Loading...
HomeMy WebLinkAboutDrainage Reports - 05/18/2016City of Ft. Collins pro d Plans Appme By Date INTERWEST CONSULTING GROUP March 2, 2016 Mr. Wes Lamarque City of Fort Collins Stormwater Utility 700 Wood Street ' Fort Collins, CO 80522 Re: Lot 1, 3 and Tract A, Warren Federal Credit Union — East Drake — Final Drainage Report ' Dear Wes, ' Please accept the following letter report on behalf of Warren Federal Credit Union to demonstrate the site's compliance with the previously approved Final Drainage Report for Rigden Farm Filing Six and Rigden Farm Northwest Roads as prepared by JR Engineering. INTRODUCTION ' The site, Lot 1, 3 and Tract A — Warren Federal Credit Union — East Drake, is located in the northwest quarter of Section 29, Township 7 North, Range 68 West of the 6`h Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. See the attached vicinity map. The project is bounded on the north by East Drake Road, on the east by Iowa Drive, on the south by Limon Drive and the west by Lots 1 and 2. ' The project contains about 1.5 acres of land. The proposed development consists of the construction of a ' bank commercial/retail building, on -site parking, on -site sidewalks and landscape areas. The public walks on the south, east and west will be completed with this project. ' Lots 1 and 2 will not be developed at this time but will be considered in their ultimate condition for this drainage study. All lots and Tract A drain to the North Tributary Storm Sewer in Drake Road. All detention and water quality volume requirements for these lots and tract have been met by the overall Rigden Farm development. EXISTING CONDITIONS ' The proposed site lies within the Foothills Master Drainage Basin and is part of the overall Rigden Farm drainage plan. Detention is required for the site and is provided by an existing off -site water quality and ' detention pond. The site is currently vacant and contains dirt, and dryland vegetation. There are no mapped floodplains on the property. ' Lots 1, 2 and 3 and Tract A correlate with basins 103a and 103b of the Northwest Roads Ultimate Drainage Plan. Please refer to the attachments for Sheet 10 and 11 of the Northwest Roads Ultimate Drainage Plan. Page 1 ' 1218 WEST ASH. SUITE C WINDSOR. COLORADO 80550 T[T. 970.674.3300 • FAX. 970.674.3303 PROPOSED DEVELOPMENT ' The drainage for this site has been designed to be less than the maximum allowable runoff from each basin as stated in the Overall Rigden Farm drainage plan. Table 1 compares the actual runoff versus the allowable ' runoff from the Northwest Roads Ultimate Drainage Plan. Runoff from the four basins (A, B1, 132 and C) are to follow the intent of that plan and are to be collected in storm inlets and piped to the North Tributary Storm Sewer in Drake Road. Please refer to the attachments for the hydrologic calculations of the 10 and ' 100 year storm events that were performed utilizing the Rational Method. Table 1. Comparison of Flows. Ri den Farms Northwest Roads Warren Federal Credit Union Subdivision Basin ID Contributing Area (Acres) 100-yr Design Runoff (cfs) Basin ID I Contributing Area (Acres) 100-yr Design Runoff (cfs) 103b 0.93 9.3 A 0.51 5.1 103a 1.15 11.4 B1 0.44 3.8 B2 0.65 6.0 C 0.40 3.9 Totals 2.08 