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Home My WebLink AboutDrainage Reports - 07/21/2014J City of Ft. Collins reeved lans Approved By Date — Final Drainage Report The Learning Experience at Miramont Office Park January 31, 2014 Project No. 12026 Prepared for: Adam Rubenstein Rubenstein Real Estate Company C/O The Legend Retail Group 5150 E. Yale Circle, Suite 400 Denver, CO 80222 720-529-2881 arubenstein(a)-legendretailgroup.com Prepared by: Where Greot Places Begin 8000 South Lincoln Sheet 8208.1 Mew, CO 801222 Office: 1720) 283.6783 1 www.redlaod.com Contact: Mark Cevaal, PE mcevaal@rediand.com DLLAAN� L � Final Drainage Report for The Learninq Experience at Miramont Office Park ENGINEER CERTIFICATION OF DRAINAGE REPORT "I hereby certify that this report (plan) for the drainage design of The Learning Experience at Miramont Office Park was prepared by me or under my direct supervision in accordance with the provisions of The Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual for the owners thereof." Mark D. Cevaal, P.E. Licensed Professional Engineer State of Colorado No. 33123 2 Date �pLANr) Final Drainage Report for The Learning Experience at Miramont Office Park Table of Contents General Location and Description.............................................................................4 Project Introduction............................................................................................. 4 ProjectLocation.................................................................................................. 4 SiteDescription...................................................................................................4 Floodplain Submittal Requirements.................................................................... 5 Drainage Basin and Sub-Basins...............................................................................5 MajorBasin......................................................................................................... 5 Sub Basin Descriptions......................................................................................5 Drainage Design Criteria...........................................................................................8 Regulations......................................................................................................... 8 Directly Connected Impervious Area(DCIA)....................................................... 8 Development Reference Criteria.........................................................................8 Hydrologic and Hydraulic Criteria........................................................................ 8 Floodplain Regulations Compliance.................................................................... 9 DrainageFacility Design........................................................................................... 9 GeneralConcept.................................................................................................9 SpecificDetails..................................................................................................10 Conclusion..............................................................................................................11 Compliance with Standards.............................................................................. 11 DrainageConcept.............................................................................................11 References.............................................................................................................12 Appendix A - Vicinity Map and Soils Map Appendix B - Hydrologic Drainage Calculations Appendix C - Hydraulic Drainage Calculations Appendix D - Reference Documents and Excerpts Appendix E - Proposed Drainage Plan 3 EDLAND Final Drainage Report for The Learning Experience at Miramont Office Park Project Introduction This PDP Drainage report for Lot 3 of the Miramont Office Park (the Site) covers the development of one 10,000 square foot building with parking and utility infrastructure. The proposed development will modify an existing detention pond to accommodate the new development and provide water quality. The site will be developed into a single story 10,000 square foot daycare building which will utilize an existing parking lot. Improvements include dry and wet utilities, curb and gutter modifications and the building. The building will be utilized as an early childhood development center with a playground. Project Location The project is located in the northeast quarter of Section 1, Township 6 North, Range 69 West of the 6th Principal Meridian in the City of Fort Collins, Larimer County, State of Colorado. See the Vicinity Map in Appendix A. More specifically it is located within the Miramont Office Park at the northwest corner of Boardwalk Drive and Oakridge Drive. The Site is bounded by existing office buildings to the north, Front Range Baptist Church to the west, Miramont Self -Storage to the south and Boardwalk Drive to the east. There are no major drainage ways or facilities on site. An existing detention pond for the Miramont Office Park is located on Lot 3 and will be modified with this development. Site Description Lot 3 of the Miramont Office Park is 1.614 acres. Currently the west half of the lot is developed as a parking lot with an access drive along the southern boundary. The east half has been overlot graded for a commercial building pad. An existing detention pond is located south of the pad site and serves the entire Miramont Office Park. The undeveloped portions of Lot 3 are covered in native weeds and grasses. The site has relatively mild grades (<2%) and no major drainage ways cross the site. The soils on site are Nunn Clay Loam which is Type C according the NRCS Soil Survey. Type C soils have slow infiltration rates when wet and have a slow rate of water transmission. The proposed site will be developed into a single story early childhood development center. 4 DLAND Ur Final Drainage Report for The Learning Experience at Miramont Office Park Floodplain Submittal Requirements The proposed Site is not located within the 100 year floodplain. Major Basin The project site is located within the City of Fort Collins McClellands Basin. No major drainage ways exist on site. According to the Final Drainage and Erosion Control Study of Miramont Office Park dated December 1997 the site is within Basin 202 of the McClelland's Basin Regional SWMModel. This basin includes the Miramont Office Park, Miramont Self Storage PUD, Front Range Baptist Church and Bank One at Harmony Market. Each of the four sites within this basin will need to provide on -site detention. Currently and in accordance with the Final Drainage and Erosion Control Study of Miramont Office Park on -site detention is provided at the southeast corner of the site. The site receives off -site flows from the church to the west. A swale along this property line collects these flows and directs them to the southeast access drive of the Office Park where they are released to Boardwalk Drive. Sub Basin Descriptions The overall drainage patterns, discharges and basin boundaries have not been modified from the Final Drainage and Erosion Control Study of Miramont Office Park. However, in order to accurately size the pond and associated structures the entire area tributary to the pond had to be analyzed. This analysis results in 10 basins: 7 tributary to the pond and 3 that direct flows off -site. Basin Al Design Point Area AC C2 C5 C700 11% Q 2 ear Q 100 Year Al 2.26 10.77 10.77 10.82 173.2% 13.75 113.93 Basin Al is the northern portion of the Office Park and is comprised mainly of the • developed Lots 1 and 2. This basin is fully developed and contains 4 existing commercial buildings and associated parking. Runoff sheet flows to curb and gutter where it is directed south to design point Al. Currently, a 6' curb cut directs these flows to the pond. This curb cut will be removed and replaced with a 15' Type R Inlet. This • inlet will direct the flows via a storm sewer to the modified detention and water quality pond. 5 LAIN qu-P -_ Final Drainage Report for The Learning Experience at Miramont Office Park Basin A2 Design Point Area AC C2 C5 C100 1% Q (2 ear) Q (100 Year A2 0.65 0.84 0.84 0.89 83.9 1.50 5.52 Basin A2 is the portion of the Lot 3 located west of the proposed building. This basin is fully developed and is comprised entirely of existing parking lot and landscaping. Runoff from this basin will sheet flow to the curb and gutter adjacent to the building. Currently, a two 2-foot wide curb cuts direct these flows to the pond at design point A2. These curb cuts will be removed and replaced with a 10' Type R Inlet. This inlet will direct the flows via a storm sewer to the modified detention and water quality pond Basin A3 Design Point Area AC C2 C5 IQ C100 1% (2 ear Q (100 Year A3 0.21 0.24 0.24 0.29 4.2 0.14 0.59 Basin A3 is the modified detention and water quality pond. This basin will remain landscaped. Runoff from this basin will sheet flow directly to the pond. Basin A4 Design Point Area AC C2 C5 C100 1% I Q (2 ear) Q (100 Year A4 0.13 0.28 0.28 0.33 9.7 0.09 0.38 Basin A4 is the playground located east of the proposed building. This basin will contain playground equipment and mulch for the childhood development center. Runoff from this basin will be captured in an underdrain along the eastern edge of the playground. This underdrain will divert the flows to the proposed storm sewer system at design point A4 where they will outfall into the modified detention and water quality pond. Basin A5 Design Point Area AC C2 C5 C100 1% Q (2 ear) Q (100 Year A5 0.11 0.95 0.95 1.00 90 0.30 1.11 Basin A5 is the west half of the proposed building's roof. Roof drains will collect flows from the roof and outfall the flow via storm sewer directly into the modified detention and water quality pond. 0 LI ALA Final Drainage Report for The Learning Experience at Miramont Office Park Basin A6 Design Point Area AC C2 C5 C100 1% Q (2 ear) Q (100 Year A6 0.11 0.95 0.95 1.00 90 0.30 1.11 Basin A6 is the east half of the proposed building's roof. Roof drains will collect flows from the roof and outfall the flow via storm sewer directly into the modified detention and water quality pond. Basin A7 Design Point Area AC C2 C5 C100 1% Q (2 ear) Q (100 Year A7 0.18 0.65 0.65 0.70 54.1 0.30 1.14 Basin A7 is the west half of the roofs of the two existing commercial buildings on Lot 2. Flows from this basin are directed to swale along the western property line that outfalls into a 2' curb cut at the northwest corner of Basin A2. This is an existing condition that is not changed by the proposed development. This runoff will sheet flow across Basin A2 and enter the new 10' Type R inlet at design point A2. Basin B1 Design Point Area AC C2 C5 C100 I% Q (2 ear) Q (100 Year B1 0.38 0.75 0.75 0.80 72.6 0.79 2.94 Basin B1 is the existing access drive along the southern property line of the Miramont Office Park. This access drive sheet flows undetained in Boardwalk Drive. This condition is unchanged from its description in the Final Drainage and Erosion Control Study of Miramont Office Park. Runoff from Front Range Baptist Church discharge into a swale that outfalls into the access drive as is discussed in the previous report as well. Basin B2 Design Point re Area C2 C5 C100 1% Q (2 ear__J Q (100 Year B2 0.76 0.76 0.76 0.81 72.5 1.27 4.71 Basin B2 is the west half of Boardwalk Drive and its adjacent right of way. A small portion of the on -site areas will sheet flow directly towards the right of way and be 7 D LAN[) u ..