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HomeMy WebLinkAboutSite Certifications - 10/09/2014WEST RANGE FORT COLLINS J�Ivs.d/CSfrow �fw CD `°tyof r� FOB COn S 406 West Laurel Street � vov•C".� Joy-J�0.��ct -9-4 l'3O� S2�{- w CLIP �•t . COMMERCIAL, MULTI -FAMILY AND SUBDIVISION CERTIFICATION CHECKLIST (Overall Site Drainage) Please fill in all applicable items in this Certification Form for Commercial, Multi -Family and Overall Single Family sites. A copy of the approved grading plan must be submitted with the as - built grading plan. (It is preferred to have the as -built elevations written in red next to the approved elevations) Use "OK" for items checked or actual numbers for items verified/surveyed in the field. Use "N/A" for items that are not applicable to the site that is being certified. Please provide an As -Built Redlined or Mylar drawing showing the following: A. Detention, Drainage Facilities, and Common Open Spaces 1. Pond Certification OK • Provide Topographic Records and Volume Verification Calculations * • Provide Pond Cross -Sections and Spot Elevations (especially @ Pond Embankment and Pond Flow Line) N/A • Positive Fall to Pan (if applicable) ,� • General Pond Grading including all Side -Slopes * • Invert Elevation OK • Forebay Construction and Elevation OK • Spillway Weir (Location, Elevation, Height, Opening Width) OK • Placement and size of riprap or alternative permanent erosion control measures *OK • Orifice Plate and/or Water Quality Outlet Structure Installation *OK • Water Quality Capture Volume (Volume Required, Volume Provided and Water Surface Elevation) N/A • Berm and Embankment Compaction Level OK • Subsurface Media for Water Quality Ponds and Swales SINGLE ASTERISK (*) = REFER TO RECORD DRAWINGS AND/OR SUPPLEMENTAL MEMO. ■� (NORTHERN ENGINEERING City of For! Collins 2. Swales N/A • Location (are they within easement?) N/A • Dimension and Cross -Section Verification N/A • Longitudinal Slopes and Side -Slopes N/A • Spot Elevations N/A • Permanent Erosion Control Measures (drop structures, riprap, lining) N/A • Tie-in to Storm Lines, Pans, Curbs, or other appurtenances N/A • Required Minimum Freeboard, Provided Freeboard N/A • Landscaping Infringement on Flow Line? 3. Pipes OK • Size and Type OK • Slopes (As -Built and comparison to 0.4% Minimum) N/A • Pipe Capacity Calculations (if slopes are significantly altered from design) OK • Invert Elevations *N/A • Installation and Backfill OK • Cover *N/A • Encasement and Clearance from other nearby utility lines *N/A • Joints Type and construction SINGLE ASTERISK (*) INDICATES ITEMS NOT ABLE TO BE VERIFIED BY ENGINEER. NORTHERN 2 WEST RANGE FORT COLLINS ENGINEERING 406 West Laurel Street Cit,.y}of Collins 4. Concrete Pan Channels OK • Size OK • Slope OK • Cross Section *N/A • Thickness OK • Elevations S. Inlets N/A . Size and Type N/A • Size of Opening (or name of Standard Detail used) N/A • Grate Elevation N/A • Invert Elevation N/A • Box Size 6. Street Cross -Pans N/A . Size N/A • Type N/A. Grade N/A • Elevations N/A • Cross -Sectional Depth N/A • Tie-in to Curb and Gutter SINGLE ASTERISK (*) INDICATES ITEMS NOT ABLE TO SE VERIFIED BY ENGINEER. .V NORTHERN 3 WEST RANGE FORT COLLINS E N G I N E E R I N G 406 West Laurel Street Collins "I City of 7. Culverts N/A • Size N/A • Type N/A • Invert Elevations N/A • Headwalls or Wing Walls 8. Sub -Drains *OK . Size *OK • Type (Perforated/Solid) *OK • Cover *OK • Backfill *OK • Geo-Textile Liners *OK • Clean -Outs 9. Curb Cuts OK • Size OK • Tie-in to Swale, Pipe or other appurtenances 10. Common Open Spaces N/A • Overall grading contours of open spaces N/A • Spot elevations adjacent to private lots (property corners) SINGLE ASTERISK (-) = REFER TO RECORD DRAWINGS AND/OR SUPPLEMENTAL MEMO NORTHERN 4 WEST RANGE FORT COLLINS ENGINEERING 406 West Laurel Street B. Grading certification 1. Certification of Grade Elevations: OK • Minimum Opening Elevations OK • Top of Foundation Elevations OK • Comparison to 100-year Water Service Elevations OK • Comparison to Freeboard Elevations and Base Floodplain Elevations — BFE 2. Verification of Site Grading: *OK • Engineer to evaluate site grading compliance with the approved grading plan. *OK • As -built elevations are to be redlined onto the approved grading plan sheet showing the as -built spot elevations next to the design spot elevations so compliance can be verified