT2019-00013 1)-090 s J A11 4-0J 5r BA GURUS EN RECEIVED MAY 6 2019 CITY OF TIBC BUILDING DIVISICO STORMWATER MANAGEMENT REPORT McDonald's ADA Improvements X09`4 12090 SW Main St. ON Tigard, OR 97223 Prepared for: Freiheit Architecture 929 108th Avenue NE, Suite 210 Bellevue, WA 98004 Engineer of Record: Chris Jensen, PE Barghausen Consulting Engineers, Inc. 18215 - 72nd Avenue S. ���0 PROFFS Kent, WA 98032 s (425) 251 -6222 , -,,,-/ < C). , c ensen bar hausen.com r r cti�t� q -J,ASC 4/25/19 April 25, 2019 { *J Our Job No. 20604 BARGHAUSEN CONSULTING ENGINEERS, INC. 1821572ND AVENUE SOUTH KENT,WA 98032 P)425-251-6222 F)425-251-8782 BRANCH OFFICES: TUMWATER,WA KLAMATH FALLS,OP LONG BEACH,CA ROSEVILLE,CA SAN DIEGO,CA barghause n.com DESIGNERS CERTIFICATION AND STATEMENT I hereby certify that this Stormwater Management Report for McDonald's SW Main St.ADA Improvements has been prepared by me or under my supervision and meets minimum standards of the City of Tigard and normal standards of engineering practice.I hereby acknowledge and agree that the jurisdiction does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities designed by me. ��gED pRpFFSce S G;MI- <0), , c. OREGON i4 2C,)< yR/S R.J�\ASF. 4/25/19 EXPIRES: 6-30—'9 TABLE OF CONTENTS 1.0 PROJECT OVERVIEW AND DESCRIPTION 2.0 METHODOLOGY 3.0 ANALYSIS 4.0 ENGINEERING CONCLUSIONS 5.0 STORMWATER FACILITY DETAILS AND EXHIBITS 6.0 FINAL OPERATIONS AND MAINTENANCE (O&M) MANUAL AND O&M FORM 7.0 ADDITIONAL FORMS 8.0 ASSOCIATED REPORTS SUBMITTED EXHIBITS EXHIBIT A Vicinity Map EXHIBIT B Assessor's Map EXHIBIT C FEMA Map EXHIBIT D Soils Survey Map EXHIBIT E Existing Conditions Basin Map EXHIBIT F Water Quality Basin Area Map EXHIBIT G Stormfilter Standard Detail .:.. . ,. � ,- te; 4. atA f<\\ 4. ».\\ \\,, \\ ai44-::4'4.04 #40';'4'' \. \4\ 144, w\ , ''s.\ a , y3V \ ., gx ,r.- A ,, tey *\,,,,,44 � r*. „ vA„ , � ,- A F r,. .. �, a , y ,tygym.. r xl� „\. \a., c . .�. . - 's - . \A .f . ffi AeAAv, i, \ \ ,� � ,.4:1 -..3#4 AAA , : � '44N47,4.-----4-24,'r ». , AAAA -- 1"--:-'4-4-ager ....-,44t,44:-Is � s s - 2''k-'''''''''''',14.40:016,4,1‘.:' . , . A „ VyA v ,a \ r ..-., 4..,.-,-.-.;.:;. . a, :vR i� ,.. . 1\ \ „� " „A4. . �. .»... „ a0\A� \\a a1 , l.fi�, a1. 5 � \ A , � .. v,,wvvvvwy''''‘, 31-11*'''''''''''''''\ v , R ,: s „ ImN, .. . » . .\\q\\ \ � _�- , , �n ,. , \,. - �� ,�,, a v ,. � ..� � .�..,y .,a....� A\\\\ ��\\ .. ,�a .�� ��� O ■ 1.0 PROJECT OVERVIEW AND DESCRIPTION Size and Location of Project Site The project site is located at 12090 SW Main St. in the City of Tigard, Oregon. The generally rectangular parcel is 0.43 acres in size. Please refer to Exhibit A-E for the existing information. Type of Development/Proposed Improvements The project proposes to meet accessibility requirements via relocating ADA parking stalls, reconstructing sidewalks around the building perimeter and constructing an ADA path leading to the SW Scoffins St. right-of-way. Moreover, improvements in the drive-thru area include repaving the drive-thru, relocating the trash enclosure, and installing landscape. Topography The site is generally elevated at approximately 191 feet above mean sea level with existing slopes that range from 2-9%. The surface is largely covered with concrete and