�1 Final Drainage Report for The Learning Experience at Miramont Office Park captured by the curb and gutter along Boardwalk Drive. These flows will be directed to the south. Basin B3 Design Point Area AC C2 C5 C100 1% Q (2 ear) Q (100 Year B3 0.06 0.67 0.67 0.72 62.2 0.10 0.39 Basin B2 is the south half of the shared access drive with Bank One. This basin will sheet flow undetained to the east and discharge into Boardwalk Drive and is unchanged by the proposed development. Drainage Design Criteria Regulations This report is in compliance with the City of Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual. Directly Connected Impervious Area (DCIA) Since the majority of the site is currently developed as a parking lot; therefore, incorporating directly connected impervious area and LID techniques is not required. The existing detention pond is being modified with the new development to remove the existing concrete low flow channel and replacing it with a grass swale to allow for some infiltration and sediment removal. The addition of the water quality control volume to the pond will also allow time for sediment and impurities to settle out of the runoff. Development Reference Criteria As previously mentioned, the Final Drainage and Erosion Control Study of Miramont Office Park dated December 1997 analyzes the drainage patterns for the site. The overall drainage plan and off -site conditions discussed in this report are still valid and are not changed by the proposed development. Hydrologic and Hydraulic Criteria Hydrologic and hydraulic analysis has been completed to meet the standards of the City of Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual as well as the Urban Drainage Flood Control District (UDFCD) Manual. The Rational Method was used to calculate the flows for each basin. Each basin was analyzed for different land uses and a composite coefficient and imperviousness was C CLAN (� Final Drainage Report for The Learninq Experience at Miramont Office Park calculated. 2 year run-off coeffecients were taken from Table RO-11 of the Fort Collins Criteria Manual and the frequency factors in Table RO-12 were applied to generate the 5, 10 and 100-year factors. Rainfall intensities for the one -hour storm are listed on Table RA-8 City of Fort Collins. These tables have been included in the appendix for reference. Design storm return periods are 2-year for the minor event and 100-year for the major event. The pond has been sized to detain the 10-year and 100-year storm events. The detention pond and its outfall structure were designed using LID _Detentionv2.32 from Urban Drainage and Flood Control District (UDFCD). The FAA Method was used to size the pond with a 10-year discharge of 0.2 cfs/acre and a 100-year discharge of 0.50 cfs/acre. These release rates were provided by the City of Fort Collins during their Conceptual Project Review. The storm sewer system for the Site is designed to convey the major event, while keeping the hydraulic and energy grade lines below finished grade. Emergency overflow routes have been designed to convey flows to the adjacent streets in the event an inlet becomes obstructed. All of the inlets on site were sized using LID _Inlet v3.12 from UDFCD to handle the 100-year flow without overtopping the adjacent curb and gutter. Ffoodplain Regulations Compliance No floodplains existing within the proposed study area. General Concept Stormwater in the office park will sheet flow southeast and be directed by curb and gutter to proposed inlets. These inlets will direct flows via storm sewer to the proposed pond. Discharge from the pond will be regulated through a two stage outlet structure that will outfall across the Miramont Self Storage Lot 2 to the south into a concrete drainage pan. This pan will direct the flows to Boardwalk Drive's curb & gutter. All areas tributary to the existing pond will be discharged into the revised pond. The revised pond has been sized to provide 10-year and 100-year detention plus water quality. DLAND Final Drainage Report for The Learning Experience at Miramont Office Park Specific Details The required storage for the detention and water quality pond has been calculated using the FAA method. In its existing condition, the pond has a 2 year release rate of 0.09 cfs and 100 year release rate of 1.80 cis. These flows were reduced to help compensate for the undetained flows from Boardwalk Drive and the Front Range Baptist Church per the Final Drainage and Erosion Control Study of Miramont Office Park. The release rates for the site as determined by the City of Fort Collins in the conceptual review were set at 0.2 cfs/acre for the 10-year event and 0.50 cfs/acre in the 100-year event. This results in a 10-year release rate of 0.73 cfs and a 100-year release of 1.83 cfs. These values are in line with the previous report and should have no negative impacts on downstream infrastructure The following table provides specific details about the detention and water quality pond. ' DETENTION/WATER QUALITY POND WQCV REQUIRED = 0.098 AC -FT WQCV PROVIDED 0.149 AC -FT 10-YR VOLUME REQUIRED 0.263 AC-FT+WQCV=0.361 AC -FT 10-YR VOLUME PROVIDED 0.435 AC -FT 100-YR VOLUME REQUIRED 0.577 AC-FT+WQCV=0.675 AC -FT 100-YR VOLUME PROVIDED 0.750 AC -FT WQCV WATER SURFACE ELEVATION 4999.00 10-YR WATER SURFACE ELEVATION 5000.90 100-YR WATER SURFACE ELEVATION 5002.59 OVERFLOW WEIR WATER SURFACE ELEV. 5002.59 10-YR ALLOWABLE RELEASE RATE - BASIN A 0.2 CFS\AC = 0.73 CFS 100-YR ALLOWABLE RELEASE RATE - BASIN A 0.5 CFS\AC = 1.83 CFS The proposed pond will have a two stage outlet structure with a water quality plate. The water quality plate will consist of one row of five 0.562-inch diameter holes. At the water quality water surface elevation, a 4.27 inch diameter hole will provide the 10 year release. This hole has been sized in conjunction with the water quality plate to restrict the release to 0.73 cfs when the pond is full to the 10-year water surface elevation. The top of the structure will be a single Type C Inlet located at the 10-year water surface elevation. This inlet will collect any volume greater than the 10-year. A restrictor plate has been sized over the structure's outlet pipe to reduce the flow to 1.83 cfs when the pond is full to the 100-year water surface elevation. The existing emergency spillway for the pond will be maintained. This spillway will provide relief for any volume over the 100-year volume in the pond or if the outlet structure becomes plugged. 1' of freeboard iics R�E DLAN Final Drainage Report for The Learning Experience at Miramont Office Park is provided above the spillway elevation. The City's FAA method spreadsheet was used to size the pond and can be found in the Appendix. A 12" RCP outfall pipe will service the outlet structure and convey the restricted flows to the south. The pipe will cross the access drive and a portion of Lot 2 Miramont Self Storage. The pipe will daylight into a 1' wide concrete drainage channel. This channel will direct the flows east under the existing walk and into the curb & gutter flowline of Boardwalk Drive. This outfall pipe falls within an existing 15' drainage and utility easement. Approval has been received from the owner of Lot 2 of Miramont Self Storage to complete the drainage improvements on the property, within the existing easement. A forebay will be provided for the 24" RCP pipe that outfalls into the pond at design point Al. This forebay has been sized to accommodate 1% of the WQCV for its tributary area. It will be 6" deep and discharge through a 4.2-inch wide rectangular weir at a flow equivalent to 2% of the 100 year discharge. The other pond outfalls do not require forebays because their tributary areas are too small. A copy of the UD_BMP spreadsheet for this design can be found in the Appendix. This sheet was only used for forebay design and the other elements remain blank. Maintenance access will be achieved via a gravel access drive along the southern end of the pond. The gravel access drive is graded not to exceed 10% and provides access from the existing driveway to the bottom of the pond and the outlet structure. Both the pond and outfall pipe will be located within the drainage easement on Lot 3 of Miramont Office Park. Compliance with Standards The intent of and computations within this report are in compliance with the City of Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual as well as the Urban Drainage and Flood Control District Criteria Manual. It follows the intent of the McClelland Basin Master Drainage Plan and has no impacts on any existing floodplains. Drainage Concept The proposed drainage concepts shown in the report have been design to create no negative impact on existing development or drainage facilities. The proposed improvements will contain storm runoff and discharge it safely and slowly during the design events. The proposed development is in conformance with the McClelland Basin Master Drainage Plan. 11 a!,1EDLAN � Final Drainage Report for The Learning Experience at Miramont Office Park 1. City of Fort Collins, City of Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual, latest online edition. 