and documented. C. Certification of Erosion Control Measures: 1. Permanent BMP Measures: OK • Permanent Vegetation (no more than 6" bare spots and weeds under control) OK • Riprap or alternative permanent erosion material OK* Riprap Bedding N/A• Cut -Off Walls or Channel Drop Structures Cross -Sections OK • Sediment Basins OK • Water quality ponds/Sand Filter/Bio Retention Construction and liners N/A• Permanent Netting Mats or Blankets OK • Mulching and Seeding SINGLE ASTERISK (-) = REFER TO RECORD DRAWINGS AND/OR SUPPLEMENTAL MEMO. ■� NORTHERN 5 WEST RANGE FORT COLLINS ENGINEERING 406 West Laurel Street of •�tf 2. Temporary BMP Measures: N/A • Mulching and Seeding N/A • Temporary BMP Measures as shown on Erosion Control Plan D. Post -Construction Site Cleanup: OK • Construction Debris Clean -Up (In particular debris affecting the drainage) OK • Smoothing of Ruts in all Construction Areas OK . Reseeding of all Areas Affected by Construction Activities (Usually enforced by the City's Erosion Control Inspector but the engineer Certifying the site needs to notify the contractor if areas are not seeded) E. Statement of Compliance: This certification is signed and stamped and by signing this form the Engineer(s) attests that they have inspected the site and to the best of their knowledge the as -built conditions of the drainage facilities are as described in the above form and in the As - Built plans enclosed. Failure to properly disclose all known information could result in the rejection of this certification and prevent the release of any and all Stormwater Utility permit holds on Building Permits and/or Certificates of Occupancy within this development. PLEASE REFER TO RECORD DRAWINGS AND SUPPLEMENTAL MEMO FOR ADDITIONAL INFORMATION. F. Signature and Stamp by a Colorado Registered Professional Engineer t�EypDO L/C AN o .• wii( 'i •' 09.18.24� Nicholas W. Haws, PE, LEED AP Colorado PE Registration No. 39767 NORTHERN 6 WEST RANGE FORT COLLINS E N G I N E E R I N G 406 West Laurel Street W I NORTHERN ENGINEERING Supplemental Memorandum to Overall Site Drainage Certification Date: September 18, 2014 Project: West Range Fort Collins 406 West Laurel Street Fort Collins, Colorado 80521 Permit No. B1304524 Attn: Mr. Dan Mogen, El City of Fort Collins — Stormwater Utility 700 Wood Street Fort Collins, Colorado 80521 Dear Dan. NE Project No. 875-001 This memorandum serves to supplement standard checklist items outlined on the Commercial, Multi -Family and Subdivision Certification Checklist, as published on the City of Fort Collins' website. Specifically, it is intended to offer additional explanation and information relative to the bioretention pond and overall stormwater management volumes. This site was a challenge from the onset with respect to physical constraints concerning a shallow outfall, Arthur Ditch, etc. The general design approach agreed to during the development review process was to bring the site up to modern standards to the greatest extent feasible, and to not make the drainage condition any worse than that which existed prior to the West Range Fort Collins development. While the spirit of the approved design concepts and intentions has been fulfilled, there are certain construction details and volumes that have varied. A discrepancy was encountered during construction with respect to the pond outfall pipe elevation and the bottom of the footings for the pond walls. In order to ensure a full bioretention section was maintained, the pond bottom had to be raised slightly, which in turn required the roof drain pipe and outlet control to be modified. Rather than discharging onto the surface of the pond, the roof drain pipe now has a subsurface release into the #4 aggregate layer. A cleanout riser is provided at the discharge point for observation and maintenance. Significant opportunities exist for filtering, adsorption, biological update, and infiltration prior to roof water making it to the outlet. 