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HomeMy WebLinkAboutDrainage Reports - 10/05/20061 City Of Ft. Collins Approved Plans - Approved By NW6 ' FINAL DRAINAGE AND EROSION CONTROL REPORT FOR INNOVATION ISLAND ' Prepared for: Habitat for Humanity 4001 South Taft Hill Road Fort Collins, CO 80526 ' Ph. 970.223.4522 ' Prepared by: Interwest Consulting Group 1218 W. Ash, Suite C ' Windsor, Colorado 80550 Ph. 970.674.3300 Fax 970.674.3303 ' September 6, 2006 1 ' Project No. 1029-026-00 1 INTEERWCBT = CONSULTING GROUP [] 1 1 INTERWEST M CONSULTING GROUP 1 September 6, 2006 1 Mr. Basil Harridan City of Fort Collins 1 Stormwater Utility 700 Wood Street Fort Collins, CO 80521 1 1 1 1 RE: Final Drainage and Erosion Control Report Innovation Island Dear Basil: We are pleased to submit for your review this Final Drainage and Erosion Control Report for Innovation Island. This site is located in the southeast comer of the intersection of Harmony Road and Taft Hill Road. All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria. We greatly appreciate your time and consideration in reviewing this submittal. Please call if you . have any questions. - 1 Sincerely, 1 1 1 1 1 Robert Almirall Project Manager Colorado Professional Engineer No.33441 O T Uo., At4: 49� a : 33441 F IVAI e'tN* 1218 W. ASH, STE. C • WINDSOR, COLORADO 80&% TEL 970.674.3300' FAX. 970.674.3303 1 I Fri ' TABLE OF CONTENTS PAGE TABLE OF CONTENTS ii 1. INTRODUCTION..................................................................................................................1 1.1 Project Description..........................................................................................................1 Figure1— Vicinity Map............................................................................................................2 1.2 Existing Site Characteristics...........................................................................................2 Figure 2 - Site Photo looking west..........................................................................................2 ' 1.3 Design Criteria................................................................................................................3 1.4 Master Drainage Basins and Offsite Hydrology..............................................................3 1.5 Variances from Criteria...................................................................................................4 ' 2. HISTORIC (PRE -DEVELOPMENT) HYDROLOGY......................................................4 Figure 3 — Existing Downstream Concrete Channel north of Seneca Drive ............................4 3. PROPOSED (POST -DEVELOPMENT) HYDROLOGY & HYDRAULICS..................5 3.1 General Flow Routing.....................................................................................................5 ' 3.2 Hydrologic Computations...............................................................................................5 3.3 Hydraulic Computations.................................................................................................6 ' 4. STORMWATER DETENTION & WATER QUALITY TREATMENT .........................6 4.1 Stormwater Detention.....................................................................................................6 Figure 4 - Existing Regional Detention Pond.........................................................................7 ' 4.2 Water Quality Treatment.................................................................................................7 4.3 Outlet Structure Design...................................................................................................8 ' 5. EROSION & SEDIMENTATION CONTROL...................................................................9 5.1 Erosion and Sediment Control Measures........................................................................9 5.2 Permanent Stabilization..................................................................................................9 ' 5.3 Maintenance....................................................................................................................9 6. REFERENCES......................................................................................................................10 APPENDIX: A - Maps and Figures B - Hydrologic and Hydraulic Calculations C - Detention Pond Analysis D — Water Quality Structure Design, EDB and PLD ' E - Erosion Control Calculations & Surety F - Excerpts from other Reports 1 1 1218 W. ASH, STE. C' WINDSOR, COLORADO 80550 ' TEL: 970.674.3300 • FAX 970.674.3303 I 1 ' 1. INTRODUCTION This Final Drainage and Erosion Control Report describes and provides supporting ' calculations for the proposed stormwater management system and the erosion and sedimentation control plan for Innovation Island. This plan is intended to limit the impact of ' the proposed project on the natural water flows and on air quality during construction and throughout the life of the proposed buildings. Stormwater management measures include a ' combination of Best Management Practices (BMPs) which control the quantity and quality of the rainfall runoff from the site. 1.1 I 1 1 I 1 Project Description Innovation Island, hereafter referred to as "site", is located in the southeast corner of Harmony Road (County Road 38E) and Taft Hill Road in southwest Fort Collins, Colorado. More specifically the project lies in the Southwest %4 of Section 34, Township 7 North, Range 69 West of the 6 h Principal Meridian in the City of Fort Collins, Larimer County, Colorado. The site is bounded by W. Harmony Road on the north and east, S. Taft Hill Road on the west, and The Overlook at Woodridge Fourth Filing on the south. A water pump station owned by the Fort Collins -Loveland Water District borders the northeast comer of the site. '.o Ohio mai,na PI NWang Ln r+ c v u 1M1mb°q D Ba°I.