asphalt pavements, generally sloping down towards the south side of the property. Soils Soil maps from the Natural Resources Conservation Service(NRCS)were utilized to analyze the soil, conditions in the site vicinity. The existing near-surface soils near the site consist of Quatama loam sloped at 3 to 7 percent. Quatama loam generally has a moderately high hydraulic conductivity ranging from 0.2 to 0.57 inches per hour. The water table is mapped approximately between 24 to 36 inches below ground surface in the site vicinity. Hydrology The area of the site is located within the jurisdiction of Clean Water Services and is located in the Tualatin Watershed. The 712 square mile basin provides storage and releases water to Clean Water Services and a number of tributaries. Per FEMA Standards,the project is situated in a minimal hazard zone (Zone X). Vegetation & Habitat The proposed project has minimal vegetation with existing trees to remain around the perimeter of the site. Water Quality Sensitive Areas The proposed project site does not have any wetlands within the property or its vicinity. Property Zoning The project site is zoned General Commercial (C-G), per the Zoning and Comprehensive Plan of Tigard City. This zone permits the operations of restaurants and is designed to accommodate establishments with a city-wide trade area. Access The site has parking adjacent to an ingress/egress easement that borders the south and east boundaries with drive-thru ingress and egress via this easement as well. The proposed ADA path leading from the store to the SW Scoffins St right-of-way will be constructed on the southern portion of the building. 20604-001.docx Utility Availability and Conflicts No utilities are expected to be altered for the scope of this project. The contractor shall verify the locations of the existing utilities prior to construction. Site Analysis Permits Required Permits required for this project include a City of Tigard Site Work Permit. Existing vs. Post-Construction Conditions The existing site consists of an existing McDonald's Restaurant with associated concrete sidewalks, paved parking, patio dining area, and drive-thru. Landscaping surrounds the north and west site boundaries with planter strips and islands around the building. Please see the Existing Conditions Map located in Exhibit E for details of existing site conditions. Post-Construction includes the relocation of the ADA parking stalls, a repaved drive thru lane, a relocated trash enclosure, regraded sidewalks, added landscaping, and an accessible ramp system leading to the SW Scoffins St. right-of-way. Please see the Post-Developed Basin Map in Exhibit F. The project proposes to modify 7,807 square feet of impervious surface. The post-construction site impervious surface area will be less than the existing site impervious area by 202 square feet. 20604-001.docx Exhibit A14 q \ Vicinity map �/ ry 5 414 f y,� ;t• �,a � .P,. 4 >) !,.ii$icy :'r E, u rr v. F i 7~ tr, a S�"t 6 w \�a L,b.tertyPat k, SW N'''-r-'1 ..._..SITE sxt, 4 1'491,01 c.. r + REFERENCE: MapQuest.com (2019) Scale: For: Job Number Horizontal: N.T.S. Vertical: N/A McDonald's Remodel (Main St) 20604 ITIBarghausen Tigard, Oregon Consulting Engineers, Inc. 18215 72nd Avenue South VICINITY MAP Kent,WA 98032 Title: 425 251 6222 barghausen.com DATE:04/17/19 P120000s120604texhrbrtlgraphics l206(4 vmap.cdr Exhibit B Assessor Map 11/4 frt of f;� C ` '66.