20.7 2.01 18.8 103b 0.93 9.3 A 0.51 5.1 103a 1.15 11.4 B1, B2, C 1.49 13.7 BASIN DESCRIPTIONS The site is divided into four basins: A, B 1, B2 and C. ' Basin A is 0.51 acres and is comprised of drainage from the roof of Lot 3 and on -site sidewalks and landscape areas. Water will flow from the roof drains into the proposed drainage system that ties into an existing stub from the existing storm system in Limon Drive. Water from the proposed sidewalk along ' Limon Drive will sheet flow into the curb and gutter of Limon Drive where it will then be collected by the existing inlet in Limon Drive. Basin BI is 0.44 acres and is comprised of the eastern portion of the Tract A parking lot, on -site sidewalks and landscape areas. Water will flow into the proposed parking lot, across pervious pavers and into the proposed Type C sump inlet at design point B 1. From the inlet, water will be transported via storm drain pipe to the existing storm drain system in Iowa Drive. Water from the proposed sidewalk along Iowa Drive will sheet flow into the curb and gutter of Iowa Drive where it will then be collected by the existing inlet in Iowa Drive. Basin B2 is 0.65 acres and is comprised of the western portion of the Tract A parking lot, on -site sidewalks and landscape areas. Water will flow into the proposed parking lot, across pervious pavers and into the proposed Type C sump inlet at design point B2. From the inlet, water will be transported via storm drain Page 2 ' pipe to the existing storm drain system in Iowa Drive. Water from the proposed sidewalk along Iowa Drive will sheet flow into the curb and gutter of Iowa Drive where it will then be collected by the existing inlet in ' Iowa Drive. Basin C is 0.40 acres and is the comprised drainage from Lots 1 and 2. It was assumed to have a percent ' imperviousness of 73 percent with assumed areas for roof and sidewalk. Water from Lots 1 and 2 will flow be routed into the proposed manhole at design point C. From this point water will be transported via storm drain pipe to the existing storm drain system in Iowa Drive. Please refer to the attachments for Warren Federal Credit Union Drainage Plan that depicts the drainage basins. The original design used a percent imperviousness of 90 percent. The weighted percent imperviousness of the proposed plan is calculated to be 73 percent. Therefore, the site is in substantial conformance with the ' previously approved Final Drainage Reports. Hydraulic calculations for sizing the proposed stormwater inlets and pipe discussed in Basins A, B1, B2 and ' C have been completed using area inlet spreadsheets and StormCAD hydraulic modeling software. Calculations are attached and show that the storm systems in Iowa and Limon Drives have capacity. ' FOUR STEP LOW IMPACT DEVELOPMENT PROCESS With the development of the site, the design team has followed the four step low impact development process outlined in Urban Drainage. Water quality is required for the site and is provided by an existing off -site water quality and detention pond. In addition to water quality, Low Impact Development (LID) criteria must be met. It is required that no less than fifty percent of any newly added impervious area must be treated using one or a combination of