301 N. Howes Street, Suite 100, Fort Collins, CO 80521 1 970.221.4158 1 www.northernengineering.com ■� I NORNHERN West Range Fort Collins I Supplemental Drainage Cert. Memo 1 09.18.14 Similar to the roof drain discharge, the outlet pipe from the pond also ended up being subsurface due to the elevation discrepancy encountered in the field. Rather than having the water quality control and 100-year release orifices exposed above the pond bottom, these items ended up being buried in #4 aggregate as well. A vertical elbow was installed immediately upstream of the orifice plate, and a perforated riser with a grated cover was extended to grade. This still provides hydraulic control to limit discharge for the 80% percentile and 100-year events, while maximizing the use of the filter materials and available storage volume. The pipes almost function as underdrains in this situation. Photographs attached to this memo further portray the constructed facilities. Another adverse condition encountered during construction had to do with a discrepancy in the Structural and Architectural Drawings, which caused the column footing elevations to be too high. Parking lot elevations had to be adjusted accordingly, while still trying to ensure 100-year detention storage volume was provided. The required 100-year detention volume was calculated to be 2957 cu.ft., which was supposed to be provided at an elevation of 5001.4. The constructed pond was field surveyed, and the corresponding storage volume was found to be 2822 cu.ft. at an elevation of 5001.7. 95% of the design volume is provided, with the resultant shortage being only 135 cu.ft. A theoretical water quality capture volume (WQCV) was also computed during the design process. The full WQCV was calculated to be 461 cu.ft.; however, the approved design allowed for a lesser, "best available" quantity to be provided. It is recommended that a variance be approved to allow the WQCV to share space with the 100-year quantity storage volume (i.e., inclusive volumes rather than additive volumes). Such a variance would allow an effective water quality capture volume to occur within the limits of the bio-retention pond at an elevation of 5000.6. A stage -storage table is attached to this memo to document the as -constructed volumes. Not included in the listed volumes is any sub -surface storage that may occur in the void space of the #4 aggregate layer. Also excluded from the calculations are provisions for infiltration, adsorption, biological uptake, evaporation, etc. While not necessarily quantified, these items certainly provide further attenuation and treatment than the surface volumes alone would indicate. It is with these holistic stormwater management considerations in mind that the constructed bio-retention basin meets or exceeds the drainage design objectives. A well -constructed bio-retention facility can help mimic the natural hydrologic cycle and better support biodiversity than a traditional detention pond with a 40-hour dry extended detention basin component. This is a cornerstone of Low -Impact Development (LID) practices. Even though the West Range project was not subject to Fort Collins' current LID requirements, a sustainable approach to stormwater management was still pursued. It is worth noting that over 65% of the total project site, and 100% of the paved parking lot, is treated by the bioretention pond. Landscape buffers along the Laurel Street and Meldrum Street frontages provide further treatment, approaching close to 100% treatment by LID techniques. Page 2 of 3 NORTHERN West Range Fort Collins I Supplemental Drainage Cert. Memo 1 09.18.14 This project also preceded the City's latest Construction Inspection Checklist for Bioretention Cells. Nonetheless, the Contractor, Owner, and Engineer are voluntarily providing a completed checklist, along with construction photographs and supporting documentation. Not only will this confirm the adequacy of the stormwater management system for West Range Fort Collins, but it could help serve as a case study and template for future bioretention facilities as well. To summarize, field conditions encountered during construction caused a few items to deviate from the approved plans. While not explicitly per plan, the provided 100-year detention storage volume remains within acceptable tolerances. Perhaps of greater benefit is the significant water quality treatment and minor storm attenuation that will occur as a result of a well -constructed bioretention facility. There is almost a full -spectrum stormwater management component to this drainage system. Sufficient freeboard remains between the 5001.7 overtopping elevation north towards the alley and the 5002.9 finished floor elevation of the building to the south. Therefore, it is my professional opinion that the constructed