-z `� 5tDGJ 7:J� as4 �° s ��� .34 AC �� ,�.. w� •>�. ��� fly n2. r1�/ 7'71\111111111111111111611111i., =, v; '-'7. -�s 2n mc ra ,!,,,,,J: f� \,,,,,,,, .�� 1 5'1D 62' '.."---''''...---3'. ''----.'-ISI:\1\I 33�� /1� 1 28 AC 2,10 / Ti """'a#�' ""'-�'•,` � j 32 s Lizt�c rrL.:, ,4 t. ;5 .:,E,r ' } U8 \\ 0P . o,y', q _79 AC mS�[c ctiao p�aLc3nn , 1 � A 30 Jr` � ,,-. ,. / , , -''A, ��.�` �, • k C§2 fit.. " ,.,0 6 29 E} 01 97AC'. 11 \ 33 -----'-1' -- X r ,ir' \jikE 12 ,A r4,-.-- p 905'4,,,$\. 2001 \ { y ( \ .18 AC i11 ,.1. p/\ 34AC ` 33 ah 1C ptA ( g 25 l. i', r s..„„3,.., \.4 - ?. (9 0 9°3 --- 24 5y �a2� Vve.. 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V �` a�`; fr \‘'`.s.,"'`\� se'tcP/ �F /�/ 709 ASC �\ 3'/ N. !Yom/.\\*, \\,,,,,,,s . / ''''''<' \90 .\ /'`n ti9'r \'sa REFERENCE: Washington County Department of Assessments(April 2019) Scale: For: Job Number Horizontal: N.T.S. Vertical: N/A McDonald's Remodel (Main St) 20604 IZIBarghausen Tigard, Oregon Consulting Engineers, Inc. Title: 18215 72nd Avenue South ASSESSOR MAP Kent,WA 98032 425.251.6222 barghausen.com DATE:04/17/19 P.:i20000s120604texhibitigraphics120604 amap.cdr 1� Exhibit C FEMA Map • 044 M�F y , F v3 �y � � l S m LIJ (/) Q I I 00 o0 CT Q Ski,- co o c��<ti z eG s N� co C)-\4 SNC' tar 0 G` ,GN Pp Zoa T RD27,q3ST0 /c'�• �� ss0p�P� SITE SW GARDEN PL y �° T,<• t.N\'047,, ct- , ST ' �►SW ELECTRIC ��� �. Sw .\.'„,,r ,,,,,,',' ._,_ \ RSTST ;O '') c = ,�53 \ CO ZONE'S .J</ s� �\N LEGEND =AE.: j �� <9 �. J �\ - 1) OTHER AREAS 4/ ZONE X Areas do enn nod to ne ou[sidc the 02°% 41 ' lfFf 147 \.: annual chi,..e looaplain. REFERENCE: Federal Emergency Management Agency(Portion of Map 41067C0542E. Nov. 2016) Scale: For: Job Number Horizontal: N.T.S. Vertical N/A McDonald's Remodel (Main St) 20604 rEIBarghausen Tigard, Oregon Consulting Engineers, Inc. Title: 18215 72nd Avenue South FEMA MAP Kent,WA 98032 425.251.6222 barghausen.com DATE 04;17119 P:120000s1206041exhibrtlgraphics120604 ferna.cdr 1ái Exhibit D u Soil SurveyMap p �\ s \� a i \ 7 is f, !s`U 01 \, x • td '� '3-. .--1,.. ... ^(, ,' tgfi i -"1"';'"i:* , 7 m � ,�4:.,,,,. 1,,, +R T,C,i #?•- j;';:�' 1 " :',., i'k ,.h • C' .,,.1` V• is„x .,r d�x >:s„�`;"�,"r:. y� .F�� A�St,. .0<,4..'R" ..- '-..e`>""'y,��,',;�fi »:"' ,..,�,:: 4..�w�t ''r" •.'4 �jta' 't�` At r k.n r j* '1.,-x` '«fi„:”,,4". . ,0'� ,Wr> ': I fit garAli:` r, 4 'k., '' ?,.. +; ,. r'., '.,-- „ � `'� �-�..'�, ";I------:;74; '••. ;,1.:."4,-, , 4:. ;+3,t . a a .r .^..fi r'. `,'," ''';"','''d`. : " .. I. ,kf.';'x`•,��G��as � s tib'i. 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Frr \ Y \. N\vvva&v� , ..a'.',. . A\\vA\\\\vA\��0\0V\\\v�iavlvAOVU1,AA\,v.,. . ��_,,,,_».,.». Ao\1\�x3�S. a. ....... ....... ...»ww O • c%1 2.0 METHODOLOGY Drainage at the Existing Site From review of the existing site survey, the site is graded so that runoff flows south towards a 3.5- foot by 6.5-foot catch basin within the southern parking lot ingress/egress easement. Drainage is then routed to SW Scoffins St. where it enters existing City storm infrastructure and continues west. There