LID techniques. For Lots 1, 2, 3 and Tract A, 51% of newly added impervious area is treated by pervious pavers LID technique." It is also required that no less than twenty five percent of any newly added pavement areas must be treated using a permeable pavement technology. For Lots 1, 2, 3 and Tract A, 25% of newly added pavement is pervious pavers. Please refer to the attachments for LID calculations. Please note, calculation includes assumed roof and sidewalk area for Lots 1 and 2. Page 3 Table 2. LID Compliance. eryious"Afda 60 266. acre/sq. ft. Minimum Iinbervi6us.Area to be Treated. 30,133 acre/sq.lk lrea of Paver Section til'(Basin Bl) 4828 .,acre/sq.-ft. 'avement area for Paver Section k (up to 3 1"is perm ted) -10,977 acre/sq. ft. mpervious Area Treated by Llb.TreatmentfMethod Wi (Pervious, Pavemenisysiem). 1'1,930 .acre/s-grft: lrea of Paver Section tit (Basin 92i '5,427 acre/sq. ft. 'avement area for Paver Section ti2 (up to_3:1 is,permited). 13,977 .acre/sq.'ft: mpervious Area Treated by LID.Treatment:Meithod n '(Bervious Pavement Sy tern). 18,567 acre/sq. ft'. otal Impervious Area Treated 30,477, •acre/sq..ft: \ctual % On -Site 'Treated'by LID 151)% 25%'Porous Pavement Requirement; dew PavementArea __ _ 33,209.acrejs4..ft. . tequired Minimum'Area.of Porous Pavement a8,302 .acre/sq. ft: lrea of Paver Section #1 J,828 -acre/sq. ft.- lrea of Paver Section #2 _ ,, 5,427: -acre/sq. it. .... _� .. . ___:. __... . ......... "oral Porous PaJemerit Area ,8;355 .acre/sq.:ft:. lctual %of'Porous Pavement Provided 15'% An erosion control plan will be implemented during construction that will address source control and unwanted materials (hazardous materials, sediment) from entering the downstream storm systems. The contractor will be responsible for implementing the erosion control plan and adequately addressing any spills or clean up on site. ' The proposed redevelopment has improved upon the existing conditions by providing off site water quality and detention and onsite LID treatment. The site has been designed with provisions for safe and efficient ' control of stormwater runoff in a manner that will not adversely affect the downstream storm system and will improve water quality. Overall, it is evident that the proposed redevelopment will have a positive impact on the overall stormwater management system. I Page 4 STANDARD OPERATING PROCEDURES Pervious Pavers Maintenance Plan Routine Maintenance Table (Summary from Chapter 6 of UDFCD) xequirea Action Debris Removal, Sweeping, and Vacuuming Snow Removal Full or Partial Replacement of Pavement or Infill Material 1 iviaintenance unjecuve Remove debris with regular sweeping of the pavement surface, typically performed with a broom sweeper. Removing solids from void spaces will require a vacuum or regenerative air Sweeper. Conventional plowing operations should be used for snow removal. Do not use sand or deicing liquids on permeable pavement systems. If sand is accidentally used, use a vacuum sweeper to remove it Concrete pavers, when installed correctly, should have a long service life. Follow industry guidelines for installation and replacement after underground repairs. If the surface is completely clogged, restoration of infiltration can be achieved