�PI _3Be D\ \e\aea�al°PAC\ N ec hmf.a Dy.n 0 ��I1I1''1IRR P���w�r�ryPryPl``e�� SaD. Cf pia E QNMLIC Di •v\f'n HPnn CUK Cf % Rn Mn Re _ flann I �D i vj°�yn YRd 6aL Ra y a Iia'a 4YOi Iv.'0•1. _ F w..p.imn - e.ero�e c� s. .,.r Q a t �d•O'f°O °. ••1: lea c ® . arne.,n D� c � F—rn.R--war wRe Puln...eP. D, n• c\ 4 Old. Sap. Dr ,y^vim • 3 3i 2 o'v�• o Final Drainage and Erosion Control Report Page 1 ' Innovation Island September 6. 2006 I �l Figure I — Vicinity Map ' The total size of the Innovation Island site is approximately 4.4-acres and it will be divided ' into two lots. An Overall Development Plan for the entire 4.4-acre parcel was previously approved. This report includes the stormwater system plans for the west lot which is approximately 3.2-acres in size and will contain 27 multi -family units and a small park. The east lot is approximately 1.3-acres in size and will be sold separately as commercial development property. This report details the proposed storm water conveyance and water ' quality treatment system for the 3.2-acre multi -family development on the west side ' 1.2 Existing Site Characteristics The site currently consists of open space and is sparsely vegetated with native plants and ' grasses. 1 I L' 1 ' Figure 2 - Site Photo looking west Existing swage along south border The soils in the area are predominately Renohill clay loam, 3-9 percent slopes (soil number 90) and Fort Collins loam, 1-3 percent slopes (soil number 35) as reported in the Soil Survey of Larimer County Area, Colorado. Renohill clay loam has rapid runoff and severe water erosion hazard. Fort Collins loam has slow runoff and moderate to slight hazard of wind and water erosion. Final Drainage and Erosion Control Report Page 2 ' Innovation Island September 6, 2006 I I [1 I I I 1 1 The site is located outside of any Federal Emergency Management Agency (FEMA) designated floodplain. The applicable Flood Insurance Rate Map (FIRM) is the City of Fort Collins, Larimer County, Colorado, Community Panel Number 080102 0003 A, revised February 15, 1984. The site lies in Zone C, areas of minimal flooding. A copy of the FIRM map is included in the Appendix. 1.3 Design Criteria This report was prepared to meet or exceed the submittal requirements established in the City of Fort Collins' "Storm Drainage Design Criteria and Construction Standards" (SDDCCS), dated May 1984 and revised in January 1997. Where applicable, the criteria established in the "Urban Storm Drainage Criteria Manual" (UDFCD) dated 1984, developed by the Denver Regional Council of Governments has been utilized. In accordance to the City of Fort Collins SDDCCS guidelines for residential multi -family zoning, the initial or minor storm return period of 2-years and a major storm return period of 100-years were used for the stormwater management system design. In general, the initial storm drainage system includes curb and gutter, storm sewer pipes and storm inlets and its purpose is to minimize inconvenience and protect against recurring water damage. The major storm drainage system includes overflow swales and stormwater detention facilities and its purpose is to eliminate substantial property damage and loss of life. 1.4 Master Drainage Basins and Offsite Hydrology The site is located on the upper end of the Mail Creek Drainage Basin. This site is known as sub -basin 89 in the master drainage plan and there are no offsite flows that pass through this site. Excerpts from the "Mail Creek Basin Baster Drainage Plan Hydrology Technical Appendix" are included in Appendix F of this report. This site is also included in the "Master Drainage Study for Woodridge" (1991) and the "Final Drainage and Erosion Control Study for the Overlook at Woodridge, Fourth Filing" (1995). In the Final Drainage Report for the Overlook at Woodridge Fourth Filing, this site is known as Basin 1 and 2A. Fully developed commercial flows from this site were considered in the stormwater system plan design for the Overlook at Woodridge. Details of the site specific drainage are included in the Section 3 of this report. Final Drainage and Erosion Control Report Page 3 Innovation Island September 6, 2006 I I 1.5 Variances from Criteria A variance is hereby requested to allow a small portion of the site (0.8 acres, a portion of Basin B) to be released without water quality enhancement. The area includes landscaping ' and a small amount of sidewalk and street. More information on the water quality enhancements proposed for this site is included in the following section. 