is only one catch basin located onsite down a stairway next to the existing restaurant. There are no anticipated impacts on existing drainage from the site development, as the proposed redevelopment will maintain existing drainage patterns and flow rate by reducing the net impervious area on the site prior to discharge to existing City storm infrastructure. Infiltration Testing Results There are no infiltration testing results provided for this project site. However, soil maps from the Natural Resources Conservation Service(NRCS)were utilized to analyze the soil, conditions in the site vicinity. The area is known to have a groundwater level between 24 to 36 inches below grade. Description of Proposed Storm water Management Techniques The proposed project includes the redevelopment of more than 1,000 square-feet of impervious surface. Per Section 4.05.1 of the Design and Construction Standards of Clean Water Services exceeding this threshold requires a permanent water quality approach. The impervious area required to be treated for this project (pursuant to Section 4.05.5(c) of the CWS Design and Construction Manual) is all new impervious surfaces and three times the modified impervious surface, up to the total existing impervious surface of the site. Using the 7,807 square feet of modified impervious area, the required area for treatment is 23,421 square feet. However, the site's existing impervious surface is 14,051 square. Therefore, the total site impervious surface of 14,051 square feet is required to be treated. 20604-001.docx .. \:z^ry Y"R.. ., ""� , "..\. \\ ,\ „ .... ..., AAAA\\ ..�" - 77, 7,-,1,—„,4, .r sM'. >". .\, � v. , ...,.. „ \\ .,.K n \ \,\ ,. .".. ,...i,\,\\n . ��. � .,.,. \\ .::".,.. ,.,.. s..,..: \ ,x..,, " \ .... «I'..,n.,\ .... <. \'.4".,,,A1:;!4 i-. \.\\\ .. . Vin\. ..,,�. „.. � . a\ ,.. \ ., . , iik\�, "N >., ,,,.- <.,. ,ice ,. .�\\ ,. , ,\ , \\\\, a w , -.. AAAA\ � \\N 4, � \\\ \\\ l \�\\\,\ ? AAAA\\\„\,.a;,,. \\,AAA\,,,n .- \,\\\4,\ ,. , . �.., \ ,., .,N. , ..,\ \ -..�".. \ \,; ....v ,\ #.. ..:: �,, a\. �, .,...4 :. \ \ „ t... •4. AAAA \ \.\,4• r n �,.,;. \�..\ . \, \ ,. >. \\N,\. \.,, ,{ AAAA \.. \\�,...\\,,. .. � 4r, :,.,., \, a , AAAA a., >� :\� , , , ., .., "z,....... \ ,:.,, ,\ G n.... , '::. ,.\\ a ,/� "". \s. sito • C • M 12 CZFEE • 3.0 ANALYSIS Design Assumptions The project proposes a reduction in impervious area from the existing developed condition and such reducing the off-site flow to the city infrastructure. The result of the comparing the existing condition and developed condition represents a reduction in flow from the site and detention is not required for the project since there is a reduction in impervious surface and off-site flow. To meet water quality standards, the CWS Design and Construction Standards Manual first requires the consideration in the following order of hierarchy: vegetated water quality LIDA, proprietary systems meeting requirements found in Section 4.05.8, or an alternative water quality approach if any. If these techniques are determined to be infeasible due to site constraints, topography, or soils, then a regional approach may be considered. LIDAs can be determined using the site conditions described in Section 1.0 of this report and