2. Urban Drainage and Flood Control District, Denver, Colorado, Urban Storm Drainage Criteria Manual, Volume 1-3, latest online edition. 3. The Sear -Brown Group, Final Drainage and Erosion Control Study Miramont Office Park, December 1997 12 PA DLAND Final Drainage Report for The Learning Experience at Miramont Office Park 13 L JL_ IL HARMONY RD > I CDR < C uj DRIVE McCLELLAND'S BASIN BOUNDARY North 17 Dam [jil Zi L L -VICINITY MAP i "=2000' LOCATED WITHIN McCLELLANDS DRAINAGE BASIN DATE 7.7.2013 VICINITY MAP PROJ. NO, 12026 PEDLANIF SHEET wf� G"em Pk� THE LEARNING EXPERIENCE 1H 11gem AT MIRAMONT OFFICE PARK Vic FORT COLLINS _CO_ C Hydrologic Soil Group—Lanmer County Area, Colorado (TLE Miramont) I� o 40" 31' 20' C C 494340 494370 494a00 494430 494460 4944e0 mw— I v o II m I I . T II I I I� n m I I I I o N I I I I e O _ f m � M1! Y N V p v N a vv NN P 494340 494370 404400 4Q4430 4Qd4fi(I 49449(1 • a Map Sole: 1:1.160 4 printed an A size (8.5" z 11") sheet. N Meters 0 10 20 40 6 .===Feet 0 40 80 160 240 • Natural Resources Web Soil Survey . d0i Conservation Service National Cooperative Soil Survey • 40' 31' 20" 40° 31' 12" 6/20/2013 Page 1 of 4 I(. 0 2 w 0 } « � lu \\,0 Si E LD \ }Eaz }0\c E k{7§ / EmE /f) k m ] afU■ E , A ! a0 m|_« | co) \ /{ A] 0 \m Cj 5\0 CD a » & f@� ■{3 o > G° ! 7;] { )4) iO 5 % <- a sm� _ »» & [£\{ \) L) E - \0aN �� `§ |) { )2E kk} \� �� - �# �(\ \\ k) \ ��— °r (d §)« g W§ \)« k� �\ }k \\ / Jkk /= }{\0 ( r —16! ; _ \ \ < ! ! £ ; \ Hydrologic Soil Group—Larimer County Area, Colorado TLE Miramont Hydrologic Soil Group Hydrologic Soil Group —Summary by Map Unit —Larimer County Area, Colorado (CO644) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 36 Fort Collins loam, 3 to 5 B 0.0 percent slopes 73 Nunn day loam, 0 to 1 C 4.3 percent slope Totals for Area of Interest 4.3 Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long -duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink -swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options 0.2% 99.8% 100.0% Aggregation Method: Dominant Condition USDA Natural Resources Web Soil Survey 6/20/2013 Conservation Service National Cooperative Soil Survey Page 3 of 4 C_ Hydrologic Soil Group—Larimer County Area, Colorado TLE Miramont Component Percent Cutoff.None Specfed Tie -break Rule: Higher USDA Natural Resources Web Soil Survey 6/20/2013 Conservation Service National Cooperative Soil Survey Page 4 of 4 ,u �,, 'J Final Drainage Report for The Learning Experience at Miramont Office Park 14 0 m O, e N N �' F- :` T pp CA r b 00 Q+ v�i �O l� N aF _M � m N M O p 8� r r t. V ONo O O O O o00 00 O O ' U N z4 V o 0 C. 0 o c Cl 0 0 0 0 C a h vl b o r4 y A � W y U a 00 l- Y o W A ="tn b _ E¢ U ry �D N- O O try r O N O iC O 1 U 7 O Q e•r e i rq C 0 0 0 . O 7 O �z � •w VJ r, r S nyj V1 (A Vl O e _ v 00 e p r e a 01 (ON 01 Cl Gzr W Or aaoo U o ooc O O14 z y _ U « - N O e C+ - ... - rJ 0 CA M 0 1� 0 z U U y A vr� N N CD e 0 0 0 0 0 Q N 0 0 0 0 N N W¢ CO CC�C- N O 41 0 0 0 0 ¢ O C p O C O N 7 - a' .¢ M V T C Ln O w w w w 00000 z �? Z cti zUxxx> wp¢a�¢�¢¢¢ _ mm awgm N M C U v LU OO,UUtL{ p�..a UU AM m= m' E.mQ rn � 8 r aQ0 N lmV Q Q b r h b O N N r O Q O v O m O �n O In O In O In O �p O r O Q C m N O m 0 0 NI O" m F � �m F wQ ,'Z U C N � Zu F Q e u e e e C � m O N P vl P Z f. A .a W� m Q Q .m m �o 0 yl � W .a � fV N fV fV fV Ci fV tV N Ca a F o 0 0 CD ❑ co u x I N N i .Yi (Ulm) ^ N c L 1j N A.LIJM3A C (v) _ - - 1117N3'I 1�!I:IZIS 3dld (%) F = UOIS i- - UPi\\Old g r; w W .91SW Q (SP)MO'73 W w 133H I.S F W A N a m MOIS V o 0 I�r to NO p r. I> a I " rn F a (V.J)S - (UIW)3I e c e �. Z y NO a o M H rv= n QW C O o 0 0 0 0 ('IQ�ui) �i L w 1 a N N N N N N N N N N F Q d O OG z (UIW)aj �c °NO m A n o 0 0 0 0S PC ._. _ ZJ ��3oJ h r N b P N r b o a W P h 3doNna (JV) y V3NV n o d o 0 0 o d o 0 N[SV8 "+ a << < a m m m s NOIS3a LNIOd a m m m N9IS3a 'a 3 �mm C F WHOJS c� W OoW < `o n�auu I m a Q N w a u!m ( J) _ w ABJO'I3A - e H1ONn = (i!) 3ZIS 3dld = a 3d07S F a. (S1J)M078 ;o W W NJIS3(1 Q (SMMOIJ W w .L33a1S v � O 4 'n M IS — C (S.IJ) � ry cl �z 4 a I M < P. G (iImN1 a mo a Z V1 NO aA a moo 000_�o P4/i0 z W 0 S a (JI �Q N m � ^ N O b r(Ulm) ZJ d3303 N b P N r n b O N m Off+ ° (JV) v3av P�o o0 000�00 x NISVII < a << 2 m m m c NOIS34 ` a ° o o Q 1NIOd N a `a i<< a 2 0o m m _ g NOISM ^ F ; w u IUa015 e ° g < ° o U U m Y C a N a UIIO O w „ N - - aiIJO-3n = (a) U19NAl (U!) 3ZIS 3dld (%) °' MOIS a F z (SMM01d e NDIS30 L7 E, (vla)MO'Id y. w y .L33a is in o v 3d07S W " 0. C O O (SIB) n N IF- i6 a .. d J i6 (J4N!) y W _z � 1 P 0 r O a- un e' F O a z a o N oro (Jwu!) pp o v� n a? o O r o r 0 r o n ry n P v LLCC^^ Q Q 1 r [O P P P P P P r 4V V ('s)•fj Q O (IIIW) J1 p m O m = fb1 S S S S g O n cc Q F r N b N N N — r oolO dd30J ee n m n � S n mo m ri p 7 c ddOMIV F V Vauv ��SS UU AEJ1IVII S30 6 b JXIOd N9[S30 ^ v Z Z = 3N17 a ` r W SUMMARY RUNOFF TABLE Basin Design Point Area AC C2 CS C100 1% Q 2 ear Q 100 Year Al Al 2.26 0.77 0.77 0.82 73.2% 3.75 13.93 A2 A2 0.65 0.84 0.84 0.89 83.9% 1.50 5.52 A3 A3 0.21 0.24 0.24 0.29 4.2% 0.14 0.59 A4 A4 0.13 0.28 0.28 0.33 9.7% 0.09 0.38 A5 A5 0.11 0.95 0.95 1.00 90.0% 0.29 1.07 A6 A6 0.11 0.95 0.95 1.00 90.0% 0.29 1.07 A7 A7 0.18 0.65 0.65 0.70 54.1 % 0.30 1.14 B1 B1 0.38 0.75 0.75 0.80 72.6% 0.79 2.94 B2 B2 0.76 0.76 0.76 0.81 72.5% 1.27 4.71 B3 B3 0.06 0.67 1 0.67 0.72 62.2% 0.10 1 0.39 Table RO-11 Rational Method Runoff Coefficients for Composite Analysis Character of Surface Runoff Coefficient Streets, Parking Lots, Drives: Asphalt 0.95 Concrete 0.95 Gravel 0.5 Roofs 0.95 Recycled Asphalt 0.8 Lawns, Sandy Soil: Flat <2% 0.1 Average 2 to 7% 0.15 Steep >7% 0.2 Lawns, Heavy Soil: Flat <2% 0.2 Average 2 to 7% 0.25 Steep >7% 0.35 (4) Anew Section 2.9 is added, to read as follows: 2.9 Composite Runoff Coefficient Drainage sub -basins are frequently composed of land that has multiple surfaces or zoning classifications. In such cases a composite runoff coefficient must be calculated for any given drainage sub -basin. The composite runoff coefficient is obtained using the following formula: n E (Ci * A; ) C = ;=1 Al Where: C = Composite Runoff Coefficient C; = Runoff Coefficient for Specific Area (A;) A; = Area of Surface with Runoff Coefficient of C;, acres or feet2 n = Number of different surfaces to be considered A,= Total Area over which C is applicable, acres or fete (5) Anew Section 2.10 is added, to read as follows: 41 (RO-8) 2.10 Runoff Coefficient Adiustment for Infrequent Storms The runoff coefficients provided in tables RO-10 and RO-I 1 are appropriate for use with the 2-year storm event. For storms with higher intensities, an adjustment of the runoff coefficient is required due to the lessening amount of infiltration, depression retention, evapo-transpiration and other losses that have a proportionally smaller effect on storm runoff. This adjustment is applied to the composite runoff coefficient. These frequency adjustment factors are found in Table RO-12. Table RO-12 Rational Method Runoff Coefficients for Composite Analysis Storm Return Period Frequency Factor Nears) C 2 to 10 1.00 11 to 25 1.10 26 to 50 1.20 51 to 100 1.25 Note: The product of C times C f cannot exceed the value of 1, in the cases where it does a value of I must be used (6) Section 3.1 is deleted in its entirety. (7) Section 3.2 is deleted in its entirety. (8) Section 3.3 is deleted in its entirety. (9) A new Section 4.3 is added, to read as follows: 4.3 Computer Modeling Practices (a) For circumstances requiring computer modeling, the design storm hydrographs must be determined using the Stormwater Management Model (SWMM). Basin and conveyance element parameters must be computed based on the physical characteristics of the site. (b) Refer to the SWMM Users' Manual for appropriate modeling methodology, practices and development. The Users' Manual can be found on the Environmental Protection Agency (EPA) website(http://www.epa.gov/ednnrmrl/models/swmm/index.htm). (c) It is the responsibility of the design engineer to verify that all of the models used in the design meet all current City criteria and regulations. 4.3.1 Surface Storage, Resistance Factors, and Infiltration Table RO-13 provides values for surface storage for pervious and impervious surfaces and the infiltration rates to be used with SWMM. Table RO-13 also lists the appropriate infiltration decay rate, zero detention depth and resistance factors, or Manning's "n" values, for pervious and impervious surfaces to be used for SWMM modeling in the city of Fort Collins. 42 (11) Section 4.0 is amended to read as follows: 4.0 Intensity -Duration -Frequency Curves for Rational Method: The one -hour rainfall Intensity -Duration -Frequency tables for use the Rational Method of runoff analysis are provided in Table RA-7 and in Table RA-8. Table RA-7 - City of Fort Collins Rainfall Intensity -Duration -Frequency Table for Use with the Rational Method (5 minutes to 30 minutes) Duration (min) 5 2-Year Intensity (in/hr) 2.85 10-Year Intensity (in/hr) 4.87 100-Year Intensity (in/hr) 9.95 6 2.67 4.56 9.31 7 2.52 4.31 8.8 8 2.4 4.1 8.38 9 2.3 3.93 8.03 10 2.21 3.78 7.72 11 2.13 3.63 7.42 12 2.05 3.5 7.16 13 1.98 3.39 6.92 14 1.92 3.29 6.71 15 1.87 3.19 6.52 16 1.81 3.08 6.3 17 1.75 2.99 6.1 18 1.7 2.9 5.92 19 1.65 2.82 5.75 20 1.61 2.74 5.6 21 1.56 2.67 5.46 22 1.53 2.61 5.32 23 1.49 2.55 5.2 24 1.46 2.49 5.09 25 1.43 2.44 4.98 26 1.4 2.39 4.87 27 1.37 2.34 4.78 28 1.34 2.29 4.69 29 1.32 2.25 4.6 30 1.3 2.21 4.52 33 Table RA-8 - City of Fort Collins Rainfall Intensity -Duration -Frequency Table for Use with the Rational Method (31 minutes to 60 minutes) Duration (min) 31 2-Year Intensity (in/hr) 1.27 10-Year Intensity (in/hr) 2.16 100-Year Intensity (in/hr) 4.42 32 1.24 2.12 4.33 33 1.22 2.08 4.24 34 1.19 2.04 4.16 35 1.17 2.0 4.08 36 1.15 1.96 4.01 37 1.16 1.93 3.93 38 1.11 1.89 3.87 39 1.09 1.86 3.8 40 1.07 1.83 3.74 41 1.05 1.8 3.68 42 1.04 1.77 3.62 43 1.02 1.74 3.56 44 1.01 1.72 3.51 45 0.99 1.69 3.46 46 0.98 1.67 3.41 47 0.96 1_64 3.36 48 0.95 1.62 3.31 49 0.94 1.6 3.27 50 0.92 1.58 3.23 51 0.91 1.56 3.18 52 0.9 1.54 3.14 53 0.89 1.52 3.1 54 0.88 1.5 3.07 55 0.87 1.48 3.03 56 0.86 1.47 2.99 57 0.85 1.45 2.96 58 0.84 1.43 2.92 59 0.83 1.42 2.89 60 1 0.82 1.4 2.86 34 Rt .