by removing the first'/x to 1 inch of soiled aggregate infill material with a vacuum sweeper. Replace with clean aggregate infill material using a push broom. Inspections Inspect to ensure that the facility continues to function as initially intended. rrequency of Action Routine — Sweeping should be performed weekly to monthly depending on the season. Frequency of vacuuming is site specific but recommended twice annually to maintain infiltration rates. Non -routine — Performed as needed after winter storm events. Non -routine — Performed as needed when surface infiltration becomes completely clogged or when individual pavers require a repair. Routine — Inspect pavement condition at least annually, either during a rain event or with a garden hose to ensure that water infiltrates into the surface. Systematic measurement of surface infiltration can be accomplished using ASTM C1701 Standard Test Method for Infiltration Rate of In Place Pervious Concrete Page 5 Storm Drain Lines Maintenance Plan Routine Maintenance Table Rennirerl Artinn Maintenance nhiertive Frennencv of Action Debris Removal from Inlets and Catch Basins Remove debris and trash from inlets to prevent them from continuing downstream or clogging and reducing the flow capacity of the system. Non -routine — Remove debris as needed after storm events or seasonally such as during the Fall with heavy amounts of leaves and twigs entering the system. Debris Removal from Storm Ensure the pipe systems Non -routine — Pipe cleaning is Pipes function as intended. Reduced recommended as needed based capacities in the pipes will on the results of inspections or cause the system to back up when the system is no longer and increase the frequency of able to regularly convey surface flooding that could routine storm flows from the damage property. site. Inspection Use a video camera to inspect Routine — Visually Inspect the condition of the storm pipes and inlets at least drain pipes looking for annually or after major storm sediment buildup and events. Every 2-5 years the structural integrity. Clean out pipes should be inspected with pipes as needed. If the a video camera. integrity of the pipe is compromised, then repair the damaged section(s). If you have any questions or comments please contact me at (970) 460-8471. Sincerely, Michael Oberlander, P.E., LEED AP Colorado Professional Engineer 34288 Attachments Page 6 0 E. DRAKE RD. Q Q 0 SITE w Of Z J (n ck� O w Z m � J H J CUSTER DRIVE VICINITY MAP SCALE: 1 " = 500' II II I 1 II 1 I 1 11 11 t 1 EASTDRAKEROAD ------------------- - jH IaMpM.]D � p]E II �7-■ ■ � — trw I IC{ y LOT TRACT U,D&A ` LOT 1 I I I I I I I 1 I 1 I 1 ' I 1 1 1 I I 1 , 1 � I 1 , � 1 I 0 1 I 1 � Z � I i I v I 1 I 1 r7 y 9 �1 -------- 1-------------- - 1 L AfONDRIVE ---------------------------------------------------- LOT f, TNFrLATSATR/GDENFARM DRAINAGE SUMMARY TABLE 6•Ian IYaN TM,My wawn Ar• Irl cltEl cl,wl rl,al IrNI rPEeI Irrl qwN. I•••I gl�lw INI rr,s wr•rIr dsI on ,m so so iI sI Em' 81rme wnm Umon DIIR a, eI a« am om sa sp Ia sa Chum MMt m m aN or• ab nIo on -7m so so- so no 2a �n eo eo rypaC 6umpRM EvNw 9blm3 •Nmm OmoR [MIS I ❑0 LEGEND ",U TING MINOR CONTOUR F: I"NG.NOR CONTOUR PROM MO MINORCONTCUR PROP WMAJORCOMWR PROPOSEOOIRECTONOF OVERLAND MOW DRAINAGE BASIN DIVIDE UNE E.I. NUMBER DRAINAGEDASINAREA DESIGN POINT W Z W p Q � W Eli I Z 1-0 20 10 0 20 60 O SCALE: 1"n 20' p Z m U E"L teaN/ CALL UTILITY NOTIFICATION CENTER OF COLORADO r NR O W 811 p $,Aly 2-0u9NES5 DAn IN ADVANCE BEGQE M MG GREVE OR E%CAVAM FOR RM YMNMD DF UNDEMPOUND •EMIIEn UnUREs. 