Table 1 from the LIDA handbook. Based on the known high groundwater (24 to 36 inches below grade) underlying the site vicinity, infiltration is not feasible for this site. The site conditions are also known to have steep slopes (up to 9%) , the retaining wall in the northwest landscape area, and the remaining existing trees, surfaces, and grades onsite make most LIDA techniques infeasible. The following is a discussion considering the feasibility of each LIDA selection found in Table 1 of the LIDA Handbook: • Green Roof: This LIDA cannot be used since the existing site scope does not involve redesigning the existing roof structural ability. • Porous Pavement: Porous pavement is infeasible since it requires the groundwater table to be a minimum of 10 feet below the facility's bottom and the site vicinity groundwater is a maximum of 36 inches below grade. Moreover, porous pavement is not feasible on high- use sites due to its porous characteristics. • Flow-through Planter: The flow-through planter would be feasible if the site possessed a location practical for water to be directed towards the facility, however the existing parking lot is graded away from all planter strips. The planter islands in the proper locations for a flow-through planter would be too steep to support the system. Moreover, the treatment requirement is at least 14,051 square feet of impervious surface which would size the planter strip at 843 square feet. The site will have less impervious surface in the post- construction conditions and the site topography is not conducive towards conveying the required areas towards qualified planter islands without extensively regrading the site beyond the intended scope of the project. • Infiltration Planter/Rain Garden: The infiltration Planter/Rain garden is not feasible due to high groundwater found in the area (24 to 36 inches). Rain Gardens need at least 48 inches of depth per the LIDA design handbook which encroaches on the groundwater levels. • Vegetated Filter Strip: A vegetated filter strip would be feasible in locations where planter strips exist and grades promote flow towards the planters. However, for the same reason as the flow-through planter, the existing parking does not flow towards planters and the existing topography does not support treatment of all impervious surfaces. • LIDA Swale:The LIDA Swale cannot be placed in steep slopes nor can the existing parking lot be regraded to promote drainage towards planter strips where a swale could be placed. • Street Side LIDA Planter: According to Table 1 in the LIDA Handbook, this Planter is not suited for areas with high groundwater and onsite locations that would support this LIDA are not downstream of runoff. 20604-001.docx • Proprietary Units: The LIDA techniques are infeasible as determined by the preceding analysis. Generally when this is the case, treatment can often times be provided via an approved proprietary unit. Therefore a Contech Stormfilter media cartridge manhole is proposed to treat as much runoff as practical. The location of this manhole and detail sheet is provided with this report in Exhibits F and G respectively. The project proposes to treat 12,209 square feet of impervious area including 4,069 square feet from an