drainage facilities at West Range Fort Collins fulfill the intentions of the approved design. Plan differences are relatively negligible, and do not pose a risk to the health, safety, or welfare of building occupants, or the public at -large. The bioretention facility in particular is expected to provide enhanced stormwater treatment and peak flow reduction to a significantly greater extent than the historic condition. Please feel free to contact me if you have any questions or require additional information. Sincerely, Nicholas W. Haws, PE, LEED AP Vice President enc. Page 3 of 3 ■ NORTHERN ENGINEERING West Range Fort Collins I As -Built Detention Volume Elevation Surface Incremental Incremental Total Vol. (ft) Area (ft2) Depth (ft) Vol. (ft') (ft') 4999.5 N/A N/A N/A N/A 4999.6 N/A N/A N/A N/A 4999.7 N/A N/A N/A N/A 4999.8 N/A N/A N/A N/A 4999.9 6 N/A N/A 0 5000.0 16 0.1 1 1 5000.1 29 0.1 2 3 5000.2 47 0.1 4 7 5000.3 72 0.1 6 13 5000.4 110 0.1 9 22 5000.5 299 0.1 20 43 5000.6 474 0.1 39 81 5000.7 630 0.1 55 137 5000.8 868 0.1 75 211 5000.9 1183 0.1 103 314 5001.0 1528 0.1 136 449 5001.1 1931 0.1 173 622 5001.2 2408 0.1 217 839 5001.3 2951 0.1 268 1107 5001.4 3556 0.1 325 1433 5001.5 4224 0.1 389 1822 5001.6 4979 0.1 460 2282 5001.7 5825 0.1 1 540 1 2822 301 N. 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N r2 O L u rn a` NORTHERN ENGINEERING West Range Fort Collins I Bioretention Cell I Construction Photographs Roof Drain Discharge Pipe - prior to aggregate placement Roof Drain Discharge Pipe - after #4 rock and pea gravel Roof Drain Discharge Pipe - after BSM placement Pond Outlet Pi Pond Outlet Pipe - after #4 and pea gravel Pipe - with perforated riser pipe Page 1 of 4 NORTHERN ENGINEERING West Range Fort Collins I Bioretention Cell I Construction Photographs Roof Drain Discharge Pipe - with cleanout riser in Discharge Pipe - with cleanout capped above Pond Outlet Alleft )/ grate and #4 rock to grade JA 7 -� Pond Outlet Pipe - cleanout/overflow riser (orifice Page 2 of 4 NORTHERN ENGINEERING West Range Fort Collins I Bioretention Cell I Construction Photographs Y ti • �Y 2 � L .:{ Bioretention Cell — prior to aggregate placement (subgrade ripping) Bioretention Cell — after #4 rock and pea gravel (geo-fabric edge) Y ��Y LpY WLti yr � A Fk , _Y l Ik r Bioretention Cell — pea gravel layer and tree placement Bioretention Cell — BSM layer and additional plantings Page 3 of 4 NORTHERN West Range Fort Collins I Bioretention Cell I Construction Photographs Bioretention Cell — BSM placement above pea gravel layer, note trees, plantings, and drip irrigation Bioretention Cell — beginning to place mulch above BSM, note initial rock forebay note rock forebays Bioretention Cell — final mulching and surface treatment, note rock forebay was modified for better performance Page 4 of 4 "EA1RZTtZCYCLE s111 To 3501 East Prospect Rd Fort Collins, CO 80525 Reliable Lawn Service, Brad 2920 E. Mulberry Fort Collins, CO 80525 Invoice Date Invoice # 7/31/2014 2014-11602 Delivery Ticket No. P.O. No. Due Date 7853 /7826 8/30/2014 Quantity Description Rate Amount 25 Retention Pond Mix 33.00 825.0OT 2 Delivery Fee -Tandem 69.00 138.00T 963.00 Larimer County Sales Tax 5.78 5.78 ; 5.78 State Tax 27.93 27.93 Tax item used for transactions created in QuickBooks POS 0.00% 0.00 I I THANK YOU FOR YOUR BUSINESS Total $996.71 Hageman Earth Cycle 3501 East Prospect Road, Fort Collins, CO 80525 970-221-7173 www.hagemanearthcycle.com Sold To: Person OrderinglPO* Phone: Payment Type: Truck Reliable Lawn Brad 97-222-8531 On Account Semi Date Order Taken: 7/22/14 start `Z 7 ; � Ttdcet � Mileage Time 7828 End Mileage Time Date: Time: (vVt Address: Meldrum and Laurel - NEW APPARTN7!!7 Qty hauls Ordered: Unit Price Amount BSM Delivery Charge $110.001 $110.00 s+aoluonaf oenvery tee Subtotal Gross. Tax 7.35% Tax Sub Tare.' Total Net: A p�/ HEREBY RELEASE HAGEMAN EARTH CYCLE, INC. FROM ANY LIABILITY FOR DAMAGES INCURRED WHILE RESS. ALL SALES ARE FINAL WITH CREDIT CARD PAYMENTAND/OR SIGNATURE ABOVE. Net due 30 day!