1.' w I• pY a W Q Z a m 0 m o i 0 o _ D CITY OF FORT COWNS, COlORA00 o IUn �i 5 U UTILITY PLAN APPROVAL _ .ppoo REDIS APPROYEO: tF'.p'{BL"ryIN ey OTT wOREEn DAM �' c CHECKED BY: RAM➢ l RAS2RARR UnUTY DAIS CHECKED BY: smDlMAmI ulwry an:•DIML f CHECKED BY: PARS a TKR DALE PROD. NO. ' 21 iONO0 CHECKED BY; DALE CHECKED BY: 8 DA2 1 i cQ L D N > > E � 0 p C V1 q O O E c m J E E O N d C A N N N N G C C U% E a a E `o E E o C U U C M 8. a. 8 .N X X W H H W 0 o in m o am O 0 V N N Q O C O O O O E ui ui ui ui u S o 0 0 0 � E ui ui ui vi O O O O OD O N O O O U O O ao n n ro U o 0 0 0 u a m v Z, c m a F� N c 01 c m _ c i a Interwest Consulting Group RUNOFF COEFFICIENTS & %IMPERVIOUS LOCATION: Warren Federal Credit Unian PROJECT NO: 1219-048-00 COMPI-TATIONSBY: es DATE: 111312015 Recommended Runoff Coefficients from Table RO-11 of City of Fort Collins Stormwater Code, Volume I Recommended % Impervious from Table RO-3 Urban Storm Drainage Criteria Manual, Volume I coefficient Impervious C 0.95 100 0.95 96 0.95 90 0.50 40 0.15 0 0.20 0 Type B Soils Runoff % Streets, parking lots (asphalt) Sidewalks (concrete) Roofs Gravel or Pavers Landscape Areas (Flat, Sandy) Landscape Areas (Steep, Sandy) SUBBASIN DESIGNATION TOTAL AREA (x.l TOTAL AREA (sa.n) ROOF AREA (Will PAVED AREA (sq.1t) PAVERS AREA (sa.rt) SIDEWALK AREA (w.it) LANDSCAPE AREA (sa.ft) RUNOFF COEFF. (C) % Impervious REMARKS A 0.51 22,350 12,959 0 0 5,925 3,466 0.83 78 Bt 0." 19.093 0 10,977 2,828 933 4,355 0.70 66 B2 (165 28,470 0 13,977 5,427 4,590 4,475 0.74 72 C 0.40 17,318 13,000 0 0 1,000 3,318 0.80 73 Assmum tion for Future TOTAL 2.00 87,230 25,959 24,954 8,255 12,"7 15,615 0.76 73 Eauations - Calculated C coefficients & % Impervious are area weighted C=£(Ci Ai)/At Ci = runoff coefficient for specific area, Ai At = areas of surface with runoff coefficient of Ci n = number of different surfaces to consider At = total area over which C is applicable; the sum of all Ai's 3-2-16 FC FLOW.xls r z E z o � N 2 p w a 9,%0< a a.UA N Y W T O O O O J O N O N Z E LL "" N N N O O O O O 4 _ m ti _ «U N �� R F u m n o N o O 4 0 0 O L c o J E LL J W O O O l0 N N N N x U 0 m 0 m cc O c Lrn o 0 0 0 F o 0 o O n 0o N f7 N J 7 �rn O O O O m N N N N 0 o N N ` v h O O t N Sr O �- U m oho nn m O Z � C0 O OO N O N d A N 0 0 00 0 Z <ao mU m m (n Z yZ Q HZI O m f w Q L � a N G N N Z U U LL N � t w U O C N E N C1 c D R 'D c_ E C to co II f, C .o E E m E C E U GO z z O zzz¢ Eo V D ` Cs1 0. uo o O 0. 