offsite basin area that naturally drains to a low point onsite where a catch basin is proposed. The southern parking lot is left untreated due to causing the bottom stormfilter manhole invert to be deeper than the existing infrastructure proposed for connection. The area remaining to be treated is 2,292 square feet. The most effective and practical treatment basin will not be able to treat 100% of the impervious area required to be treated even when treating an offsite basin area as shown in Exhibit F. As stated previously, the project will be decreasing the impervious surfaces on-site and thus decrease flows discharged off-site. The project proposes to treat 12,209 square feet of impervious surface and rely on the existing public drainage infrastructure for the rest as the development will overall be less taxing on the existing system. The project seeks relief from the preceding water quality methods to prevent significant disturbance and deviation from the original intended scope of the project. The CWS manual lists the option to pay a fee in lieu of the remaining required surface area for water quality treatment due to existing site constraints. Approved Storm water Sizing Calculator Narrative Form and Printouts No LIDA facilities were considered to be feasible for this project. Therefore, no forms or printouts were necessary. 20604-001.docx 13044101431C;0-11-4 l. , ....« \\ \..\..Xv .'":' ,:',:.--001151.1%;:,,,, ice \. .. \ , 1 ...f. X... „\,x, .vt. .. 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'r v.."a ,< .<„�i��. ..".<.,�\ \ \\\ ,.,,.., .�Y.. , r.,, \\\\\\a,A J\.\A. ,... he. -., ://'4446"/' ,, o- .:. ,7. ;- ...,. ..,, ::,.,. �- .,\\\\ \\ ,. ,,. .�..;�;.\\ 4\,: .yam na �,� \\��`v`"�\v\a�\�w, � < ��� ��. ,. ,v�vov\o\� �, x, . �,,.,x\ �,v_<.,�v ,�,,,, �«, , ., ., .v//t,..,„;� e�\�V\\\\\v�\\v\<. o��a�v�,xx�� < w� � h,. .. t �v,_. - 0 ■ dm 12 4.0 ENGINEERING CONCLUSIONS It is believed that the proposed facility meets the pollution reduction requirements of the City of Tigard Stormwater Standards for 12,209 square feet of the required 14,051 square feet required for treatment. The Fee in Lieu of program is requested for the remaining 2,292 square feet required for treatment due to site constraints limiting treatment ability to 100% of the required treatment area. 20604-001.docx lts , ,.. ,., y��\\ .., \\ „�P •vv„ :..., »,-, <s- :�„ »�'.. -i�< s..'. ,.. s. 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H �\ c . 1,.y, . » ',.„::',',4'..,", 4::',,;040740,1 a \a ,r ., .. c - \ . 4\ \ - �. te Y " . � � _ 4 � , ,\ \ «\ \„rt ,vim „ \ \\\\\ _ ._ ,:. . \ \ a\ , t„. lxtee,c .,,,, ,vrk,,.itijipoigp.::-:-,--rxsik4,it,gaqm,:,ip,,:4.k:;;:,<.;;t',,.„ Vii,, , .. \\\fir, \\ \\ ,,\ ,,,rt n „ ,: * .,, , .. \\\\ \\\ _<.,...4 »��, _ ���z,,,_'y ,gyp .0,.Q »�g , tea .,n , ..\�\\\\\\\\\\,Ik,n,tv,, ,-,. ,1_„s._. ti.,�\v.»„A� b��. � ��y .,«. ��A.ay.��\�\\\v��I 0 ■ L 11.1 1 RS 5.0 STORMWATER FACILITY DETAILS / EXHIBITS The following exhibits are provided herein: EXHIBIT E Existing Conditions Basin Map EXHIBIT F Water Quality Basin Area Map EXHIBIT G Stormfilter Standard Detail 20604-001.docx • • • Exhibit E Existin Condition vv Basin Map 444 4f,-4 4141,-4'f41744,1,A4104'444444 g'4.44.4-,,,WS j4 3f Y C — . . . . . . . . . . . :144"4# .... „„ *Ailitr:ir Adr ....