�EDLAN� Final Drainage Report for The Learning Experience at Miramont Office Park 15 INLET IN A SUMP OR SAG LOCATION Project=__ __ TLE Miramont 412026 Inlet ID = Inlet 1-1 — Lb (C)- H-Cure H-Vert We W �Lo (G) al Inlet Inlet Type I Cepression (additional to mreinuous guiler depre norl'a trom'O.Allow) ev— bar of UnA Inlets (Grate or Curb Opening) No n Depth at Flewsrle (oursiae of local depression) Fording Depth e Information to of a Unit Grate 4 (G) h of a Unit Grate W. Opening Ratio for a Grata (typical values 0 15.0.90) A-. grog Factor for a Single Grate (typical value 0.50 - 0. 70) G (G) : War Coefficient (typical value 2.15 - 3 60) C, (G) • 1 Ordlce Coefficient (typical value 0 60 - 0 W0 C. (G) Owning Informatlon In of a Unit Curb Opening L. (C) 10 Vertical Curb Opening in Inches H.a a I of Curb Orifice Throat in Inches Fleas • s of Throat (see USDCM Figure ST-5) Theta Width for Depression Pan (typically iM ginner width of 2 feel) W. ping Factor for a Single Curb Owning (typical value 0. 10) Cr (C) Opening Weir Ccefflcietn (typical value 2.3-3.6) (% (C) Opening Orifice Coefficient (typical value 0.60 - 0 70) C. (C) it Inlet Interception Capacity (assumes clogged condition) O. ° MINOR MAJOR CDOT Type R Curb Opening 3.00 inches 2 6.0 6.0 Inches MINOR MAJOR OWiea WA Jim NIA feel WA WA WA WA WA 5.00 6.00 6.00 63.40 2.00 0.10 0.10 3.80 0.87 m uhes v;rm legreea sell 12026 UD4nlet v3 12 2013-06-21, Inlet In Sump &21I2013. 3:39 PM INLET IN A SUMP OR SAG LOCATION Project • TLE Miramont1112e26 Inlet ID = Inlet 1.2 (Base[ Al) — Lo (C) y H.Cure H Vert Wo WP \� `� W - - Lo (0) of Inlet Intel Type I Depression (adoitional to conlimmus gutter depression's' from'O-Allow) act„ oer of Unit Inlets (Grate or Cure Opening) No x Depth M Flowkne (Wrode of local depression) Pondinp Depth a Inforinstlon th of a Unit Grate Lo (G) h of a Until Grate Wa Opening Raho for a Grate (typical values 0,15-0.90) Aw,' ping Factor for a Single Grate (typical value 0.50 - 0 70) G (G) : s Weir CoeemJem (typical value 2.15. 3.60) C, (G) s Onfica Coeftlerd (typical value 060 - 0.60) C, (G) , ,Opening Irrtormanon th of a Unit Cure Opening L. (C) N of Vertical Cum Opening in Inches K. M of Cure OnOcs Throat in Incnes Hn,m s of Throat (see USDCM Figure ST-5) Thea. Width for Depression Pan (typically the puffer Width of 2 feet) Wp ping Factor for a Single Cure Opening (typical value 0.10) G (C) Opening Weir Coefficient (typical value 2.3-3.6) C. (C) Opening Onfca Coefficient (typical value 0.60 - 0.70) Co (C) tl Inlet Interception Capacity (assumes clogged condition) Q a Capaeitp .-. -e-i lur Storm. 110 PEAK) 0 .��• MINOR MAJOR COOT Type R Curb Openng 3.00 Inches 3 d.0 8.2 I iclies MINOR MAJOR Eo e'rx oeoms WA fem WA feet WA WA WA WA WA 5.00 6,00 &00 63.40 200 0.10 0.10 3.60 0.67 MINOR MAJOR set nches nches legmes eel 1'r26 Inlet 1 2 JDNetv2 2 _,13-0:>2' Net In Jump 62112013, 3:43 PM 10 Year 0 10-year Required detention W acre-ft. Composde'C' 0.74 11468.6 0.2633 Area 3.65 Modified Modified Release Rate 0.73 M. FATER D. JUDISH C. LI 5/95 Apr-98 Nov-98 DETENTION POND SIZING TIME TIME INTENSITY Q 10 Runoff Release I Required Required cum 10 year Volume Cum total Detention Detention (mins) (secs) (iNhr) (cfs) (ft"3) (ft"3) (ft"3) (ac-ft) 0 0 01 0.00 0 0.0 0.0 0.0000 5 300 4.8701 13.15 3946 219.0 3727.2 0.0856 10 600 3.780 10.21 6126 438.0 5687.9 0.1306 15 900 3.190 8.62 7755 657.01 7097.6 0.1629 20 1200 2.740 7.40 8881 876.0 8004.9 0.1838 25 1500 2.440 6.59 9886 1095.0 8790.7 0.2018 30 1800 2.210 5.97 10745 1314.0 9430.6 0.2165 35 2100 2.000 5.40 11344 1533.0 9811.2 0.2252 40 2400 1.8301 4.94 11863 1752.0 10110.8 0.2321 45 2700 1.690 4.56 12325 1971.0 10353.7 0.2377 50 3000 1.580 4.27 128031 2190.0 10612.7 0.2436 55 3300 1.480 4.00 13192 2409.0 10782.7 0.2475 60 3600 1.400 3.78 13613 2628.0 10985.0 0.2522 65 3900 1.320 3.57 13905 2847.0 11057.7 0.2539 70 4200 1.250 3.38 14180 3066.0 11114.3 0.2551 75 4500 1.1901 3.21 14464 3285.0 11178.9 0.2566 80 4800 1.140 3.08 14780 3504.01 11275.9 0.2589 85 5100 1.090 2.94 15015 3723.0 11291.9 0.2592 90 5400 1.050 2.84 15315 3942.0 11372.7 0.2611 95 5700 1.010 2.73 15550 4161.0 11388.7 0.2614 100 6000 0.970 2.62 15720 4380.0 11339.8 0.2603 105 6300 0.940 2.54 15995 4599.0 11396.3 0.2616 110 66001 0.910 2.46 16222 4818.0 11404.2 0.2618 115 69001 D. 2.38 16400 J 5037.01 11363.5 0.2609 120 72001 0.860 2.321 167251 5256.01 11468.6 0.2633 Page 1 100 Year C r C This is to convert % imp. to a C value 100 ar (must insert % imp. and Cpervious). Required detention ft acre-ft. 'C' value 0.79 Includes the Frequen Factor) Area 3.65 acres Modified Modified Release Rate 1.83 M. FATER D. JUDISF C. LI 5/95 Nov-97 Nov-98 DETENTION POND SIZING TIME TIME INTENSITY 0100 Runoff Release Required Required cum 100 ar Volume Cum total Detention Detention mina (secs) (infir) (cfs) (ft"3) ft"3) ft^3 ao-ft 0 0 0 0.00 0 0.0 0.0 0.0000 5 300 9.950 28.69 8607.248 549.0 8058.2 0.1850 10 6001 7.720 22.261 13356.37 1098.0 12258.41 0.2814 15 900 6.520 18.80 16920.38 1647.0 15273.4 0.3506 20 1200 5.600 16.151 19377.12 2196.0 17181.1 0.3944 25 1500 4.980 14.36 21539.75 2745.0 18794.7 0.4315 30 1800 4.520 13.031 23460.18 3294.0 20166.2 0.4630 35 2100 4.080 11.76' 24705.83 3843.0 20862.8 0.4789 40 2400 3.740 10.781 25882.3 4392.0 21490.3 0.4933 45 2700 3.460 9.98 26937.66 4941.0 21996.7 0.5050 50 30001 3.230 3300 3.030 9.31 27941.12 5490.0 22451.1 0.5154 55 8.74 8.25 28832.12 29688.52 6039.0 6588.0 22793.1 23100.5 0.5233 O5303 60 3600 2.860 65 3900 2.720 7.84 7.47 7.15 6.86 30588.17 31366.71 32179.861 32941.1 7137.0 7686.0 8235.0 8784.0 23451.21 23680.71 23944.91 24157.11 0.5384 0.5436 0.5497 0.5546 70 4200 2.590 75 4500 2.480 8D 4800 2.380 5100 2.290 85 6.60 6.37 6.141 33676.4 34411.69 35008.57 9333.0 9882.0 10431.0 24343.41 24529.71 24577.6 0.5588 0.5631 0.5642 90 5400 _ 2.210 95 5700 2.130 100 6000 2.060 5.94 35640.06 10980.0 24660.1 0.5661 105 6300 2.000 5.771 36332.1 11529.0 24803.1 0.5694 110 6600 1.940 5.591 36920.33 12078.0 24842.3 0.5703 115 6900 1.890 5.451 37603.72 12627.0 24976.7 0.5734 120 7200 1.840 5.311 38200.61 13176.0 25024.6 0.5745 125 7500 1.790 5.16 38710.99 13725.0 24986.0 0.5736 130 7800 1.750 5.05 39359.78 14274.0 25085.8 0.5759 135 81001 1.710 4.93 39939.36 14823.0 25116.41 0.5766 140 84001 1.670 4.821 40449.74 15372.0 25077.7 0.5757 145 8700 1.630 4.70 40890.91 15921.0 24969.9 0.5732 150 9000 1.600 4.61 41522.4 16470.0 25052.4 0.5751 155 9300 1.570 4.531 42101.98 17019.0 25083.0 0.5758 160 9600 1.540 4.441 42629.66 17568.0 25061.7 0.5753 165 9900 1.510 4.35 43105.44 18117.0 24968.4 0.5737 170 10200 1.480 4.27 43529.32 18666.0 24863.3 0.5708 175 10500 1.450 4.18 43901.29 19215.0 24686.3 0.5667 180 10800 1.420 4.09 44221.361 19764.0 24457.4 0.5615 185 11100 1.400 4.04 44809.59 20313.0 24496.6 0.5624 190 11400 1.380 3.98 45363. -5 20862.0 24501.2 0.5625 195 11700 1.360 3.92 45882.2 21411.0 24471.3 0.5618 200 12000 1.340 3.861 46366.68 21960.0 24406.7 0.5603 205 12300 1.320 3.811 46816.51 22509.0 24307.5 0.5580 210 12600 1.300 3.75 47231.73 23058.0 24173.7 0.5550 215 12900 1.280 3.69 47612.35 23607.01 24005.4 0.5511 220 13200 1.260 3.63 47958.37 24156.0 23802.4 0.5464 225 13500 1.240 3.58 48269.79 24705.0 23564.8 0.5410 230 13800 1.220 3.52 48546.61 25254.0 23292.6 0.5347 235 14100 1.210 3.491 49195.39 25803.0 23392.4 0.5370 240 14400 1.200 3.46 : 49826.88 26352.0 23474.9 0.5389 Page 2 Project: TLE AT Miramont Basin ID: o,� _sW Skr.z w. ubsk,z STAGE -STORAGE SIZING FOR DETENTION BASINS sw wpz Dv. Wv �. •---------y-"-'-- -> Sae SIMZ 5W 91rea a. W \ L \ Deaipn Infirmation (Input): Check Basin C- Width of Basin Bottom, W =�fl Right Triangle Length of Basin Bottom, L ft Isosceles Triangle Dam Side -slope (HAO, Z, ft/R Rectangle C. Circle / Ellipse Irregular Storage Requirement from Sheet'Modi0ed FAA': Stage -Storage Relationship: Storage Requirement from Sheet'Hydrograph': Storage Requirement from Sheet'Full-Spectrum': Sha OR... OR... OR... OR... (Use Ovende values in cells G32:G52) MAJOR 0.62 acre-ft. acre-ft. acre-ff. MINOR 0.27 C Labels for WOCV, Minor, & Major Storage Stages (input) Water Surface Elevation If Side Slope (H:V) n/ft Below El. -out) Basin Width at Stage It (owl Basin Length at Stage It (output) Surface Area at Stage fe out. r Surface Area at Stage ft' User Overide Volume Below Stage ft' (output) Surface Area at Stage acres (output) Volume Below Stage acre-ft (output) Target Volumes for WOCV, Minor, & Major Storage Volumes for goal seek) 4997.00 0.00 0.00 D.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 0.000 0.000 0.039 0.149 WCOV-0.098 4998.00 3396 1,698 0.078 WOCV 4999.DO 6177 6,485 0. 142 _ 9,621 0.146 12.857 0.151 18,931 0.159 19,625 0.160 26,982 0.178 32.672 0.265 44,328 0.265 #N/A #N/A _ #N/A I *NIA #NIA 4999.50 6,368 0.221 5000.00 6,575 0.295 Minor 5000.90 6,923 6,967 7,747 11,541 0.435 10 YEAR=.43 5001.00 0.00 _ 0.60 0.451 5002.DD [-DO _ 0.00 U19 Major 5D02.59 0.00 0.00 _ 0.00 0.00. -- 0.750 100 YEAR - .719 5003.60 11,541 1.018 #N/A #N/A _- #NIA *N/A *N/A *N/A *WA #WA *N/A #WA *N/A #NIA #WA #NIA lfW/A #N/A #WA #WA #WA #WA #N/A #WA #N/A *N/A #N/A *N/A *N/A #N/A *WA *N/A Ili #NIA #WA #WA #WA R4/A #N/A #NIA #N/A #WA _ #N/A #NIA #WA #NIA #WA #N/A #WA #WA *N/A #WA #WA #WA #WA #N/A #WA #WA #WA #WA #WA *N/A #WA #NIA #WA 12026 LID -Detention v2.32 FINAL. Basin 101112013, 2:09 PM STAGE -STORAGE SIZING FOR DETENTION BASINS Project: Basin ID: STAGE -STORAGE CURVE FOR THE POND 5004.08 5003.08 - rt 5002.08 j 5001.08 d d m >A 5000.08 4999.08 - - -- -- 4998.08 - 4997.08 0.00 020 0 40 0 60 0.80 1.00 120 Storage (acre-feet) 12026 LID-Deten6on_v2.32 FINAL, Basin 10/1/2013, 2:09 PM ƒ) §\7 !! -. :. . § ( 0 0 0 0 (naja 'jaaJ) a6e7S RESTRICTOR PLATE SIZING FOR CIRCULAR VERTICAL ORIFICES Project: TLE at Miramont #12026 Basin ID Sizing the Reatrictor Plate for Circular Vertical Orifices or Pipes flnoutl Water Surface Elevation at Design Depth PipeNeiliral Onfice Entrance Invert Elevation Required Peak Flow through Office at Design Depth PipeNerfiral Orifice Diameter (inches) Onhce Coefficient Full -flow Cae aclN fCalculatedl Fuii-flow area Half Centrat Angle in Radians Full -flow rapacity Calculation of Orifice Flow Condition Halt Central Angle (0<Theu ,3.1416) Flow area Top width of Onfice (inches) Height from Invert of Orifice to Bottom of Plate (feet) Elevation of Bottom of Plate Resultant Peak Flow Through Orifice at Design Depth Width of Equivalent Rectangular Vertical Orifice Centroid Elevation of Equivalent Rectangular Vertical Orifice Elev: WS Elav: Invert O Die C. icalce.59305 M 54,9W.97 eel eet Ys rches At 0.79 sq it Theta = 3.14 red Of = 9.3 cfs Percent of Design Flow= 508% Theta = A. = T. = Y, = Elev Plate Bottom Edge = aq cadtt inches feet feet ds Equivalent Widths 0.60 _feet Equiv. CeMroltl EI, a 4,997.10 feet 1.04 D.15 10.32 0.25 4,997.22 LB 12026 UD-Detenbon_v2.32 FINAL. Restrictor Plate 1011/2013. 