0 Q O m Y IE W m O O O O Q IA N N N z E IL -' OR N b O O O O O t y E m ti C' LU Y N a a o 0 W = J m U it F `•- u 7 V # o 0 O c o E � LL J W O O O N fV (V (V (V S Li OI Ip ID �D ID o 0 0 0 c0 o FR F O O O O H N w o J r Wcc f m OR n 0 0 0 0 m fV fV fV fV N N O O o L N c � < O fO N O � o OR m o m W O ^ U m n 0 o 0 06 N a N O D o O N N � N 0 0 0 0 z a m m U m m U) N Z Z m N HZI-10 F Q na aIL 0 O m 7 U Y LL N � V O C N ca E � o N N c � ea � � C E C In m II � U + O E E E .a E 11 l0 w N X 0 LL LL W N M LL LL Z c V Q } W N a Vi c FO W d p J U. Q C 0 Q V o c 7 U N 9 ^ � N F Q � O Y II U O p] N h OZ � N zz¢ � � a O oU a UU In N Y a 0 Q f O N m a m 0 F � N d 'u w 'o C o 0 U N N N O O! N N m m N N m m N N N N E N N N N U m n n m U c o c c 0 0 0 0 LL O � m a 6 U � N w G a c < m U m o n m o 3 U. z E ° Z N R Q } d w a N O F o V w M r " Q O a Q V o 9 U L u 9 u � - 3� u l U m O N Z O O o Z Z 4 oU O 7 ce i UU O N Y G Q f r O 0 r o 0 w o' c > S E a c o 0 Cl N a - mmmm C O O O O - E �ri vi vi ui U m n n m U o 0 0 0 c c o 0 LL 5 2 b < m m U wy riE 0 m m Q m m V 0 2 m N 3 LL O E Z r } Q O W O a� In M Q C = O W U J C Q LL z O O ~ Q U O � 9 V u O w o h t d u V E r o C1 y z ❑ O o zz¢ r oWCL CL oao¢ J a U O N Y 2 Q W R O Q O U N N m M O 0 f O y Q U O Y L E a c ca o a U s Ti N ei �G t7 0 ai of ai of U C E 6 N 6 N 6 6 N U o m m o Q q m O f0 O O O O O LL z Q m ¢ _ U Q m m m f 0 U W 2 G Q m m U O a U II Interwest Consulting Group 1218 W. Ash, Suite C Windsor, CO 80550 Inlet Flow Calculation for Area Inlets Project: Warren Federal CreditUnion Job Number: 1219-048-00 Calculations by: es Date: 11/5/2015 Objective: to determine capacity of Type C area inlet with close mesh grate WSEL. Geometry at inlet Grate Dimensions and information: Close Mesh Grate Width (W): 2.625 feet Length (L): 3.3542 feet Open Area (A): 6.6944 sq ft Reduction Factor (F): 50% Grate Flow: Use the orifice equation Qi = C*A`SQRT(2*g`H) to find the ideal inlet capacity.* 'See Hydraulic Design Handbook by McGraw-Hill for verificaiton of equation use and C value C = Orifice discharge coefficient= 0.67 A = Orifice area (ft) - open area of grate g = gravitational constant = ' 32.2 ft/s' H = head on grate centroid, ponding depth (feet) Then multiply by the reduction factor for the allowable capacity. Qc=a*(1-F) DP C DETERMINE CAPACITY OF TYPE C INLET AT DP 131 H = 0.74 ft Single Type C Inlet A = VA 6.69 ft2 Qi = C'A'SQRT(2'g'H) 30.96 cfs QG = Qi' F ll 15.48 cfs OV, t USE: Single Type C Inlet 7 '3•)BcJ(5 t✓ OP 6 Pagel ' Interuvest.Consulting Group 1218 W. Ash, Suite C ' Windsor, CO 80550 Inlet Flow Calculation for Area Inlets Project: Warren Federal Credit Union ' Job Number 1219-048-00 Calculations by: es Date: 11/5/2015 Objective: to determine capacity of Type C area inlet with close mesh grate WSEL Geometry at inlet :. ' Grate Dimensions and information: Close Mesh Grate Width (W): 2.625 feet Length (L): 3.3542 feet Open Area (A): 6.6944 sq It Reduction Factor (F): 50% ' Grate Flow: Use the orifice equation Qi = C•A*SQRT(2'g'H) to find the ideal inlet capacity.' 'See Hydraulic Design Handbook by McGraw-Hill for verificalton of equation use,and C"value C = Orifice discharge coefficient= 0.67 ' A = Orifice area (ft) - open area of grate g =. gravitational constant = 32:2 ft/s2 H =.head on grate centroid, ponding depth (feet) ' Then multiply by the reduction factor for the allowable capacity. QG=Q,*(1-F) DP B ' DETERMINE CAPACITY. OF TYPE C INLET AT DP B2 H = 0.67 It ' Single Type C Inlet A = 1'A 6.69 ftz ' Qi = C*A'SQRT(2"g'H) 29.46. cfs ' = 14.73 cfs C./ K t � �v . v e � USE: Single Type C Inlet Page2 JA �- z v J co O 1.4 -z �o s w J W N U Q N m 3 w w m co E Q ON N N F� co M N v- M M M fW N M M 0� N en M M O 0 c O 0 c Ln O 0 o b N co N