- 40P 44 0„.1.----AV' /... , v ....\ //,./". . . . . y / . - . ,.. . . ... --- . . . ,'-' '-- 9, _ .. l•"' . . _ 9 . . , , Vrr -------- -- , ... r • ,-- ‘,,,,,\-----\ 1 A ‘ . ,111f/:/‘:IIH P. ' - •,:fel--"At Iv, I Al • „If f i ---/---;;._;,---;--'' , (-) ,-.,--- --'-.,_--:--------r-'-'- \\,._.., • - 4"*"*" - 0/ ,, , ..„--- -.- "-- , \ , ,___. (Th ,..., , . , ..--,..._,„.„ Exhibit F Water Quality Basin Map nom. ep e to, Q , ,tiic tfq d 5 Lfi \r, ,'�""^��e3o 00170r 1'4 i, j G ,r ti kM� A.. EY.- ity4 k K ? d 4sr st • ‘ \ . • , •,,,;,• - -I ° - 1 '"'. 'ttt'44141 k . . ‘ .' A \ \ ,,,,: -....- _,- ' 4,,, )„ ,ss 4,,,• ,, .* • s .,.., 1 0.-- NIS114rqb„lb. Ato ‘ " . • . - , .. N. . iqk ‘ v ........- v •.; . . , ,,,,, ,,, 1 ' 1 . --„,..,„3 ....- . • . ' , ilk ' ,1111 , ,• ,,, ‘ , • r. 1.= , . v . , =i; .• ) i 1[ 4„... ' - .'. ' . . ., - • . \- ..,___----- - • _ __ I\ ". 1r • ,,,,, .". V . ' .\ 1.- '41'-‘ ‘ '„----- \ -v, . , 6• 't, • • „,,,,,,, , ,• , , A - '• . ,, • ,, _ , , ,, ,-,1,- - -, .. ... : , . . , \ swi'----- k \ i% • \ • ‘ ' - ' , „:.. •>,., - )16, ..,,, , \_.:-.: \.‘)‹. - -------- • X •-, ..„•• -„, ,. , '‘‘,,,‘ „\. . . \ ' \\\ .., - - .. • i. .... • -- - - -_ _, ‘ ‘ . - Ii*\ , . •", . • \ . .N \ ,,,,, • .\,,,, ,, ‘, . ., - • \ ' r- , .. . , \ L \ - v , ., ‘ , \\„\\ .,„ ,*,._ . .,,, . .. \\\ , , ,..,.,-, _-- .... \\„,-, •,,,,,- , ,. . ---- ...\,' - ,... • , \,. .. ,. . • ... , \---\\ *,-_-- • \\\\\\ --,-----w.-- \ \\\ N ' - Exhibit G Stormfilter Standard Detail 14 r � r yy t FCOLI, \ A CARTRIDGE SELECTION `' \J \ CARTRIDGE HEIGHT 27"[686 mm] 18"[4: INLET o ]1�..�1L1�' i N i RECOMMENDED HYDRAULIC DROP(H) 3.05'[930 mm] 2.3'[71 ]��^\�I1=® � OUTLET SPECIFIC FLOW RATE(gpm/sf)[Us/m2] 2[1.30] 1.67*[1.08] 1 [0.65] 2[1.30] 1.67* I -/ i CARTRIDGE FLOW RATE(gpm)[Us] 22.5[1.42] 18.79[1.19] 11.25[0.71] 15[0.95] 12.53 - �1 f j 111W *1.67 gpm/sf[1.08 Us/m2]SPECIFIC FLOW RATE IS APPROVED WITH PHOSPHOSORB®(PSORB)MEDI/ 41411misofr TOP SLAB ACCESS 04'-0"[01219 mm]I.D. SEE FRAME AND MANHOLE STRUCTURE COVER DETAIL (04'-10"[01473 mm])O.D. STF PLAN VIEW wA STANDARD OUTLET RISER PEE FLOWKIT:40A n a a RE- 0-<�'� --�"-,'-',.*-�=i'= CAE 011" it.0 4_-"'d''"1.04 NUI ,ROUT TO Is ) CONTECH :oat lI CAE D GRADE t ,.w.co. .Es MEI \ � : . 1/� o?* < ;*_r`-. � PIP q • Fi:t f"o GRADE J �Or'•"a INL G/RISERS \N ' INL OU ti u / 7/<////7j</// RIN AN- 1 e • 1 FRAME AND COVER No' (DIAMETER VARIES) Il FLOATABLES N.T.S. BAFFLE ,PE GENETNOTES F U 1. CONRLETECH TO PROVIDE ALL MATERIALS UNLESS NOTED OTHERWISE. I- x 2. DIMENSIONS MARKED WITH()ARE REFERENCE DIMENSIONS. ACTUAL DIMENSIONS MAY\ w 3. FOR SITE SPECIFIC DRAWINGS WITH DETAILED VAULT DIMENSIONS AND WEIGHTS,PLEAS! III �• = E LLC REPRESENTATIVE. www.ContechES.com �l��l o o 4. STORMFILTER WATER QUALITY STRUCTURE SHALL BE IN ACCORDANCE WITH ALL DESIGN j Z ED DRAWING. I PIPE o z.,_.