2. HISTORIC (PRE -DEVELOPMENT) HYDROLOGY ' The southern portion of the site drains to an existing Swale which carries stormwater runoff along the south property line to a depression and into a concrete pipe located in Tract A of the Overlook at Woodridge. The remaining portion of the site drains via overland flow to the ' curb and gutter along Harmony Road and into two existing 15' type R inlets on the south side of Harmony Road. All of the stormwater runoff from the site is conveyed to the existing ' stormwater conveyance system in Harmony Road which passes to the existing concrete lined drainage channel north of Seneca Drive and then to the existing regional detention pond ' located adjacent to Webber Jr. High I P I r i I Figure 3 — Existing Downstream Concrete Channel north of Seneca Drive Final Drainage and Erosion Control Report Page 4 Innovation Island September 6, 2006 Ci 3. PROPOSED (POST -DEVELOPMENT) HYDROLOGY & HYDRAULICS ' 3.1 General Flow Routing ' The site hydrology was analyzed in order to size the proposed water quality pond and the drainage Swale on the south boundary of the site. The proposed site generally follows the existing drainage patterns and is divided into four major drainage basins as follows: Basin A includes the majority of the proposed site and a portion of the future commercial development to the east. Stormwater is conveyed via overland flow and gutter flow to the proposed drainage swale that runs west to east along the southern property boundary. This ' south swale discharges into the proposed Extended Detention Basin (EDB) in the southeast corner of the property located at design point 1. The outlet pipe for the EDB discharges to the existing storm drain inlet located on the south side of Harmony Road. Basin B includes the northwest comer of the site and half of the roadway of Harmony Road. This basin is conveyed via overland and gutter flow to the existing 15' Type R inlet in Harmony Road located at design point 2. Basin C includes the northeast portion of the site and half of the roadway of Harmony Road. ' This basin is conveyed via overland and gutter flow to another existing 15' Type R inlet in Harmony Road located at design point 3. ' Basin D includes the north portion of the building roofs adjacent to Harmony Road and the landscape area that will drain to and including the proposed porous landscape detention ' (PLD) areas. The PLD includes a 4" perforated PVC underdrain which connects to a 4" solid PVC outlet pipe which in turn daylights into a sidewalk chase and 1' concrete channel. The ' channel then flows to a crosspan across the entrance drive through a 2' curb cut and then into a 2' concrete channel which discharges to the south curb of Harmony Road and then to the existing 15' Type R inlet at design point 2. ' 3.2 Hydrologic Computations The Rational Method was used to determine the 2-year and 100-year peak runoff values for each Basin per guidelines in the SDDCCS Manual. Runoff coefficients were assigned using ' Table 3-2 "Rational Method Minor Storm Runoff Coefficients for Zoning Classifications" of the SDDCCS Manual. A conservative "C" value of 0.85 appropriate for commercial uses 1 Final Drainage and Erosion Control Report Page 5 ' Innovation Island September 6, 2006 n J I 1 1 3.3 1 F was used for Basins A, B and C. A "C" value was calculated based on relative areas of landscape, building, and sidewalk for Basin D. All hydrologic calculations for the Basins shown on the attached drainage plan are included in Appendix B of this report. Hydraulic Computations Hydraulic calculations for sizing the proposed Swale along the south site boundary were completed. The Swale is sized to convey 133% of the 100-year flows from the site. Sizing of the outlet pipe for the PLD and the EDB is included in Appendix D. Other Hydraulic calculations are included in Appendix B. ' 4. STORMWATER DETENTION & WATER QUALITY TREATMENT 1 4.1 Stormwater Detention Developed commercial flows from this site were accounted for in the design of the storm drainage detention pond for the Overlook at Woodridge Fourth Filing (1995). Since the time 1 that the Final Drainage Study for the Overlook was completed, the City of Fort Collins (CFC) has modified their stormwater design criteria to include stormwater quality 1 enhancement requirements and the use of a larger design storm based on a 1998 precipitation study. The peak discharge using the old rainfall data for the site only (4.4 acres) was 1 calculated to be 39.6-cfs. The required detention volume under the new rainfall conditions with a release rate set to the peak discharge under the old rainfall conditions was calculated. 1 The result was a detention requirement of 0.06 ac-ft with a storm duration of 5 minutes. Since water quality is being provided for this site (see following section) with a calculated release over 40-hours, adequate stormwater detention, in essence, is being provided for the 1 short, first flush of rainwater. Therefore, additional detention is not required based on the increase in the design rainfall rates. ' The downstream capacity of the stormwater system was also considered in determining if 1 detention would be required for this site. As stated in the previous section, runoff from the site enters the two existing 15' Type R inlets along the south side of Harmony Road. The ' upstream inlet was designed with the Overlook at Woodridge, P.U.D. Fourth Filing and it is known as design point 10 of this report. The designed peak flow to this inlet was Q(2) = 5.1 cfs and Q(100) = 17.6 cfs of direct runoff. The calculated peak flow with the Innovation Island site is Q(2) = 3.05 cfs and Q(100) =15.1 cfs. The difference in the peak flow rates is due to more accurate time of concentration calculations with the detailed site layout for 1 Final Drainage and Erosion Control Report Page 6 Innovation Island September 6, 2006 1 Innovation Island. The same results were found at the second 15' Type R inlet which is ' known as design point 21 in the Woodridge plan. Thus, the downstream conveyance system is adequately sized to handle fully developed flows from the Innovation Island site under the ' minor and major storms and additional detention is not warranted. 