b N H N Ln b N ti N M 7 b IA 00 M O .ti rn m 0 v N 0 co 0 m Y v u V C Y Y ai a u u V V C C Li CDO ON rl Ui IA 0 N r1 tL m U Q X W Z rZ+ co N m a a a ai rnom 7 C W � C O � W � N c~i g a, J S W N i ■ W a m m O pq O %D � Q M TJ 01 01 C W ^, 0 O O M O H .y 3 0 d �O 'O V 0 v �+ W 0 •w•1 y�y y N O M W Iyp 3 of A ■r w� i Cl W C �y t' n N > > C W E C O G! cc O > 0 l/f W W Gl Q Z O Z UM- y 7 w 'o U o cV 0 J F N D N N 0 tam Bow bNl N m O N �> via d n y o yU c d E OO o UJ N r- �co 00 0 pj 6 N M E> xrn N� N 00 3 of N M > • m � U) E O(P It00 rj N O M H m c t r 0 d � O b. O V d c Q 0 C Zr- o 7 � 009 W N rr = r) W J z° E> Wiic P') U O c O 0 oU a1 C_ yN v0 F O O � U rU la O O O O O O O O O CM CO O O O O + N O U O c O 0 oU c 0 �o ++ IA CO O r N NU MU N O c + OU 0 c VO �W O Lf)+ O m N U aU O O + O 0 + r O O 0 O O O 0 O + 0 O O O N c 0 N ofv N 0� O 3 N ON �� V` 1 V o � 1p N M N m O T fn fn en E C Gl J C W i C 0) pmp V M O M M M M M V V 0 _ � v C ti ID u M M N M M M t y coCL O O O O O Y C W In v iVp l.J O �- Z M D ai r d W p C _ M M M W ti 40�1 M _ c) i ^ N a >2 M c v ♦♦ 2 N v v G � •• d � ti O O O F C� IA IA IA x16 LL d O O O 1 N OD N N Y iW vy py py _ C 'm C ry Y Y C i g cgv as m 00 N IM en 00 R C J 5 G W O N ti +� Z Q a� O V/Z N x LLJ W.Z. al a a N N O) c ^`p do Ur 0U 0 0 M r m N 0 t3� a a us saw _m O N C > + C of O v � N p N O d U c c 0 m N N N V N v ^ rn M M u 0 CTiN� ' C J 'W N a O 1`0 C M C Ol J C W N a M 0 7 M _U 0 e 7 y.. A C � J T 2 V N M c M v J T N x m ro t o :_ vi v vay •w•, LL W o M M Ell 2 W 16 E O O M O � y f0 W O O p O C tD M y > O v W v ar Q 0 M 0 did U m a WS w U) 'D ate+N o u m a E v a 0 0 OR 0 dM� co did t~)ma LU w U) a O� 0 m 0 M O N ,Ec� ai ao� � Ln w J W A J O N � N F W coca L w.� J w D � N c N U� cV 0 61 CO C v LD m "yNr C > + �o d= �a `) o yU c c 0 a fn N 4t CM (0 7 In r 6M 3 r M N Q �E c � U) t, f� O MM O C N41 0 cc CCN_ > cc L LL C d o O �O d 107 C Z O N N c ,m 1�' NE W LL C W O O O O O In It M rf r O� O r (p M M� N QJ� c / �U O7 o c 00 C� N Oy 06 U d= o a O a (4) UOIIBAB13 O O O M O O t N O LO t r O LO t O O O O ' O L6 N F, r i --- -- R �, -- --44-- - 1 ..mot: �+91Far_]ilr .-t•-._ �` _ - 'S>:•xaS _-��� r _-' • _ _ _ _ _ .i .63 _ 14 64 6�y________-- - -es r0'MrRNeTN - - mjrY-_-_____ __--_ � t I ♦ ti + �' � � 00 i Er 1 691 1 16. to TYPE R Oft , ' Ia TYPE 9 MALT fax 1 - i IgI 1--c_____________�: Y out 106 Lj ui SRImE TYPE 99fi - `f.161M[D RrrRN / (A.. - _ - / - - I ------- 41-I \ -.-�------- - -� --p9 1 - - - - - - - - ♦ , / .' Ali 52 I--------- ---r EIICIF 4,i Iq -m�—__—c — �- - — --- - ___- 12 - '-----•• _ - _ _ _ - mGOILW is" iL - — 1,I\ ;r n CHOW �G14"C�zz<o TSCi��]S�i I, w KEYMAP s " m� CAIL UTILITY NOTIFICATION ycq¢ O"4$ 7 0 ^p CENTER OF COLORADO 1-800-922-1987 g g� x-BU9K55 DArs g kt c' N ADVANCE BEFORE m04r, ADVANCE < IE• n o GRACE, OEXCAVATE FOR TI .E Z bR MARMG OF UN0cscRauem WMBER UUTES 6 ;In ww x H vxl�. o ra F3 LEGEND t T IM M P OSM NIFT AND PPE t Ft MED ENO YCTON m MWOSEO NEET IOCATKH S — — — EnsTNc s• cwTaua 8 EVSMG V CMTOUR d mmosm s' coNTDOR PROPOSED I' CONTOUR W R SIMI m m WAPACE BASH SWIDMY W ijJC BAsIF1 N HER 10 M NNOR RUNDFT COEFFICIENT AREA N ACHES A- OESM PONT SO 23 0 . 50 100 SCNE: V - SO' ' N W W rm)sl® UPI. n[ YRGT IVT1YR90. 