- - 5. STRUCTURE SHALL MEET AASHTO HS-20 LOAD RATING,ASSUMING EARTH COVER OF 0'-5 , v li 1- w m BELOW,THE OUTLET PIPE INVERT ELEVATION. ENGINEER OF RECORD TO CONFIRM ACTU Z MEET AASHTO M306 AND BE CAST WITH THE CONTECH LOGO. ____I__ i -O 6. FILTER CARTRIDGES SHALL BE MEDIA-FILLED,PASSIVE,SIPHON ACTUATED,RADIAL FLOW / 1 I }_ BE 7-INCHES[178 mm]. FILTER MEDIA CONTACT TIME SHALL BE AT LEAST 38 SECONDS. ��-,�i��• 1 J ,... = 7. SPECIFIC FLOW RATE IS EQUAL TO THE FILTER TREATMENT CAPACITY(gpm)[Us]DIVIDED I i-�� t 8. STORMFILTER STRUCTURE SHALL BE PRECAST CONCRETE CONFORMING TO ASTM C-478 ArAlikVagi INSTALLATION NOTES A. ANY SUB-BASE,BACKFILL DEPTH,AND/OR ANTI-FLOTATION PROVISIONS ARE SITE-SPECIF STORMFILTER SPECIFIED BY ENGINEER OF RECORD. CARTRIDGE B. CONTRACTOR TO PROVIDE EQUIPMENT WITH SUFFICIENT LIFTING AND REACH CAPACITY FLOW KIT OUTLET SUMP HDPE OUTLET RISER C. CONTRACTOR TO INSTALL JOINT SEALANT BETWEEN ALL STRUCTURE SECTIONS AND ASS D. CONTRACTOR TO PROVIDE,INSTALL,AND GROUT INLET PIPE(S). E. CONTRACTOR TO PROVIDE AND INSTALL CONNECTOR TO THE OUTLET RISER STUB. STOF • OUTLET STUB AND SAND COLLAR. IF OUTLET PIPE IS LARGER THAN 8 INCHES[200 mm],CC SECTION A-A STUB AT MOLDED-IN CUT LINE. COUPLING BY FERNCO OR EQUAL AND PROVIDED BY CON' • F. CONTRACTOR TO TAKE APPROPRIATE MEASURES TO PROTECT CARTRIDGES FROM CONS ageft .x ...� \ ..\ \ .N <... \., \ \ .., ,., fir,\\ ,f » _.,.. .. ,.:.. ,,, .,, ,.,. ...a.,a \\ .: .<:> ,,v �.....,,,. 1,,, . .: \\\\\\\\\\\\\\\�\•\ \, „A xx„ T .., ....r \\�\\, ,, • \• \., h\`t,>„.\ x x,, „ ,1:4 Vii..„s, .,, :. .. \, <. • �',\\\a�. \\\ �k \ „� 4. moi. „\ C,. \,\�\,.2 .. . ,M ..., --v. ,. .r \. a ..\\\ .,."..dam � .,,... ��» = .,r :::, .. .�, i'„ • \, \�,,.,,,.. ® ,v� o\ ., , _ y; 1, rait .....gtbigqtpmg ,.. ..� ,. �. .., z fig, \\,\ r. � \ ate.,�. \ \ .. , a \ \ ,,. .,. r , � 9. ie ., - ... .,. ,.... < > .. >, ..».. >,.,, a\..\\\ ...,. ,, , „ , ...,�.: r.. ., .... fi„ r ........ .. .."� -.....r. ,gin .... >. .,_� � ... � ...\, a.. ..� \. \ >.,... \,\O\\ -. _ ..<.. a ..,. .... �,. .,. ,,.. ...,.. ...».,.\\ \\\ \\ \ ,....� ..a .. ,..... .:..N a :-. >.;». t-, ,, ,,,. �, �� fps. � \ v ,x t, ,,.,, , '46.12.41'4''''' <.». » „z \ \ \� � ,.. a w :., .:.. . � .�, \\\,\ \ \\�Ir4 a,. .tea\\ \\,� >a' 0 ,, . ,,. \\ \ \ \1 h fi \\ \ ,,\ \ � \ yv\�\E . � . . �\�\v \2,. \ \ z > -.� �a ». _ _�� \yw „ , �� v , �P a � , , \ w�yv � ���.�,,,'., � . ��a� , »»M.,� ��> .... > ,, 0 ■ CO 6.0 OPERATIONS AND MAINTENANCE (O&M) PLAN AND O&M FORM The Operations and Maintenance (O&M) Plan and O&M form will be provided in a subsequent submittal. 20604-001.docx \.,,,. lid` \.. � �•\ \, ,.. �\ , �<. ,�. ..� c ,r, -y 9.,.,,,. \ \ ,,,. t �- N\\ a x. tea .:., ., ,. ,, s ,t; .,. , , -. ... -<, � a �\, ,rte �,n; e.,. 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The project does not request any Special Circumstances. 20604-001.docx , \, i,. 1, a MY ,, \\ , ... „ \`, \\ ,,:... ::, A<:P \ \, \ \ .,a r Ra . \ \ �_.. -> \ V''''';'''''''''"'''''''°:''' .>. ... ate v,,,. �,>.<�: ,.\. « ,,,. .�. .. .,.. ,, .v \„\ .,� ,-.. a-r , .,. �r< �, n \ . . ,. , v\, \\\, ,,,” �, ;. „ ,tea ��;t?ae� \\ � , ,\ , P \� \ � . 1 . � w, �'..� ., \, \ � \ yr �.,: � r if .. >> - 1 e \ \ �` lam. �\\ � \ < � \ \ �, � \ \ r A � \\ ,... �\,\, ,... , .\. � ' .. \,....\\`a�.: r: :,. \\ ,+• 1. ,.,.. ... ., ..\\ ,. r .. ,. .\ ... ... kw, "044,41„:-..%1:44/4-404.4.<<,..<<<'''''''''"'-'-'14%y k \., ,- ........ \ ., \ ..,\\ : \.\ ,... , .., . .\ \ .< . yr . . „ .. , .\„ . . .« \ ....„,„....,4, ,. , ark r, \.. , , . 0 ■ 00 12 CICS i--- i 8.0 ASSOCIATED REPORTS SUBMITTED There are no additional forms to include. 20604-001.docx