2:09 PM STAGE -DISCHARGE SIZING OF THE WEIRS AND ORIFICES (INLET CONTROL) Project: TLE at Miramont #12026 Basin 10: Rawrntl CFJer ul (alnrWnll NUWinX t)rtlo��l ¢-XtL 994 'ram iNV Rwwq Caa19} lR&Pgb aYpl zi4�?T ean_.o Current Routing Order Is #2 �(��--- Design Information flnalrtl: Circular Opening Diameter in Inches OR Rectangular Opening: WeBh in Feet Length (Height for Vertical) Percentage of Open Area After Trash Rack Reduction Onfice Coefficient Weir Coefficient Orifice Elevation (Bottom for Ver ice0 Calculation of Collection CaoacHv: Net Opening Area (after Trash Rack Reduction) OPTIONAL User-Ovende Net Opening Area Penn eler as Weir Length OPTIONAL: User-Ovende Mir Length _va �.Yumy_ xm,q owY #1 Horiz. 02 Honz #1 van #2 Van. Dia. 1 4.27 inches W = 2.92 0.80 It L er H = 2.92 0.25 ft. % open % Co C. = ft Ao= 426 0.10 015 s0. ft A,= sq ft. L. = 876 ft. L. ft. Top Elevation of Vemcat On6ce Opening, Top - 4999,36 4997.22 It Center Elevation of Vertical Onfice Opening, Con . 4999AS 4997.10 ft. 50 1 700 100 0.85 0.85 0.85 3.00 5000.90 4999.00 4,998.97 Routing 2: Water flows through WQCV plate and #1 vertical opening and #1 horizontal opening Into 02 vertical opening (#2 horizontal opening is not used). I Horizonte l Orifices IVertieal Orifices I .¢x5 .... ,,V. Minor a Ma1or st. a W S Elevalrore f:p'h Water Surface Elevation ft WQCV Plate/Riser Flow cis #1 Honz. #1 Honz. Weir OnrKA Flay Flow cis CIS I 02 Honz #2 Honz. Weir Orifice Flaw Flaw eb els t 0u tl #1 Vert. Collection Capacity ef5 %"' i' #2 Ven. Collection Capacity CIS JUI I Total Collection capacity Cis Te1ge1 V0U.m lo' WCCV Mcci S Maior slora9e Volumes 4997.00 0.00 000 0.00 0.00 0.00 0,00 0.01 0.00 4998.00 0.00 0.00 0.00 0.00 0.00 0.M 0.74 0.00 tArOOV 4999.00 0.01 0.00 0.00 0.00 0.00 0.00 1.08 0.01 vvcicy 4999.50 0.02 0.00 0,00 0.00 0.W 0.29 1.21 0.32 5000.00 0.04 0.00 0.00 0.00 0.00 0.47 1.33 0.51 Mirror 5000.90 005 0.00 0.00 0.00 0.00 0.68 1.53 0.73 10 ear 5001.00 0.06 0.83 7.03 0.00 0.00 0.70 1.65 1.55 5002.00 0.06 30.32 23.32 0.00 0.00 0.87 1.73 1.73 Major 5002.59 007 57.74 28.91 0.00 0.00 0.95 1.53 1.93 s illwa I1OO r 5003.60 0.08 116.59 36.54 0.00 MOD 1.09 2.00 100 008 #WA MIA MIA MIA MIA MIA MIA 0.09 MLA MA ALA MIA MIA MLA MLA 0.09 MIA MLA #WA MIA MIA MIA MIA MIA MIA MLA NWA MIA r MIA MA MA AWA #NIA #WA MIA OWA MIA NWA MIA MA MA MLA MIA MIA #WA #WA MIA *N/A ALA MIA MIA MLA #WA NWA MLA M/A MA #WA ALA MIA ALA MLA #WA MA MIA MIA MIA ALA MA MA MIA ALA #NIA ALA ALA ALA MA ALA MIA ALA ALA ALA #WA MIA *WA _ #WA #N/A MIA MIA MA ALA *N/A #N/A MLA #WA MLA MLA MIA ALA ALA ALA .ALA MIA MLA ALA MIA *WA MLA #WA MIA NWA MIA #WA #NIA #WA #WA MA _ *N/A #NIA MIA #N/AALA MIA - NWA**MWA MLA A1/A MIA MM MIA MIA MIA MIA MIA ALA M/A NWA ALA MIA #N/AAWA MIA ALA MIA MIA #WA 0iALA *N/A MIA ALA ALA ALA MLAALA ALA MIA #N/A ALA MLA NWAMIA MIA MLA MIA #WA MLA MIAMAMIA MA MIA MA MIA MA MIAMA #N/A MIA MA MA *N/A MLAMLA MA MA #WA MA MA #WAMIA MIA MIA MIA MA MLA 0WA MLA ALA MIA MIA M/A MIA M/A MLA #WA #WA MIA #WA MA MIA _' M/A #WA #WA MA NWA I MIA MIA MIA MIA MIA MIA MIA #WA MIA ALA MIA #NIA #WA *N/A #WA #WA MLA NWA MLA MIA MIA MA MIA MLA ALA MIA MIA MLA MLA #WA MLA MA ALA MIA MLA MA MLA #NIA MA MIA MIA ALA #WA MIA #WA ALA ALA 2O26 UD-Detention v2.32 FINAL, Outlet 10/12013, 2:09 PM STAGE -DISCHARGE SIZING OF THE WEIRS AND ORIFICES (INLET CONTROL) Project: TILE at Miramont #12026 Basin ID: STAGE -DISCHARGE CURVE FOR THE OUTLET STRUCTURE 5004.08 — — -� i 5003.05 5002.08 — I m ! 5001.08 - - — d R 47 I 5000.08 — -- — - - - 4999.08 — - -- — - - - - - - 4998.08 I -, 4997.08 - -- - - -- -- 0 0.5 15 _ 25 Discharge (cfs) 12026 LID -Detention v2.32 FINAL, Outlet 10/12013. 209 PM STAGE -DISCHARGE SIZING OF THE SPILLWAY Projeet: TLE at Miramont Basin ID: Existing Spillway Capacity aM c ayWmN vY wyy u,. •lat C.lLST Design Information (input): Bottom Length of Weir Angle of Side Slope Weir Elev. for Weir Crest Coef. for Rectangular Weir Coef. for Trapezoidal Weir Calculation of Spillway Capacity (output): L = 6.00 feet Angle = 75.96 degrees EL. Crest= 5,002.59 feet C„. = 3.30 C = 2.50 Water Surface Elevation ft. nked) Red. Weir Flowrate ds ((output) Triangle Weir Flowrete ds out LL' Total Spillway Release ds (output) Total Pond Release ds (output) 4997.00 0.00 0,00 0.00 0.00 4998.00 0.00 0.00 0.00 0.00 4999.00 0.00 0.00 0.00 0.01 4999.50 0.00 0.00 0.00 0.32 5000.00 0.00 0.00 0.00 0.51 5000.90 0.00 0.00 0.00 0.73 5001.00 0.00 0.00 0.00 1.55 5002.00 0.00 0.00 0.00 1.73 5002.59 0.00 0.00 0.00 1.83 5003.60 20.10 10.25 30.35 32.35 #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A MIA #WA #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #NIA #WA #N/A MIA #N/A #N/A #N/A #N/A #NIA MIA *N/A #WA #N/A #N/A MIA #N/A #N/A #N/A #NIA #N/A #N/A #NIA #N/A #N/A #N/A #NIA #WA #N/A MIA #NIA #N/A #N/A #N/A #N/A #N/A #N/A #N/A MIA #N/A MIA #N/A #N/A #N/A MIA #N/A MIA *N/A #N/A #N/A MIA MIA #N/A #N/A #N/A #NIA #N/A #NIA #N/A #N/A #N/A #N/A #N/A #NIA #N/A MA #N/A #N/A #N/A MIA #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A MIA MIA #WA *N/A #N/A #N/A MIA #N/A *N/A #N/A #N/A MIA #NIA #N/A #N/A #N/A MIA #N/A #N/A #WA #N/A #N/A #N/A #NIA #N/A #N/A MIA #N/A #N/A #NIA MIA MIA #N/A #N/A *N/A MIA #N/A #N/A MIA #WA #N/A *N/A #N/A #N/A #WA #N/A #N/A MIA #N/A #WA #N/A #N/A 1 #N/A #N/A #N/A #N/A #N/A #NIA #N/A #WA *N/A #N/A #NIA MIA 12026 UD-Detention_v2.32 FINAL, Spilhaay 10/1/2013, 2:09 PM STAGE -DISCHARGE SIZING OF THE SPILLWAY Project: TLE at Miramont Basin ID: Existing Spillway Capacity STAGE -STORAGE -DISCHARGE CURVES FOR THE POND Storage (Acre -Feet) 0 0.2 0.4 06 08 1 12 5004 5003 4 0. Lm 000 OA ro 100 _ 5002 i m m a� 5001 r_ m a to 5000 4999 4998 4997 0 5 TO 15 20 25 30 35 Pond Discharge (cfs) T IOt4 ROMipL T®LLNMY pY.MYAE ��ICM IIgNOF 12026 UD-Detention_v2.32 FINAL, Spillway 10/1/2013, 2:09 PM c ( FD�igner: Location: Design Procedure Form: Extended Detention Basin(EDB) TJF Redland July 8, 2013 TLE Mlramont Basin 1 and 4 Forebay Design 1 of 1 Basin Storage Volume A) Effective Imperviousness of Tributary Area, I, Ia = 69.7 8) Tributary Area's Imperviousness Ratio (i = I,/ 100) 1 = D.697 C) Contnbuting Watershed Area Area = 2.390 ac D) For Watersheds Outside of the Denver Region. Depth of Average de = in Runoff Producing Stomp Choose One E) Design Concept (Select EURV when also designing for flood control) (Diviner Quality Capture volume (WQCV) (:�Ucess Urban Runoff Volume (EURV) F) Design Volume (1.2 WQCV) Bati on 40-hour Drain Time Vxais�- 0.055 ac-fl (VDEsica = (1.0' (0.91 - 1'- 1.19 - i- • 0.78' i) / 12' Area' 1 2) (3) For Watersheds Outside of the Denver Region, VDEsiGe OTrEa= ac-fl Water Quality Capture Volume (WQCV) Design Volume (V...,.Ee = (cI.'(Voesiar✓0.43)) H) User Input of Water Quality Capture Volume (WQCV) Design Volume VDESIGH uses= aolt (Only I a different WQCV Design Volume is desired) Choose One 1) Predominant Watershed NRCS Sol Group OA 08 CSC/0 J) Excess Urban RmmOff Volume (EURV) Design Volume For HSG A. EURVA = (0.18781- 0.0104)'Area EURV = ac-f t For HSG B. EURVs = (0, 1178ii - 0.0042)'Ama For HSG CID: EURVi c = (0 1043i - 0.0Q31)'Area 2. Basin Shape Length to Width Ratio L W = 2.0 (A basin length to width ratio of at least 2:1 will improve TSS reduction. ) 3 Basin Side Slopes A) Basin Maximum Side Slopes Z = 4.00 H i it (HOMontal distance per unit vertical , 4'1 or flatter preferred) 4 Inlet AI Describe means of providing energy dissipation at concentrated r'I,'n.\ IOG'lnc;rc UD-BMP for Basin 1 and 4, EDB 7/8/2013, 3:42 PM Design Procedure Form: Extended Detention Basin (EDB) Sheet 2 of 4 Designer TJF Company: Redland Date: July 8, 2013 Project: TLE Mlramont Location: Basin 1 and 4 Forebay Design 5. Forebay A) Minimum Forebay Volume VFM,m = 0.001 ac-ft (VFem = 1% of the WQCV) B) Actual Forebay Volume VF = ac-ft C) Forebay Depth DF = 6.0 in (Dr = 12 inch maximum) D) Forebay Discharge i) Undetained 100-year Peak Discharge 01. = 14. 74 cfs in Forebay Discharge Design Flow Qr = 0.29 cfs (%= 0,02' Qmo) E I f-crecoy Discharge Design Choose One f c8erm With pipe (flow too small for berm wf pipe) *Nall with RM. Notch ()Wall with V-Notch Weir GI Rectangular Notch Width Calculated W. = 4.2 in Choose One 6. Trickle Channel aonnete A) Type of Trickle Channel $oft action F) Slope of Trickle Channel S = it / ft 7 Micropool and Outlet Structure A) Depth of Micropool (2 5-feet minimum) DM = If B) Surface Area of Microcool (10 ft° manimum) Am = sq It C) Outlet Type Choose One I�tt�nbe): D) Depth of Design Volume (EURV or 1.2 WQCV) Based on the Design Concept Chosen Under 1.E. E) Volume to Drain Over Prescribed Time F) pain Time (Min To for WQCV= 40 hours: Max To for EURV= 72 hours) G) Recommended Maximum Outlet Area per Row. (A,) H) Onfice Dimensions: i) Circular Orifice Diameter or 1) Number of Columns J) Actual Design Outlet Area par Row (A,) K) Number of Rows (ril L) Total Outlet Area (Ao) H = feet WQCV = ac-ft To= hours A.= square inches D„,,,„= inches h = number A,= square inches n,= number A. = square Inches UD-BMP for Basin 1 and 4, EDB 71812013. 3.42 PM Design Procedure Form: Extended Detention Basin (EDB) Sheet 3 of 4 Designer: TJF Company: Reciland Date: July 8, 2013 Project: TILE Miramont Location: Basin 1 and 4 Forebay Design 8 Inital Surcharge Volume A) Depth of Initial Surcharge Volume (Minimum recommended depth is 4 inches) B) Minimum Initial Surcharge Volume (Minimum volume of 0.3% of the WQCV) C) Initial Surcharge Provided Above Micropool 9. Trash Rack A) Type of Water Quality Orifice Used B) Water Quality Screen Open Area: A, = 38.5'(e-0')-A. D) For 2" High Rectangular Openlna I) Width of Rectangular Opening if) Width of Water Quality Screen Opening (W,) III) Height of Water Quality Screen (Fin,) iv) Type of Screen, Describe d "Other' v) Cross -bar Spacing vq Minimum eeanng Bar Sae D, = in V,s = cu it V,= cu it ,Choose One ()Circular (up to 2" diameter) Olectangular (2" high) A,= square inches I (DS.S. Well Screen with 60%Open Area• 0Dtner (Describe): W = inches Ha= it One [Choose, QAluei Amco-Kkmp SR Series (or equal) COther (Describe): inches UD-BMP for Basin 1 and 4. EDB 7/812013, 3:42 PM 11 Design Procedure Form: Extended Detention Basin (EDB) 11 Designer: TJF Company: Redland Date: July 8, 2013 Project: TLE Miramont Location: Basin 1 and 4 Forebay Design 10 Overflow Embankment A) Describe embankment protection for 100-year and greater overtopping: B) Slope of Overflow Embankment (Ho=ntal distance par unit vemCal, 4.1 or flatter preferred) Z, = ft / ft '1 Vegetation QlmgatN CNot tmgated 12. Access AI Describe Sediment Removal Procedures :ate, • UD-BMP for Basin 1 and 4, EDB • 7/812013, 3:42 PM Pr AUE DLAIN Final Drainage Report for The Learning Experience at Miramont Office Park Appendix D - Reference Documents and Excerpts 16 v =1� C'0 -Final A 0 00 �1r . 