--A4nan4 dti ge of 1.5% per month (18% annual rate) is charged to all past due balances DRIVER INITIALS: \ l,f / DEL.TIME: Instructions: Directions: 1. Mulbe Laurel west to College so rum on the north at Meldrum and 2. Prospect west to College north the Laurel, West to Meldrum and Laurel on the right. Hageman Earth Cycle 3501 Eas Prospect Road, Fort Collins, CO 80525 970-221-7173 www. hagemanearthcycle.corn Sold To: Reliable Lawn Person Ordering/PO#: Brad Phone: 97-222-8531 Payment Type: On Account Truck: Semi Date Order Taken: 7122/14 Ticket 7853 Date: , Time: AT--1 Address: Meldrum and Laurel - NEW APPAR Qty Items Ordered: Unit Price Amount, 12.5 BSM $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 Delivery Charge $110.00 $110.00 A=Vona/ vetrvery Fee Terms: Net due 30 day DRIVER INITIALS: T1- Durnping Instr_ uc ions: See Crew Directions: Subtotal $110.00 / Tax 7.35% Tax Sub $8.09 Total $118.09 HEREBY RELEASE HAGEMAN EARTH CYCLE, INC. FROM ANY LIABILITY FOR DAMAGES LESS DELIVERY ADDRESS. ALL SALES ARE FINAL WITH CREDIT CARD PAYMENT AND/OR of y.5%per month (18% annual rate) is charged to all past due balances — DEL.TIME: NORTHERN ENGINEERING Addendum to Overall Site Drainage Certification Date: October 9, 2014 Project: West Range Fort Collins 406 West Laurel Street Fort Collins, Colorado 80521 Permit No. B1304524 Attn: Mr. Dan Mogen, El City of Fort Collins — Stormwater Utility 700 Wood Street Fort Collins, Colorado 80521 Dear Dan: NE Project No. 875-001 This document serves as an addendum to the Overall Site Drainage Certification for West Range Fort Collins (WRFC) dated 09.18.14. It specifically addresses the shortage in stormwater storage volume. The City of Fort Collins Stormwater Criteria Manual requires 100-year detention quantity storage to be provided in addition to (on top of) the 80"' percentile water quality capture volume (WQCV). The as -constructed WRFC bioretention facility does not meet said criteria. Therefore, a variance is hereby requested to allow an inclusive WQCV that resides within the 100-year quantity storage volume. The 09.18.14 certification memo mentioned that the bioretention cell could be interpreted as a full -spectrum storage facility. While not formally part of the project design, the Low -Impact Development (LID) nature of the bioretention facility could have supported site -level volume reduction methods and a storage -based Impervious Reduction Factor (IRF). In the case of on -site detention, if the Excess Urban Runoff Volume (EURV) procedure would have been utilized (i.e., Full Spectrum Detention), then the Urban Drainage and Flood Control District would suggest that no additional volume for WQCV need be provided within the 100-year basin. This is not to suggest that the bioretention basin meets City of Fort Collins criteria, as it does not However, it helps to provide context and justification for the requested variance. Additional justification to support the variance comes by way of further documenting the assumed shortage. The constructed storage volume of 2822 cu.ft. roughly corresponds to a 90-year design storm. The excess 135 cu.ft. of runoff volume generated during the 100-year storm is expected to overtop and spill at a rate of 0.05 cfs (this assumes no infiltration or storage below the surface elevation of the bioretention facility). 301 N. Howes Street, Suite 100, Fort Collins, CO 80521 1 970.221.4158 1 www.northernengineering.com NORTHERN ENGINEERING West Range Fort Collins I Drainage Certification Addendum 10.09.14 The 100-year spill path is north/northeast into the adjacent alley. While there is storm sewer in the alley, it is assumed to be at capacity during the 100-year event. Therefore, the 0.05 cfs of excess flow from WRFC is expected to spill into the western flowline of Meldrum Street. A local drainage basin and 100-year gutter flow have been estimated at this location. The adjacent half - street has a major storm flow of roughly 15.93 cfs, and an approximate capacity of 22.1 cfs. Therefore, the 0.05 cfs of 100-year overflow from WRFC can be accommodated in Meldrum Street. Supporting documentation is attached to this addendum letter. Ignoring infiltration, adsorption, subsurface storage, and theoretical volume/impervious reduction methods represents the most conservative outcome. Even in this "worst -case" scenario, the resultant volume shortage and overtopping flow rates should be of little concern. Excess flow can be safely conveyed within public right-of-way at acceptable limits. The as -constructed drainage facilities are not expected to compromise the health, safety, or welfare of building occupants or the public at -large, nor adversely impact private property. Rather, the bioretention facility is expected to provide