6 tl 300 R[CYJ/ � R" qE� m 28262 rX m l3 s PE IYp R Z rn 0- 4 Ld IIdALL WRR RAm BAN O 0 10 AM OY BD.I1T O.i1 lNmmmm { w City of Fort Collins. Colorado < f— AC z UTILM PLAN APPROVAL t�!{ a. z o APPRO N Erv..- Ox. W yE CNEEIEED 6Y: WECKED Br cwc� BY E1EMED SY: — - TAT- E.R� 10. SEER 10 OF 21 lJoll pfgtED RY: __ or. 1R3 3Wti4.15 C-3 2058 II ' I' I' 11 11 11 TRACT p— I� • , LEGEND WIN PREpOSM STOW SEWER MEET •�I'' EMSTING STORM SEWER HLET Im TOP Of BOX s^ CALL U71UTY NOTIFICATION CENTER OF • 1' 11 1-800-922-1987 CELL Z-BUSNESS DAYS W ADVANCE BEFORE YOU M, MADE. OR EXCAVATE FOR D4E UMBER UMMS 1 ha Kp ma 9 S I a 1► JWPW , • , ' , , • , CHEMD BY, .o . .•: NOTES NOTED. — - k ALL STORM SE7WER 94ALL BE ltgqrM BY THE CM OF FORT COLLINS. • 1. V �11�1��1 =NOME IN rm m MIN NMI ME Sam E;Fm=-W=m My1.•' Mrgt �� 'ems !?L� NS SEA L�c11+.1_�=� j� �u ON `ice MWIT i , Al Rem im mom WE 1 1, 11 11 LI .L 11 1 11 11 1 11 11 . L/ ..n,.•w, .. a+.wl..•u�.n l.rt•,w . ww./ r•., r .er•. _ t .Yb my.Mu�.�A[ft •..V/ Iiti�.Mt.• MCi.toYll�L..J a ' C r I 1 1 1 1 I 7 LEGEND PROPOSED STORM SEWER EXMTING STORM SEWER C-3 nsa ' «•w«,..r..w,�a^• .,,.e..rr.,.rr—rw.w.• .wwr.. y e,...r. +.r.rr�....w... ^•.mx.^ .r.^rw^.m���o. ^ EASTDRAKEROAD m%orvBlb Texm.m uD New lmperviout Arta W.S(b xrt/t9. lt. Re ulrtE Mnlmum lmpervrow Rmabbe irtatetl 34ll3 rrt Rauo Am.9l Pswr9eRtlpn Y110YIn BlI Zm xm/w. It 39 Pmmem arealwPmrLMmRSIup10 3:S is pemJRE) m9n a[rt/w. It Mpemous Nta TmtleE W UDT.—1 M•t n(Pervlvus Paremem syteml 1191D xrt/w. lt. 42 Arta N Pmr Lnwn R'B IMBSI SA21 xrt/w" P.—., ma lw Pmr bnlml (up le 3:1ISR.Il ) 13.9n xrt/s911 3,6 ImpemmtArtaiwwee UDTmumem R3emm n(wmw. Pmmem smum) IRS mw/w. N. AA — 1m "out Arta T—.J 30.AT ym/w 11 AmW B¢utl %Om9tte IA; by UV Sl% E%Mdu P�emeu[ MpYlevent NewPmm[nt Ama 3iMA xte/w M Mnrmum Artaal PmmaPmment Yrt/w It .m.m BrtaW PmrLnwn.f m zxrt/w 11 ItAm.•IPm] 9m xm/t Tm P•mwPmP—ntmem Art. flrx xmh9 n Anm%.I P.mw Pmmem P.owBN Ss % LEGEND PAVEMENT AREA TREATED BY LID OTHER IMPERVIOUS AREA TREATED BY LID so o zoo AREA OF PERVIOUS SCAM: 1 = 100 PAVER SECTION WARREN FEDERAL CREDIT UNION LID EXHIBIT I In TahlP 50%On-Site Treatment by LID Requirement New Impervious Area Required Minimum Impervious Area to be Treated Area of Paver Section #1 (Basin Bl) Pavement area for Paver Section #1 (up to 3:1 is permited) Impervious Area Treated by LID Treatment Method #1 (Pervious Pavement System) Area of Paver Section #2 (Basin 132) Pavement area for Paver Section #2 (up to 3:1 is permited) Impervious Area Treated by LID Treatment Method #1 (Pervious Pavement System) 60,266 30,133 2,828 10,977 11,910 5,427 13,977 18,567 acre/sq. ft. acre/sq. ft. acre/sq. ft. acre/sq. ft. acre/sq. ft. acre/sq. ft. acre/sq. ft. acre/sq. ft. Ratio 3.9 4.2 2.6 3.4 Total Impervious Area Treated 30,477 acre/sq. ft. Actual % On -Site Treated by LID 51 % 25% Porous Pavement Requirement New Pavement Area Required Minimum Area of Porous Pavement Area of Paver Section #1 Area of Paver Section #2 33,209 8,302 2,828 5,427 acre/sq. ft. acre/sq. ft. acre/sq. ft. acre/sq. ft. Total Porous Pavement Area 1 Actual %of Porous Pavement Provided 8,255 acre/sq. ft. 25 % Project Name: ' Project NO.- Client• Subject: Date•2 q / .By: 5 With: I1 1 — �.l 1218 W. ASH, STE C • WINDSOR, COLORADO 80350 1EL.970.674.3300 • EAX.970.674.3303