3 o Repod fe L .- 0 0 Final Drainage and Control Study C�0 O o o f i) O 0 Nwamont Office Park Q Fort Collins, G/olorado :1 o o D0 o O 0 . •� CD a • December, 1997 • ' THE • 1 SM.-BROWN • GROUP • • Standards in Excellence • ttnoft'icial copy was downloaded at Sep-10.2012 from the City of Fort Collins Public Records Website: hltp:/Jcitydocs.fegov.com • or additional information or anofficial copy, please contact Cityof Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA TeRi �' OF COIF PAGE nFCCRipTION GENERAL LOCATION AND DESCRIPTION t Location 1 Description of Property ' DRAINAGE BASINS 1 Major Basin Description I Sub -Basin Description DRAINAGE DESIGN CRITERIA 3 Regulations 3 Development Criteria Reference and Constraints 3 Hydrologic Criteria 3 Hydraulic Criteria 3 Variances from Criteria DRAINAGE FACILITY DESIGN 4 General Concept 4 Specific Details STORM WATER QUALITY 5 General Concept ' EROSION CONTROL 5 General Concept 5 1 Specific Details CONCLUSIONS Compliance with Standards 6 6 Drainage Concept 6 6 Storm Water Quality Erosion Control Concept 7 REFERENCES is unofficial copy toss downloaded on Sep-10-2012 from the City of Fork Collins Public Accords Website: http://ciins Co80524 US _ _ _ _ sC.,.iat ennv. nlease contact City 0f Foil Collins Utl6ties 700 Wood Stroet FOtt COlitns, C80524 US ' FINAL DRAINAGE AND ' EROSION CONTROL STUDY FOR THE MIRAMONT OFFICE PARK FORT COLLINS, COLORADO A. Lncanon The Miramont Office Park is located south of Harmony Road between Boardwalk Drive and the Fairway Estates Third Filing. It can also be described as being north of the Upper Meadow at Miramont First Filing P.U.D. and the proposed Miramont Self -Storage P.U.D. More specifically, this site is located in the Northeast Quarter of Section 1, Township 6 North, Range 69 West of the 6th principal Meridian, City of Fort Collins, Larimer County, Colorado- B. R01dotion of Proue U The Miramont Office Park site is currently undeveloped and sparsely covered with grade of natural ground vegetation. The site slopes from north to south at unde stood approximately I %. The proposed purpose for the subject site is currently to be for a privately owned and operated office park. II. nusnvA('F' BASINS • A. N Rain Description The project site is located within the McClellands Basin, SWMModeled as Basin 202. No major drainage way exists within the Miramont Office Park site. ' B. Cnh Basin Descrtntion As stated, the Miramont Office Park lies within Basin 202, as laid out in the McClellands Basin Regional SWMModel. Basin 202 also contains the proposed ptist Church ne at Miramont armony Market. The completion of thRangeorage P.U.D., Front project aevwill partially develop Basin d Bank H 202. Detention for Basin 202 is provided by on -site ponds - one for each of the four sites. The Miramont Office Park will provide an on -site detention pond in the southeast corner of the site. 1 is unofficial copy was downloaded on Sep.10 2012 from City of Fort Collins Ut IifFics 00 Wood Stbrect FortpCorllinsC O 80524 OS nt Range This site will be receiving flows from the future detentionreleases on the Froater onto the Church, to the west. Currently, the church ' Baptist property that is planned for the office park. The Bank One at Harmony Market P.U.D. site to the north of the office park will When the Bank One drainage report release its detained runoff to Boardwalk Drive. by Meline & n, Inc. it planned for a swale (Section G-G) starting Irela was submitted at the southwest corner of their property. This swale was designed to carry the around the Bank One site. When the Front Range Baptist Church's historic runoff Church access drive plan and profile was approved earlier this year, this swale was The has been constructed, and connected to a culvert under the access drive. culvert now discharges into a Swale with a similar cross-section, which releases onto the office park site. Since the Miramont Office Park is in the flow path of the historic drainage path for to deflect flow around the office park Front Range Baptist Church, it was necessary that it would still reach Boardwalk. A continuation of the Swale designed with the so Bank One site has been proposed along the east property line of the church to carry and then release it into the Miramont Office the church's historic runoff to the south, drive is integral not only to the office park Park south access drive. Since this access but also the Miramont Self -Storage Units, it imposes grading cross - and the church, restrictions on all the sites. In order to drain the church's runoff into Boardwalk the drive, it was necessary to ' Drive without intercepting it between the swale and plan for this driveway to free release into Boardwalk Drive. An easement from Front Range Baptist Church has been obtained for the proposed swale. The undetained flow from the Front Range Baptist Church, along with release from Boardwalk Drive and will be captured the Miramont Office Park site will flow along in the Detention Pond at Lemay and Boardwalk. Due to grading restrictions, Basins 5 & 6 release undetained onto Boardwalk Drive. The allowable 2 year release rate The rate has been decreased to 0.09 cfs/acre for this project is 0.12 cfstacre. release in order to detain as much run off as possible in light of the fact that Basins 5 & 6 run an additional 0.53 cfs enters off undetained. Even with the decreased release rate, Boardwalk Drive during the 2 year storm. An orifice plate controls flow from the will pond at the decreased rate up to the 10 year WSEL. At this point, water and discharge at the 100 year rate of 0.5 cfs/acre. overflow into the release structure During the 100 year storm event, the site is releasing 2.39 cfs more than is allowed require any additional storage per the Master Plan. This additional release will not downstream detention pond #180, SWMM conveyence elementl in the allowable flows of 120 cfs are not exceeded, (see SWMM calculations in appendix) by RBD, Inc. in nor are street capacities being exceeded. According to calculations the capacity of Boardwalk Drive (south half) are 8.39 cfs for the August 1994, street 2 year storm and 70 cfs for the 100 yr storm. From revisions to the calculations for 2 2 froni the City of is unofficial copy was dmvnloadod on �p'l1 con City of Fort Collins Utilllins ities 00 Wood Slmlic. Records et For' Collins Co 80524 USA or additional information or an official copy, Please ' flow in Boardwalk Drive (see appendix) that takes into account the undetained runoff from Basins 5 & 6, the 2 year and 100 year flows are 6.43 cfs and 23.18 cfs respectively; both below street capacities. Per meetings with Stormwater Utility, the additional release during the 2 and 100 year events would be permitted as long as street capacities are not exceeded and the available downstream detention pond ' volume is sufficient. III- �e nv a r_F nFSIGi�i CRITERIA. A. Re¢ul�at M ' The City of Fort Collins Storm Drainage Design Criteria is being used for this subject site. B. peveionment tit riauaso.�..�n ned Cans ints As stated earlier, flows from the site are detained on -site in a pond. Basin 202, as shown on the Overall Drainage Plan for the McClellands Basin, had only one pond within it, but the individual property owners have elected to prorate the detention requirements so that each of the pieces have their own detention ponds. Basin 202 was originally modeled with an impervious percentage of 50.00%. ' C. Hydroloaie Criteria The Rational Method is being used to determine run-off peak flows from the study site. Rainfall criteria for this study was obtained from the City of Fort Collins and is included in the Appendix. The 2- and 100-year rainfall criteria were utilized to determine the developed flows. The release rate from the pond was obtained by proportioning the acceptable release rate from Basin 202 on a per -acre basis, and then applying that figure to the Miramont Office Park site area. D. Hydraulic d eria All calculations within this study have been prepared in accordance with the City of Fort Collins Drainage Criteria. E. Va QlcPe from riteria A variance of 2.39 cfs from the allowable site release for a 100 year storm event is being sought for Basins 5 & 6 which drain undetained into Boardwalk Drive because of site grading restraints. 3 his unofficial copy was downloaded on Sep-10-2012 from the City of Fort Collins Public Records Website: httpJ/citydocs.lcg0v wm is :..r m.atinn or an official copy, Please contact City o--ort Collins Utilities 700 Wood Street Fort Collins, CO 80524 US s. KI - _aI&II-M-Cel ' A. General Concept Stormwater for the office park site will sheet flow southward across the parking lots and be directed by curb & gutter to sidewalk culverts. The sidewalk culverts discharge the flow into the detention pond. Discharge from the detention pond will be regulated through a staged release structure attached to a 15-inch HDPE drain pipe. The drain pipe will terminate at a concrete chute that will carry the flow into a metal covered sidewalk culvert. The sidewalk culvert discharges the on -site flow into the flowline of Boardwalk Drive, as indicated in the Master Plan. B. Specific Details The required storage for the detention pond has been calculated to be 0.64 acre-feet using the FAA method. The pond size was computed for drainage from Basins 1, 2 ' and 4 only. Basin 3, Boardwalk Drive, is not included in these calculations because it is allowed to run off undetained per the Master Drainage Plan. Basins 5 and 6 are not included in the calculation because they drain into Boardwalk Drive and also run off undetained. The Master Planned 2 year release rate for Basin 202 was 0.12 cfs/acre. In order to help compensate for the undetained release of Basins 5 & 6 during events less than or equal to the 10 year event, the proposed 2 year release rate ' for this site has been reduced to 0.09 cfs/acre. The Master Planned 100 year release rate for Basin 202 is 0.50 cfs/acre which translates into an allowable release for this site (Basins 1, 2, 4, 5 and 6, 4.02 acres) of 2.01 cfs. The detention pond has been designed to release at 1.80 cfs in order to partially compensate for the undetained run off from Basins 5 & 6 (2.6 cfs). This rate will be controlled by an orifice plate structure attached to the upstream end of the 15" HDPE outfall pipe. As can be seen from the SWMM output located in the appendix, the required storage in the downstream detention pond #180 (2.8 acre-ft) does not change when the area of site Basins 5 & 6 is added to SWMM Basin #214 (Boardwalk Drive), nor does the total flow under Lemay Avenue exceed the allowable flow of 120 cfs. The net 100 year flow increase in the release from this site (2.39 cfs) is obtained by taking the allowable release (2.01 efs) less the pond release (I.80 cfs) and subtracting this difference from the release from Basins 5 & 6 (2.6 cfs). A variance for the release of 2.39 cfs is being sought from the Stormwater Utility for the undetained release Iduring the 100 year storm event. The detention pond has been designed to realize a 100-year water surface elevation of 4999.29, providing 1.01 feet of freeboard. An emergency overflow spillway has been designed that will allow stormwater to flow into Boardwalk Drive should the ' outlet become plugged. 