enhanced stormwater treatment and peak flow reduction much better than the historic condition. Therefore, it is kindly requested that the variance be granted and the certification package be accepted. Please feel free to contact me if you have any questions. Sincerely, Nicholas W. Haws, PE, LEED AP cc: Clint Hart - Brinkman Construction enc. Page 2 of 2 z 5 O < r OU��LL LLw �C)0OD 2O~C.,NIY H% Z L N O m 11 QWZ(n W�a�a� �COOW> W z LL w H 2 o Z J > W LL uj U' 3 � 0 = LL LL = U) r ~ LL ~ LD � O a a 0)Z0r-ate ui:)a 0< �IrLL F-UO O (0 1- w F- C) U WLL, W Z O W a C) °WCIO W fn N 1 > Q W O 5 o Q�Q W UOI,nY Z F J _ O \ Z W O 3 g>W> O W U Wm ZmZ W Q Q L U (-D Z F CO Q Z �1 X D AM 1 cn p ' C u I t p nQ J = y I F ew w W z r[�G1 0 000 F- LL LL U Q goy O QO O o4 � z a Z w� _ 111 F— l..l z o (' z M O O -� NORTHERN West Range Fort Col lint ENGINEERING Detention Pond Calculation FAA Method Project Number. Project Location: Fort Collins, Cola Calculations By: C. Snowdon DX,N 10/3/2014 Pond No.: Pond A Input Variables Results Design Point A Design Storm 90-vr Required Detention Volume Developed "C" = 1.00 WQCV IN 0 ft` Area (A)= 0.46 acreti 2822 ft; Max Release Rate = 0.50 cfs 0.0648 ac-ft Ft.Collins Inflow Storage Time Time 100-yr Q100 (Runoffl Outflow Detention (Release) Volume Intensity Volume Volume (mills) (secs) (inlhr) (cfs) (ft') (ft) (ft ) 5 300 9.65 4.4 1332 150 1182 10 600 7.49 3.4 2066 300 1766 15 900 6.32 2.9 2618 450 2168 20 1200 5.43 2.5 2997 600 2397 25 1500 4.83 2.2 3332 750 2582 30 1800 4.38 2.0 3630 900 2730 35 2100 3.96 1.8 3822 1050 2772 40 2400 3.63 1.7 4004 1200 2804 45 2700 3.35 1.5 4166 1350 2816 50 000 3,13 1.44 4322 1500 2822 55 3300 1 2.94 1 1.4 1 4459 1650 2809 60 3600 2.77 1.3 4593 1800 2793 65 3900 2.64 1.2 4733 1950 2783 70 00 2.51 1.2 4854 2100 2754 10/3/2014 3:42 DWrojects1875-0011DwglEngineerlSnowdon1875-001_90-YEAR Detention Pond .xlsmIFAA- Current idf (90) v NORTHERN West Range Fort Collin ENGINEERING Detention Pond Calculation FAA Method Project Number. Project Location. Calculations By. Dc 1 10/3/2014 Pond No.: Input Variables Results Design Point Design Storm 100- 7 Required Detention Volume Developed "C" = 1.00 WQCV 0 ft' Area (A)= 0.46 acres 2957 ft' Max Release Rate = n 50 cfs 0.0679 ac-ft Ft.Collins Inflow Storage Time Time 100-yr Qioo (Runoff) Outflow Detention (Release) Volume Intensity Volume Volume (miss) (secs) (in/hr) (cfs) (ft') (ft) (ft ) 5 300 9.95 4.6 1373 150 1223 10 600 7.72 3.6 2131 300 1831 15 900 6.52 3.0 2699 450 2249 20 1200 5.60 2.6 3091 600 2491 25 1500 4.98 2.3 3436 750 2686 30 1800 4.52 1 2.1 3743 900 2843 35 2100 4.08 1.9 3941 1050 2891 40 2400 3.74 1.7 4129 1200 2929 45 2700 3.46 1.6 4297 1350 2947 50 000 3.23 1.49 4457 1500 2957 55 3300 1 3.03 1.4 4600 1650 2950 60 3600 2.86 1.3 4736 1800 2936::A 65 3900 2.72 1.3 4880 1950 2930 10/3/2014 3:42-)PMgjectsl875-0011DwglEngineerl5nowdonl875-001 90-YEAR Detention Pond. xlsmlFAA_Current idf (100) ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) ed on Regulated Criteria for Maximum Allowable Flow Project: West Range Fort Collins Inlet ID: 875-001 Se= - T. Tam Tcwown ��It{'• Y�rx W TA I S _ C� rov V QwyOx/ a d 0s mum Allowable Width for Spread Behind Curb Slope Behind Curb (leave blank for no conveyance credit behind curb) iing's Roughness Behind Curb of Curb at Gutter Flow Line :e from Curb Face to Street Crown Width Transverse Slope Cross Slope (typically 2 inches over 24 inches or 0 083 ft'ft) Longdudinai Slope - Enter 0 for sump condition ig's Roughness for Street Section Allowable Spread for Minor & Major Storm Allowable Depth at Gutter Flowhne for Minor 8 Major Storm Flow Depth at Street Crown (leave blank for no) STORM Allowable Capacity Is based on Depth Criterion storm max allowable capacity GOOD - greater th.t storm max a!: -:-cable ean.icnv GOOD - creater th.0 Tay« = 10 0 h Se.« Wit 0 020 ne.Cw = 0 016 Hrut4i = Tciwm = W= S, Sw Sr, nctmrt 600 255 200 0.020 0 083 0 005 0 018 inches It It/ft h/ft hM Minor Storm Major Storm Tw = 25.5 255 ft dmout 6.0 120 inches ❑ check = yes Minor Storm Major Storm in S.7 22.1 Cfs given on shoot'O-Peak' .,.. C o. Meldrum Capacity xlsm. O-Allow 10/3/2014, 3.41 PM il I I I I I I I I I I I I I I I I I I I I I I I_ I I I I I I I I I INV (AD - (E) - E DmNO W MV (s) ♦9 My (W9 - 49wM dove ALL I ®^^ AM BUL LK ALL MR ALUMINUM, 197% _AAA LM AN PLAT Arsr AS1FAAC=�T nAB3 L AN 2 ONi eR To mMWA LF _ `vW IP=MM "A ATRrrroWAy iYR 8000`II U v�M�l z i M LF O O.S11 PHI EPSILON HOUSE ELECTRIC ILERS- 1 I CORPORATION 412 W. LAUREL ST. wm uxwi T V0 P 61vi I I I O6s'nTw ELECTRIC. i l , vwu Cl• IR IlP0.pWABE t1 I� ASAULi PAICNMG I I . I W14 (SEC xDIE r) ♦. . y I MMO _E1(:PAIAi,_ _ ! --S 1 t EAEEYENC I U \ Y y \ I YI9W%2 RAM ^ \ 1• _ 1 � _ t YLaD STEM ABOLE I SECOiI sLvw A 1 L A.D.E -v L TRAIrY.I -- RAM LIFAIEDUTI ; P LOT I.rI mwT BE RF wm.a • LaNECT TD A- A RaDF LEADER ET . NEPAL 6 NONE 71 UP O 0.5[ EW IJ INNX XANMT • 1BTZI DPE RR HE 0O.5N _� WT.B. r s IEIENS �S.WIARY SEMER 5'ANCL LOT 1 AwRDWAtE xV ABeBn BLOCKI PROPOSED "AA - MULTIFAMILY \!X BUILDING 9 DOMESTIC Ymzs` `� -r----lam 1 MM ENTRANCE- Y UM DRIFT. ED BE RELOVED AAAAAAA —.- - - -_-_. _ S. ` - PRmG4n BE BETWMED SDEWUN R INS - — -- - INSTAL.- NEPNCF ALL - - Y IFIFA owACEn cyLB /LXNRe TIER ®'�spe AAA— AaT PFSMIHINCAND min RE£ RULE 7) _ ~ENERNI W. DIE (E)-,W681 D 1q 1 C W1fA Y.W LIT YET4 PPQ ��11 W. LAUREL STREET YR�" (VARIES)MI PAR 0 Lv "MR I SERNCE ru a: K D Op C W $ J N= XSTALL AS'MAN) Y/ id Al H4CS . EnS1 SANITARY AN MM - SONUM INV (N) = RAM 93 IRA LIAR IN V, (W) - 49E6.83 (Y CLAY) NV. (S) - 4ovi ING SWEARV w - 51 IN) - H 5.5E (BE PVC) (0 - Y91 (T P\E) GRAPHIC SCALE: 00 wz ® NORTH m 30 0 E0 w 6DFw1 IN MET ) I Mn - zD x. LEGEND: _ PRDRIBLY BOUNDARY - - r B PROPOSED WARR LINE w/ PIPS o PROPOSED DOMESTIC SERNCE LID .p j PROPOSED ARE SEIMCE -- 71 PROPOSED SidM1 MAIN 1 At EXISTNG BURIED FIBER -OPTICS Cry Q ALL EXISTING BURIED ELECTRIC LAI BURIED Ws c 7 ¢S CAUSING WATER UNE w> > O EXISTING BURIED TELEPHONE T WSTNG OLFAXEAD VTUTY --- - EXISTNO SwITARY SEWER WE W/ YHc fXI6THG sttRN E[WFR UXE W/ YX �51�EXISTMG RATER ane STRIP UOUSTING WATER VALVE HD EXIST IG WATER METER EXISTING ELECTRIC VAUNT EK METRO GAS MERR (� EXISTING TRAFFIC MCMAL POI£ UW: Z/ CD R EXISTING CABLE PECESTAL EXISTING MEET GRATE XY IX w l EWSTNG 9fY1 LZ� yJ EASING LIGHT AGREE ! r Z GA EXISTING PDWER POLE 'yDLa ED w E LAI CBNXMMUS SHALL BRF. O Z fi LAI CCUDUCKUS TREE O Z W L NOTES: THE APP IRE AND W WHEN SHOWN OF THEMDR UMENWANGS. IT SHALL UMPIRES BETH }� I ARC ONANUYAR TY OF THE CONTRACTOR TO CY RY THE EXISTENCE FNF EREMPd WOERWOIUND UTTLI F A TRARM iO NMEY 1XE STOREOF ALL ES W THE AREA OF CTHEONTRACTOR WORK, II BE G8 L CDIMONSHG NEW CONSPUOUI G ALL UXE GROU D U11 91Au LS B= RESPONSIBLE MOOR All- CA G ALL UNDERGROUND UTILTIES AND SHALE- BE xEsowvBLE EM ALL uxxxoxx MNBMMaxO UTILITIES. z Au AND SEWEET R CONSTRUCTION SHALL BE PTHE CITY W EMT W GOLAN WARR CSTGVCnM sPEClnM cnnS PALEST MITI. 3 ALL WATER FIRINGS AND VALVES ARE ONLY GRAPHICALLY REPXEMONTED AND ARE NOT TO SCALE. .0 ya AL UTILITY SERVICES ARE SHOWN IN A SCHEMATIC FASHION ONLY EXACT LOCATIONS ALL BE PER MREQUIREMENTSEREQUIREMENTSM ENEHTS OF E RESPECTIVE CREEP %F_ M ONDERE AND ARE SUB{CT i0 CHANGE IN THE FIELD. s. MOUNTAIN 10HORIZONTAL AM IV VERTICAL MINIMUM SEPARATION G BETWEEN ALL SANITARY SEWER MAINS. WARR MAINS A DRAMS 6. ARE LUXES SHALL BE ARMED INSIDE THE RISER ROOM AND CAPrFD 1' R j ROVE THE FINISHED RODE ELEVATION. TT d UWTM Or STREET CUT ARE PROXIMATE FINAL LIMITS ID REBE DEMEANED im �tion IN F FIELD BY WORE CI GNEERING MSFECTOR. L PARS DN IN ACCORDANCE IN CITY STREET REPAIR STANDARDS. B ALL EMSTIINO STANDARD C SANITARY SEWER YRNCES SHALL LATEST LMON BY GwFRA 1 INWES A UNITARY ABANDONED AT TINE MANCA PER CgTM. EMT GCW NS CONTRACTOR i0 CMRdNAE THE MARCONI OF THE EXISTING TWO RR YRNCES MM THE CITY CE EMT LULUS UTUTES AT (970) 416-21M MOOR TO CONSTRUCTION, CALLUMPYNOTILICATIONCENTEROF � aRnoo X,9,,WAbelow. N.HU CaKKI wW REPAIR FOR o<: Street C2.00 Of 15 Sheets GRAPHIC SCALE EIM1STM° r COEK2 PIN PUBLIC ALLEY 3EE DEPaLED _ LAIgBC+pE WmL Izo wollr-DE-wAr) cluolNCE • /— a - gMFR `I z' a OUT • yn y_ EIo aRe AFFAIIII $Q • I h/ FAYIOIT� � WRWNWN z CAWS PAN IQ yM �iJ b ass ERNu _ I I i cum \ I , IPr E6GY0 / 1 ARN�NG� — 1 wwnw.nF F - 1 P wruneclaTRnPIn j `\ , FMAxrnws[ 1 , ImwBUABWn , \\ w�OFRa 1 Ewwa 1 L 1 -� SEE DETNLED GRADING8 f I W jwY a I A VERTICAL CURB e QUTTER 0 SEE MAILED R' re GRADING 02 RNL Ly 2 S EASEL ANum D vmspourr _ E CUMM M acre O. I ' SEE DUFF ED - GRADING D H. Anu !I BLOCK I `.:P RAMIFIFROIDONSEDFUMILY BUILDING ,D- IF A e- �a q CBMI J �RI► r---- ---a----^ ---------------- -�� 1 DUTY 1 1 CONCRETE ooNarz [MANOR MILE / 1 - -- --- 1 1 1 1 u IE ENCLOSURE FFE-2AFF4.91, 1 1 1 1 1 1 _ 1 f- L --ING FF DETAIL_ GRAD SCA E 1-- 5E W. LAUREL SI (VARIES) r-rRRIIAIR -I-WIN