4 •[fliis • unofficial copy was downloaded on Scp-10-2012 from the City of Fort Collins Public Records Websitc: http://citydocs.fbgov.eom or additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA F, 60A 4 IV. STORM WATER QUALITY ' A. Gener_al Concept The water quality of storm water runoff must be addressed on all final design utility plans. Construction is anticipated to begin in the Fall of 1997. We have sought to find various Best Management Practices for the treatment of stone water runoff. The on -site grass -lined detention pond provides some filtration and time for impurities to settle out of the stormwater runoff. VI. EROSION CON RO A. General Concept The Miramont office Park lies within the Moderate Rainfall and Wind Erodibiiity Zone per the City of Fort Collins zone maps. The potential exists for silt movement ' during construction of the parking/driveways and building. Thus the new improvements will be subjected to both wind and rainfall erosion. te Per the Crtv of Fort Col__ i Erosion Contlo� RPfP*Pn�p Manual for Con liithe aendixtithei iesro7s5io3n acnonatroelr pceorformance -shoanction standP 6. From the calculations in the appendix, the effectiveness (EFF) of the is 88. proposed erosion .control plan is 81.07 during construction and 98.29 after construction. It is anticipated that the construction duration of this project will be less than 8 weeks due to the limited amount of work to be completed, therefore the erosion control plan as specifically detailed below, should meet the City of Fort Collins requirements. A copy of the erosion control calculations is included in the Appendix. An erosion control escrow cost estimate of $13,755 is also included in the Erosion Control Section of the Appendix. IB. �ismme )Details Before the start of over lot grading the silt fencing shown on the drainage and erosion control plan should be installed. ' In order to protect the curb chases from receiving excessive silt deposits, the curb chases will have gravel filters installed around them. A sediment -trap will be provided in the detention pond until the pond is vegetated. The above items can be removed once asphalt and landscaping in their respective areas have been completed. 5 is unofficial copy was downloaded on Scp-10-2012 from the City of Fort Collins Public Records Streeter Forhttt Cki ns, Co90524 US ........At infnnnntion or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, C80524 US VII. CONC► USIONS A. COmnliance with Standards All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria. ' B. Damage onceot The proposed drainage concepts presented in this report and shown on the Drainage ' and Erosion Control Plan are in compliance with the City of Fort Collins drainage criteria This project was designed to be in conformance with the intent of the McClelland's Basin Master Drainage Plan. C. Storm water Oaality Because storm water quality has become a requirement, the site has addressed this storm water aspect. We have designed the erosion control to reduce the sediment which runs into the storm water system. The on -site detention pond also provides a settling period during which impurities may be filtered out of the stormwater runoff before leaving the site. .' D Frnainn ['Ontrol COOCCDt The proposed erosion control plan adequately provides for the control of wind and rainfall erosion from the study site. The proposed erosion control concepts presented in this report and shown on the Erosion Control Plan are in compliance with the City of Fort Collins erosion control criteria. N. '.I ' is unofficial copy was downloaded on Scp•10-2012 from the City of Fort Collins Public Records Street Fort Collins,i CO80524 US __ .aa:.;....I infnrrnadon or an official copy, please con�act City of Fort Collies Utilities 900 Wood Street roil Colns, C80524 US I I�I F 11 t [1 i i 1 1 F 1 j r 1. City of Fort Collins, Drain Qe Dr�ir1, Criteria snd ConMruction Standards. May 1984, Revised 1992. F Control RPfertlic.zMmm for c�n=ic- m Sites January 1992. 2. City of Fort Collins, � sSL39' .g. 3. Overall Drainage Study for Oak/Cottonwood Farm, MCClellands Basin, Fort Collins, Colorado, by RBD, Inc., May 4, 1992, revised October 10,1994. 4. McClellands Basin too -year Master Plan Update (County Road 9 to Fairway Estates) for Proposed Modifications to the Oakridge Village Regional Detention Pond, Fort Collins, Colorado, by RBD, Inc., April 1,1996 Inis mofficiel copy a ss downloaded on Sep-IO _2012 from. r amity Fart rnIIlns Util ities ties 700 Wood Street Fort Collins, Co 80524 USA I STANDARD EROSION CONTROL CONSTRUCTION PLAN NOTES 1.1. all a 1-1 a0m. a—." F..W r d 4. N0«.I IN1114 M F.. P'I. 1. NJ .NMrvaVN - Y.N d. y . H I.y YM yaM.lY dl 1.4F. Aid N F.U« 1. mJ M pNM1X MMI .a1n. V w tt, at 1. alai N eyF r ra aM w W •nwnl IMI Feld« WF.i+ � � 1wNu F <a.buelln «y«e..l WN1M F PI ypPM pNjil tM. tti rna wW rraM1 NNI. d pNYy 4U Y inYly 4NVNpMn b JXa ,. . M :NY4,II�w.y �ilMNlrs a I Ww i «w .w :p,Y« w N.nilal p. wiwaom yr.IM+ M 4- W M1«I 1wIW i.I« 01M. 1 N Nb y W ..Y. Mn. p..u.. MW1� (lugNr��.F�NpF� way wtI�} .Wp11y () NF` W. M « amitlN . 1� �ONIpM NN Y e�iw «,1 mMC}TG ..4.l.Rn s .0 yA.muMl .MN wuai a �Ju1 N„ 1 b'mphM II�+gWry p> ii qiM; �rWn<m'Y/ ;«4'•i.0 �IW.ryFj lo.J N MIdN WN. W YM eEX.r.i b N. fN-M. VIL"911. 1 1 r M p.Nrly IFd b N1rN w I.i pIWu1d y,d..IN11 .p•w ,W MMIW Y N N pawl iq.i-a.wM r.Mw H 4 MMtl4d MnrMN .N WN..MM°X.y14101. I..ih4M pT.M..a 6Nrsl1« !i N. 411 « %.X 1Nm11u<NYu N I.rny.rJ ,Nvyr� .nlm wW me..11 4d M Nwll« M rinl« v V' FMMd HSIM N n1aFM MI.w1 MMJsry MA w N�yf .N.N .a1N- d sM rI.OM rN OIy..N 01 N . rnW V nl Naatl« N M MI N «YIN IM. Nyl. NN J e.aN..y M M .IMFk M .XW In I^ bN X WIWE AN ~ IN M N p.IMM mot rN1 N1r b h.Y4 NY M XM .bM VNN.111 ..IN. N4 N J.Ya.lr . l aF1y O.p M N NNY .M nllMna{M1� .I 01, O. paM. OwM i 4.e q,t,, n wmet r nl MM IM.10 mN •I y Wmot iM11. F 1 1.r1. «« M 4wN S 0 / SEDIMENT TRAP CONSTRUCTION NOTES 1. 1 INSTALL NETENTIO1` as dUOdCICY a o°�vEa�w14E" brvou"cro�E,WmRNOiP�'"aN�° Iw7pnpipOPMmpcE 4. A° ONPUUU =0 NBIC Y�3 IX YOLW ME/ a $1111OF M'O1TBASH ESION OEP°WiF W GEM e. REWOMA IrAWIT 94V SC BE 77 M M AREA R4BVTART 10 A DIYEnr BAFN. B �r�. • • •�©• . •gyp etJ•�ES=13L1C_ffS7�7�S lAll Ell.11L)l♦lTJF70®E3 �f:S� O�fu��F1F�it3)•�G Erb i112 � F, � fFP[`iei il�si�ei ��!��.IOaEIi' Il tlf[fIC1 REIN EROSION CONTROL CONSTRUCTION SEQUENCE NIO 1i Y01M 111YIi 1YIJ I i 1 AI l IO M1140i gippp 1140 Uen4 GW IMLL id«n.w viNNM.M. lrrb. MI 1w�wIN'uw °1°N 0°'°I0. tAgNA°w I..Y.M tNRN. IW. 4vrin WI iwN..�lsAw I�gb1Np�M4iMni 1/Cpe.l. M.M 01An .-OeA uaW KG IA q A..wnl fM FINnl1 .M �. �er'1v}).1NMi nFAh1 N.11Fy./M.1./BnNy OM. 4+rt PNMrI[4—i+rllo� n or Ir rar ICWYt a LEGEND 1 �4%09_ fMtMO CONTOUR I --P SNALE/b1T[N ./ ROW ARRON —04� PROPOSED CONTOUR II STRAW BALE OIECK DAY ---e004, -BNOr ONE- PROPOSED CONTOUR R SILT FOXE DISSECTION OF FLOW ) - 1E'"Si VASYM STORM PPE QDESIGN POINT ��- PROPOSED OTORW PIPE 0111-411A ORAMAd: BASM BOUNDARY too w WSEL e SAWN NWSER WEFT FILTER AREA -�®—J -- SEONENT TRAP AIL- AVERACE STREET RAPE 1 SCAB I+ • 1 0 X 0- N 14 E N 14 PROMO[ CON1P0.� ADNTS O TOP MIENYALS CONCRETE TRICKLE PAN 1 • FRONT RANEiE D Dnvrfsr MDTCN I "On1ro. lTLv T \_i r� It DAM ONE AT T 1;a i HARMONY MARKET F 111-14 TO BANE ONE CONTOURS Ar-PROPOM IME STAGED RETDASM ESTRUQAIPO LXtT1At EMERGENCY OVERFLOW N..FWI.Xv.M...p..4.1: TR An MrlpgfrafgNNll.rw..`MNpLarOp--. ntli6.I Jrn.ianru.I1W r114 TN4 rwM1in(rIXlI1L OALI. IITe1TY FgTl 111M CPNIIBI Of COEORADO 1-e00-922-1987 a 534-6700 w . I INIM MY of Pert CoDins, Calwad, CNCOEEO Br CHECKED BrAIA 'a"' a A.+ CHECKED or. CHECKED O/ECKED or. 0 0 604-021 eX+«Ao An 3of8 i E r I MO ' k ' Y j �A. a • 4P k •; ♦it r it xl 7• i � a. Muamont Pond ` • Retrofit Existing Pond to accommodate Water Quality Volume go Ridge EpAd • Retrofit Existing Pond to accommodate', Water Quality Volume McClellands Creek Basin Proposed BMP Basin Type Flood Control Only Water Quality Only Flood Control and Water Quality &Lw Proposed Improvements -- Proposed Selected Plan Water Quality Alternatives C3 Natural Area A,-- Proposed Stream Restoration and Habitat Improvements C (Q)T Fort Collins EMOFIEERIIIG, IrIC Sty WIIJ.w Sgrinos Pond m • Retrofit Existing Pond to accommodate Water Quality Volume to�IIIIIIII N. s( s WORK y/ I I fT �. a , I ' t Harmony Crossing Pond ! ..r,•. • Retrofit Existing Pond to accommodate Wet., Quality Volume - W- � � teiea i • -. .. _ _ I N Preston Jr. High Pond ♦ • Retrofit Existing Pond to accommodate - Water Quality Volume Ptopoaed Stream Restoratlon ' :aM Hahhet lmprovanMb KECHTER RD- ' �a.t7 i � l7":K-4Gr;,L.w .; :j ' gas:! i t%• tra 4 McClellands Creek Basin Selected Plan - Water Quality Improvements P L- N 0 660 L729 - 1,990 1,640 N P Feet 7 loch a 0.125 mills 5 l - (CLAN (� �� r Final Drainage Report for The Learning Experience at Miramont Office Park 17 FENOVEEX SYOEWAU( TY9c r iu cr gFim s011 11111 wisim 1111111 FOIN FRIF 11110 MINE =00 FINE viiiii 10110 B2 iiis Film Film mills iiiiiii � SOARDWALKDRIVE 0.78 FX OVHlfIpY1N:F AREA DRAINlass _ _ O.B2 _..