m----- w w SIR SIR SIR -=1 1 1 Q 1 I 1 1 I 1 1 G 1 I 5 1 I i e¢aMD 1 1 1 1 Ba' 1 1 1 r-Rr CURB V6 1 PAD-a.11 IIRSIII L 1 I , 1 ElEcmc 1 IMClVGEWER CONpEIE PAD ; L--- J -Pg.2.2fleWm - DETAILED GRADING E YwLE1'-5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ' L--- WING G 1 1 1 1 1 1 1 1 /1 I , DETAILED GRADING D SCALE 1 ® NORTH 20 0 w w BD Pwt (IN FEET) 1KKA- MR. LEGEND: PROPERTY BENAMY EASING STURM SENIOR LONE W/ w "STING INST GALE • PROPOSED CONTOUR qy CAGING CwnOLw PROFgYD SMILE PROPOSED PRIDM CURB It ENDER AGRI PROPOSED ONB4L Cum s aTq PROPOSED RIMON CURB = PROPOSED ROOF LEADER L PROPOSED CURB MANDATOR Al`' PROPOSED SPOT REMAIN •y FOANW. SPOT P1NAIMN Y PROPOSED SLCP6 0_ TGP OF ROLE EEVATON LORD FINISHED GRADE ELEVATION FO TOP BACK OF CURB ELEVATOR INC 1101M E E CZE TIRE Mn LCCAnCN u OF AKNOWN UNDERGROUND nuTES ARE APPRoxMUTE MEN SHOWN ON THEY BODRPMNGS 17 ALL BE THE RESOONSIB urY a ME CONTRACTOR VESSEL ME EYSTE FE BE ALL UNDERCRaxU U IL nEs ME AREA OF THE WORK E COMMENCING NEW CONSTRUCTOR. ME CONTRACTOR SMALL PDN9BLE FOR LOCATES L UNDERGROUND TES AND SHALL BE RESPONSIBLE FORFOR NUNDERGROUND UTILITIES, a PREFER TO THE FLAT FOR LOT AREAS. TRACT SIBS EARMUFFS OFFER SURYEYSNFORMATION UTILITY EASEMENTS. OTHEREASEMENTS. AND ALL PROJECT DATA IS ON THE BE EMT COLLINS xs RTCA- } GrvCOLLINSBAADEN NN (UNADJUSTED). SEE CONER STEET FOR BENCHKA REFERENCES • Au CURB SPDn ARE ELONUK ELEVATORS UNLESS DINER AIM NOTED. &I OFFER V07S ME HESLER MADE EIFVATMS 5 A XDISTURBED AREAS SHALL BE REKGATEATED PER ME oscwE PLANS 5 CONTRACTOR SHALL ENTER TO AND mMONATE WHOM THE APPROVED LANDSCAPE PLANS FOR DETAILED HARDSCAPE RESIGN AND EFTS FEATURES SUCH AS RUDE RAIXS BENCHES TRASH AECEPTACI£5 DSCAR PORN AND MULCH, LANDSCAPE WALL CONSTRUCTION MTALR STAR AND HANDRAIL DETNLS AND SPECIFICATION, AND 9gAGE AND STERLING O�w `NCFryr O o 'iriytik Dm� OB.OR:34 ftE INF© L1' (SE Old cuLUT rvCLORADO waN xGCO RRMIow. IP.S.W MORE 0 OFF A CALL 2 PLANES DAIS I ESPOREAD �TyR OR z ^J LL 0 z QN� /LLB V J qJ LC 0 Sheet C3.00 !)f 15 Sheets CLASS A BEDDING CUSS B BEDDING �m.cr MARC` n.xua` Je.w sw .s C,EER ETHIC OR INSIST SAN BE lx� w w Mx + w� L�� /Im ID MY m.._i Yme CONCRETE AN MIAMI 14 x , "RIVALS. 6. CUSS C BEDDING ROCK EXCAVATION i,r<< ww.,_�� 7 .oY. �L'i/' ANII CONVICTED unrtnu 9N, UNSTABLE SUBGRAUE SUBDRAI\ NLI W Taex SEEN u m[em TRENCH ,- OF v�pl}SELL -..- LEASE LOT IF IN, a j SLIREE amu .. MARIANA THWART, I i. IIIEHEWL aeR mnm ere ISEC,E / uHLLk rzn ADD NORT'. _ n s SEumumw IFSTORM) MONARCH r. STORMB'ATER BEDDING REQUIREMENTS HIIIIGr1��ll SI'ORYIIATER ar. CONSTRUCTION DETAILS D— I CEE-E OR TOM COLLINS CRESEARREL cu.A . ERxr.Ya.ar...�..�.am�....r..e..w. ..,WM��I.. '�:a.d.. �r.Z`I.rd°:.i m�..1.w..Ww... w...."w o. s....w..a ". a .. w.w"w-.. ......°.."... a"".�"....o..w..�Y w aa�wmwammn.aYwnravrvuu. ., caTRIPS, :....w. .....®n..®......ww+w.a.d,�..w,.�w EN d� A .d..+. N.r...�.....aa-Yx x.. r a-P�Yllu' owwq•IW+ xx �. mw...x..W w...,...�..�,..�. 1 - BIORETENTION SAND MEDIA SPECIFICATION CSD TRENCH YSECTION Sm NNO MiW v:v. . �\ ItMM �K AIDS YP 1 .IXMDa n/.�i.>�. v. T,/ qv BEDDING REOUIRMENTS CrWfY��llln SE12N CONSIRUCTLON IMMAR' �i-l`^ `✓�^�^�"'�'� OCTANTS yu/u W W I 6Arme'`rm NI`m"'virr DAMINCLINED NDNO RELY mmAz CDRffRXXXA1 wmwau 1 ATE RMF dD EVENING AN WILL NW gI11TT STAVES SYG` IxcxM axis/ R13• ac. uM. ORIFICE PLATE SUMMARY TABLE STNnCTLINE ON"' NOADWALL tn- C RT x d-tn• IMERT M) I1 C o aIM t"Fvl¢ vt [MNEELLDDIG PIK BEDDING 0 SEASE �TED MADE END LEAD LIENCKIE SH B Ix AN,S[v@ %>[ PLAN VIEW TRENCH � M v IS AS HOPE RE, SE i[i[x clrt ASANE AN rORRE IT I, W COMPACTED TIS °� ISAN CONCRETE CROSS VIEW MON WRITE COMPOUNDS 1 ALLOWED M vll SERVICENNEDETAIL uI� SERER CONSTRUCTION P=m DETAINS Vtl/It WW-B s QUTRR BOLOS. TO MEa61TMNE 11g1 SAND ICINP SPCCIEICATNMI ROSEMq£ xFW SCHL MIX z 00-RETMTIM SAND LOSS 5M41 BE FRDNOm BY HAD M ENO LITTLE OR ARXOT£D SWAL �1 TYPICAL BIO-RETENTION SECTION CROSS SECTION OF STORM TERMINATION AND OUTLET PIPE �� w rA, NALIN SAW MWEq STSWETAI AN CO HAS) OwACE 0. WIN IWALt SORT WATER CREEP FLOW DI nM TRAFFIC RIMED CLEMIgR SEIEER CONSTRUCTION 0 DETAIIs S^'^' W-1 WW-15 I HIS S-6- WORKED METHOD S-AT D[ax[ssD Dlmm S-V WARPED DETrtx Y E r DP m cup 3 HdiMAL RDAUIE� _STAMARO MRPCA MYTH DAND e' e < WTIFAim a arzl¢D novAlllE IBBGRVOTNAL_a6TYB tl+A YTun xDTSKwTIax rnIRR DE CMDRADD • IfII.11M1Y 2- MIERIC13CM HALT 6 MAN City of Fmi Collin: UTILITY PLAN A C5.01 Of 15 Sheets