__ _ s _ saw Films:_�_ 6UNDERDRAIN AREAgrAIN � - S1 4725•W 281.55 _ � -- =1:E� - r ' V - _ ___ _.w2 sooz -. 500. _ - �► sDD 4,524 SF s0oo=- ' /�. *Po'ze I A4 49w- 4ws- 1 _� II Y RCR SD 013 0.3 A 83 ! nI LOT 1 I�I�I MIRAMONTOFFICER DRAINAGE LEGEND ------S2B1----- EMSPNGMINORCONTOUR -----i5 B ----- EKISTINGMNORCONTWR 5281- PROPOSEDMINOR CONTOUR �280 � PROPOSED MNOR CONTOUR �7!5PROPOSED STORM SEWER LINE PROPDSEDMANHOLE PROPOSEDSO%BASEMANHOLE on PROPOSED INLET 0 PROPOSED FLARED END SECTION • • • • EK. BASIN BOUNDARY PER ORIGINAL REPORT • Am Am sm m m n MINOR BASIN BOUNDARY M M M MAOR BASIN BOUNDARY TC ROW PATH A7 BASINID 0. W 5 YEAR RUNOFF COEFFECIENi 0, tODYFAR RUNOFFCOEFFlGFM Hq$INAFFA (ACRE$) QPROPOSED OE$IGN POIM ROW ARRgV OVERFLOW PATH y DRAINAGE ARROWS LOT2 MIRAMONT OFFIC PART II I A7 2R 0.79 O.B4 n 2-WROOF THE LEARNING EXPERIENCE A6 RCELE EY 2ME4Y2ALF AS 2 WROOF QUK L/ ORANS \ T L1 STM 1AINLE INN..OUT ((Ir =4BMAl (S) IIFFF 11111m Kills Kills III BD.95 FFE =05009 60 D.11 t = { D -PAON WATER Tt 0 N I Iry T> RIPS El �-y! �9 .EXK4)7AGLiPA4NaGE ' `I$ . W PROPOSED ORNNAGE, I ACCESSMg \ y £ ACCESSNID UTILRY EBMT I � Ul&/ryESMr \ X, I \ I vAwAmv2DrLOTS `� MIRAMON OFFICE PARK U U B1 DES 0 D.9O � n i n, FRONT RANGE BAPTIST CHURCH VRETANIW�L OCK LVARIESCE BLOCK FROM040' TO 4.95'PE VARIES HIGH IES IMTH WALL HE16HT AND BATTER TYPICAL DETAIL LANDSCAPE WALL NOT TO SCALE SUMMARY RUNOFF TABLE Basin Des nP4Nnl AIN AC C2 CS 1 DIN 1 1% p 2 ear p Ila Yu Al Al 2.26 0.79 079 094 1 73.2% 3.85 1135 A2 A2 0.65 0.0 0.85 0.90E72.6% 1.52 5A2 A3 A3 0.21 0.28 0.28 0.34 0.17 0/1 A4 A4 0.13 0.33 0.33 0.39 0.11 0.45 AS AS 0.11 0.95 DO 1.00 0.29 1107 AS AS 0.11 0,95 0.95 1.00 0.29 1 7 A7 A7 0.18 0.67 0.67 0.73 0.32 119 B1 B1 038 0.76 0.76 0.62 OS1 B2 B2 076 01 0.77 0.82 USB3 B3 095 0.69 0.69 0.74 0.11 RASIN A= 3.65 AC ROW FROM CHURCH PROPERTY-1 WCFS STM MH 1 1.4-DM MH RIM-4 .73 1 INV IN(12')-498&i0(N) F INV 021-4 70(8), 1TRCP 80 _ - /rLGppAAPPIM,1QEAYO 1TF£s T DRI UA2IN�ESMr INVM9BBA0 ipp M Y L T2 MIRAM SELF STORAGE I i l I BASIS OF BEARINGS THE NORTH LINE OF THE NORTHEAST QUARTER OF NOTE: SECTION 1 TOWNSHIP 6 NORTH, RANGE 69 WEST OF THE 1. FOR REVEGETATION DETAILS, SEE LANDSCAPE PLANS. SIXTH PRINCIPAL MERIDIAN IS CONSIDERED TO BEA6R NORTH 89.58'54" EAST. BENCHMARK NGS CONTROL POINT Y402 BEING A STAINLESS STEEL ROD IN A RANGE BOX ON EAST SIDE OF HIGHWAY 207, 900t SOUTH OR HARMONY ROAD. PUBLISHED ELEVATION 5018.96 (NAVD88) DEMPITION/WATER QUALITY POND WQCV REQUIRED = 0.09E AG FT WQCV PROVIDED G149AC-R 10-YR VOLUME REQUIRED 0.330AC-R+WQCV4.428AC-FT 10-YR VOLUME RPROVIDED OA35 M-FT 100YR VOLUME REQUIRED O.621AC-FT+WQCVWJI9AOFT IODYR VOLUME PROVIDED 0.750 AC -FT WQCV WATER SURFACE ELEVATION 4999.00 10" WATER SURFACE ELEVATION 5000.90 IODYR WATER SURFACE ELEVATION 5002.59 OVERFLOW WEIR WATER SURFACE ELEV. 5002.59 10YB ALLOWABLFRETME RATE - BASINA 0.2 CFSAC=073 CF5 ]N6YR ALLOWABLE RELEASE RATE - BASINA IO5CFSW=2JI3 CF5 CITY OF FORT COLLINS, COLORAOO UTILITY PLAN APPROVAL APPNWEP. CITY ENGINEER pin - CHECKED BY'. WATER AWASTEWATER UTILITY DATE CHECKED 9Y: STORMWATER UTNTY DATE CHECKED BY: PARKS B RECREATION TE CHECKED BY: TRAFFIC ENGINEER TE CHECKED BY. _ ENVIRONMENTALPUNNER PATE CHECKEDBY. TE W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0 El �-y! �9 .EXK4)7AGLiPA4NaGE ' `I$ . W PROPOSED ORNNAGE, I ACCESSMg \ y £ ACCESSNID UTILRY EBMT I � Ul&/ryESMr \ X, I \ I vAwAmv2DrLOTS `� MIRAMON OFFICE PARK U U B1 DES 0 D.9O � n i n, FRONT RANGE BAPTIST CHURCH VRETANIW�L OCK LVARIESCE BLOCK FROM040' TO 4.95'PE VARIES HIGH IES IMTH WALL HE16HT AND BATTER TYPICAL DETAIL LANDSCAPE WALL NOT TO SCALE SUMMARY RUNOFF TABLE Basin Des nP4Nnl AIN AC C2 CS 1 DIN 1 1% p 2 ear p Ila Yu Al Al 2.26 0.79 079 094 1 73.2% 3.85 1135 A2 A2 0.65 0.0 0.85 0.90E72.6% 1.52 5A2 A3 A3 0.21 0.28 0.28 0.34 0.17 0/1 A4 A4 0.13 0.33 0.33 0.39 0.11 0.45 AS AS 0.11 0.95 DO 1.00 0.29 1107 AS AS 0.11 0,95 0.95 1.00 0.29 1 7 A7 A7 0.18 0.67 0.67 0.73 0.32 119 B1 B1 038 0.76 0.76 0.62 OS1 B2 B2 076 01 0.77 0.82 USB3 B3 095 0.69 0.69 0.74 0.11 RASIN A= 3.65 AC ROW FROM CHURCH PROPERTY-1 WCFS STM MH 1 1.4-DM MH RIM-4 .73 1 INV IN(12')-498&i0(N) F INV 021-4 70(8), 1TRCP 80 _ - /rLGppAAPPIM,1QEAYO 1TF£s T DRI UA2IN�ESMr INVM9BBA0 ipp M Y L T2 MIRAM SELF STORAGE I i l I BASIS OF BEARINGS THE NORTH LINE OF THE NORTHEAST QUARTER OF NOTE: SECTION 1 TOWNSHIP 6 NORTH, RANGE 69 WEST OF THE 1. FOR REVEGETATION DETAILS, SEE LANDSCAPE PLANS. SIXTH PRINCIPAL MERIDIAN IS CONSIDERED TO BEA6R NORTH 89.58'54" EAST. BENCHMARK NGS CONTROL POINT Y402 BEING A STAINLESS STEEL ROD IN A RANGE BOX ON EAST SIDE OF HIGHWAY 207, 900t SOUTH OR HARMONY ROAD. PUBLISHED ELEVATION 5018.96 (NAVD88) DEMPITION/WATER QUALITY POND WQCV REQUIRED = 0.09E AG FT WQCV PROVIDED G149AC-R 10-YR VOLUME REQUIRED 0.330AC-R+WQCV4.428AC-FT 10-YR VOLUME RPROVIDED OA35 M-FT 100YR VOLUME REQUIRED O.621AC-FT+WQCVWJI9AOFT IODYR VOLUME PROVIDED 0.750 AC -FT WQCV WATER SURFACE ELEVATION 4999.00 10" WATER SURFACE ELEVATION 5000.90 IODYR WATER SURFACE ELEVATION 5002.59 OVERFLOW WEIR WATER SURFACE ELEV. 5002.59 10YB ALLOWABLFRETME RATE - BASINA 0.2 CFSAC=073 CF5 ]N6YR ALLOWABLE RELEASE RATE - BASINA IO5CFSW=2JI3 CF5 CITY OF FORT COLLINS, COLORAOO UTILITY PLAN APPROVAL APPNWEP. CITY ENGINEER pin - CHECKED BY'. WATER AWASTEWATER UTILITY DATE CHECKED 9Y: STORMWATER UTNTY DATE CHECKED BY: PARKS B RECREATION TE CHECKED BY: TRAFFIC ENGINEER TE CHECKED BY. _ ENVIRONMENTALPUNNER PATE CHECKEDBY. TE W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0 SUMMARY RUNOFF TABLE Basin Des nP4Nnl AIN AC C2 CS 1 DIN 1 1% p 2 ear p Ila Yu Al Al 2.26 0.79 079 094 1 73.2% 3.85 1135 A2 A2 0.65 0.0 0.85 0.90E72.6% 1.52 5A2 A3 A3 0.21 0.28 0.28 0.34 0.17 0/1 A4 A4 0.13 0.33 0.33 0.39 0.11 0.45 AS AS 0.11 0.95 DO 1.00 0.29 1107 AS AS 0.11 0,95 0.95 1.00 0.29 1 7 A7 A7 0.18 0.67 0.67 0.73 0.32 119 B1 B1 038 0.76 0.76 0.62 OS1 B2 B2 076 01 0.77 0.82 USB3 B3 095 0.69 0.69 0.74 0.11 RASIN A= 3.65 AC ROW FROM CHURCH PROPERTY-1 WCFS STM MH 1 1.4-DM MH RIM-4 .73 1 INV IN(12')-498&i0(N) F INV 021-4 70(8), 1TRCP 80 _ - /rLGppAAPPIM,1QEAYO 1TF£s T DRI UA2IN�ESMr INVM9BBA0 ipp M Y L T2 MIRAM SELF STORAGE I i l I BASIS OF BEARINGS THE NORTH LINE OF THE NORTHEAST QUARTER OF NOTE: SECTION 1 TOWNSHIP 6 NORTH, RANGE 69 WEST OF THE 1. FOR REVEGETATION DETAILS, SEE LANDSCAPE PLANS. SIXTH PRINCIPAL MERIDIAN IS CONSIDERED TO BEA6R NORTH 89.58'54" EAST. BENCHMARK NGS CONTROL POINT Y402 BEING A STAINLESS STEEL ROD IN A RANGE BOX ON EAST SIDE OF HIGHWAY 207, 900t SOUTH OR HARMONY ROAD. PUBLISHED ELEVATION 5018.96 (NAVD88) DEMPITION/WATER QUALITY POND WQCV REQUIRED = 0.09E AG FT WQCV PROVIDED G149AC-R 10-YR VOLUME REQUIRED 0.330AC-R+WQCV4.428AC-FT 10-YR VOLUME RPROVIDED OA35 M-FT 100YR VOLUME REQUIRED O.621AC-FT+WQCVWJI9AOFT IODYR VOLUME PROVIDED 0.750 AC -FT WQCV WATER SURFACE ELEVATION 4999.00 10" WATER SURFACE ELEVATION 5000.90 IODYR WATER SURFACE ELEVATION 5002.59 OVERFLOW WEIR WATER SURFACE ELEV. 5002.59 10YB ALLOWABLFRETME RATE - BASINA 0.2 CFSAC=073 CF5 ]N6YR ALLOWABLE RELEASE RATE - BASINA IO5CFSW=2JI3 CF5 CITY OF FORT COLLINS, COLORAOO UTILITY PLAN APPROVAL APPNWEP. CITY ENGINEER pin - CHECKED BY'. WATER AWASTEWATER UTILITY DATE CHECKED 9Y: STORMWATER UTNTY DATE CHECKED BY: PARKS B RECREATION TE CHECKED BY: TRAFFIC ENGINEER TE CHECKED BY. _ ENVIRONMENTALPUNNER PATE CHECKEDBY. TE W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0 RASIN A= 3.65 AC ROW FROM CHURCH PROPERTY-1 WCFS STM MH 1 1.4-DM MH RIM-4 .73 1 INV IN(12')-498&i0(N) F INV 021-4 70(8), 1TRCP 80 _ - /rLGppAAPPIM,1QEAYO 1TF£s T DRI UA2IN�ESMr INVM9BBA0 ipp M Y L T2 MIRAM SELF STORAGE I i l I BASIS OF BEARINGS THE NORTH LINE OF THE NORTHEAST QUARTER OF NOTE: SECTION 1 TOWNSHIP 6 NORTH, RANGE 69 WEST OF THE 1. FOR REVEGETATION DETAILS, SEE LANDSCAPE PLANS. SIXTH PRINCIPAL MERIDIAN IS CONSIDERED TO BEA6R NORTH 89.58'54" EAST. BENCHMARK NGS CONTROL POINT Y402 BEING A STAINLESS STEEL ROD IN A RANGE BOX ON EAST SIDE OF HIGHWAY 207, 900t SOUTH OR HARMONY ROAD. PUBLISHED ELEVATION 5018.96 (NAVD88) DEMPITION/WATER QUALITY POND WQCV REQUIRED = 0.09E AG FT WQCV PROVIDED G149AC-R 10-YR VOLUME REQUIRED 0.330AC-R+WQCV4.428AC-FT 10-YR VOLUME RPROVIDED OA35 M-FT 100YR VOLUME REQUIRED O.621AC-FT+WQCVWJI9AOFT IODYR VOLUME PROVIDED 0.750 AC -FT WQCV WATER SURFACE ELEVATION 4999.00 10" WATER SURFACE ELEVATION 5000.90 IODYR WATER SURFACE ELEVATION 5002.59 OVERFLOW WEIR WATER SURFACE ELEV. 5002.59 10YB ALLOWABLFRETME RATE - BASINA 0.2 CFSAC=073 CF5 ]N6YR ALLOWABLE RELEASE RATE - BASINA IO5CFSW=2JI3 CF5 CITY OF FORT COLLINS, COLORAOO UTILITY PLAN APPROVAL APPNWEP. CITY ENGINEER pin - CHECKED BY'. WATER AWASTEWATER UTILITY DATE CHECKED 9Y: STORMWATER UTNTY DATE CHECKED BY: PARKS B RECREATION TE CHECKED BY: TRAFFIC ENGINEER TE CHECKED BY. _ ENVIRONMENTALPUNNER PATE CHECKEDBY. TE W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0 BASIS OF BEARINGS THE NORTH LINE OF THE NORTHEAST QUARTER OF NOTE: SECTION 1 TOWNSHIP 6 NORTH, RANGE 69 WEST OF THE 1. FOR REVEGETATION DETAILS, SEE LANDSCAPE PLANS. SIXTH PRINCIPAL MERIDIAN IS CONSIDERED TO BEA6R NORTH 89.58'54" EAST. BENCHMARK NGS CONTROL POINT Y402 BEING A STAINLESS STEEL ROD IN A RANGE BOX ON EAST SIDE OF HIGHWAY 207, 900t SOUTH OR HARMONY ROAD. PUBLISHED ELEVATION 5018.96 (NAVD88) DEMPITION/WATER QUALITY POND WQCV REQUIRED = 0.09E AG FT WQCV PROVIDED G149AC-R 10-YR VOLUME REQUIRED 0.330AC-R+WQCV4.428AC-FT 10-YR VOLUME RPROVIDED OA35 M-FT 100YR VOLUME REQUIRED O.621AC-FT+WQCVWJI9AOFT IODYR VOLUME PROVIDED 0.750 AC -FT WQCV WATER SURFACE ELEVATION 4999.00 10" WATER SURFACE ELEVATION 5000.90 IODYR WATER SURFACE ELEVATION 5002.59 OVERFLOW WEIR WATER SURFACE ELEV. 5002.59 10YB ALLOWABLFRETME RATE - BASINA 0.2 CFSAC=073 CF5 ]N6YR ALLOWABLE RELEASE RATE - BASINA IO5CFSW=2JI3 CF5 CITY OF FORT COLLINS, COLORAOO UTILITY PLAN APPROVAL APPNWEP. CITY ENGINEER pin - CHECKED BY'. WATER AWASTEWATER UTILITY DATE CHECKED 9Y: STORMWATER UTNTY DATE CHECKED BY: PARKS B RECREATION TE CHECKED BY: TRAFFIC ENGINEER TE CHECKED BY. _ ENVIRONMENTALPUNNER PATE CHECKEDBY. TE W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0 CITY OF FORT COLLINS, COLORAOO UTILITY PLAN APPROVAL APPNWEP. CITY ENGINEER pin - CHECKED BY'. WATER AWASTEWATER UTILITY DATE CHECKED 9Y: STORMWATER UTNTY DATE CHECKED BY: PARKS B RECREATION TE CHECKED BY: TRAFFIC ENGINEER TE CHECKED BY. _ ENVIRONMENTALPUNNER PATE CHECKEDBY. TE W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0 W Y U 0: Z Q W 0. Rw wU 0_ LL w LL I� Z Z 20 0: 2 w�_ w� F Q 9 13 ,ad v Z U2.0