1 F J n Figure 4 - Existing Regional Detention Pond Adjacent to Webber Jr. High ' 4.2 Water Quality Treatment Water quality enhancement is being provided for fully commercial developed conditions for ' Basin A and Basin D. This includes the majority of the multi -family portion of the Innovation Island site, including all of the buildings, and the future commercial site on the 1 east side. Three water quality enhancement measures will be used with the primary water quality enhancement method being an Extended Detention Basin (EDB) which is designed using guidelines set forth in the Urban Storm Drainage Criteria Manual, Volume 3 (2004). The proposed EDB is a sedimentation facility which will capture stormwater runoff from frequently occurring rainfall events and extend the emptying time to allow for pollutant removal through gravity settling. The EDB pond is sized to treat runoff from Basin A plus the portions of Basins B and C south of the existing sidewalk along Harmony Road (3.9 acres total). This will allow the future commercial development to drain to the proposed pond without reshaping or redesigning it. Calculations for the required water quality capture volume are included in Appendix D. Final Drainage and Erosion Control Report Page 7 Innovation Island September 6, 2006 The second water quality enhancement measure is the use of two small porous landscape ' detention areas north of the proposed buildings along Harmony Road. The PLDs have an average depth of 7" with a minimum depth of 6". They have flat bottoms and will contain ' landscape plantings in a 18" deep sand/peat mixture. Water will be held in the depressed area and slowly drain through the sand/peat mixture and then hit a 4" perforated pipe in ' gravel bedding which will discharge ultimately to Harmony Road. Information on the design of the PLDs is included in Appendix D. The third water quality enhancement measure is to minimize the amount of directly connected impervious areas by detaching sidewalks and passing water through grassy swales ' to prior to entering the EDB. The bottom of the smaller swales and the low flow channel of the EDB will not be concrete lined in order to further enhance pollutant removal. A ' permanent micro -pool is not being provided in order to minimize maintenance costs for the Habitat for Humanity homeowners. Thus, in between stormwater events the majority of the basin will remain dry. There is a small portion of the site immediately adjacent to Harmony Drive which will not pass through the EDB facility but will flow directly to the street gutter and into the stormwater system. The majority of this area is landscaped with grass and plantings and only ' a small amount of impervious area from the sidewalk is included. Since the source of the majority of pollutants in stormwater runoff comes from driveway and parking areas, this ' small amount of untreated runoff should have a negligible effect on the overall pollutant load. ' 4.3 Outlet Structure Design The proposed outlet structure is a drop box structure with a flow control plate designed to ' release frequently occurring storm events over a 40-hour period. The top of the drop box structure is equipped with a grated inlet that will pass the 2-year storm. The outlet pipe for the drop box is an 18-inch reinforced concrete pipe which will be connected to the back of the existing 15' type R inlet on Harmony Road. The outlet structure grate and the 18" RCP ' outlet pipe have capacity to convey the minor 2-year storm peak flows. In case the outlet is plugged, an emergency overflow spillway will pass the 100-year peak flows on the north side of the EDB and onto Harmony Road. Detailed design of the outlet structure is included in Appendix D. Final Drainage and Erosion Control Report Page 8 Innovation Island September 6, 2006 J 1 5. EROSION & SEDIMENTATION CONTROL 1 5.1 Erosion and Sediment Control Measures 1 The erosion and sedimentation control plan for the site meets requirements for development in the City of Fort Collins and meets or exceeds those set by the United Stated Environmental Protection Agency (EPA) Document No. EPA 832/R-92-005 (September 1 1992), Stormwater Management for Construction Activities, Chapter 3. The purpose of the erosion and sedimentation control plan is to limit the overall sediment yield and reduce the 1 negative impacts on air quality during construction. 1 Measures in the proposed plan for Innovation Island include the use of a silt fence around the west and north perimeter of the site, straw wattles within the swale on the south border of the 1 site prior to installation of the concrete trickle channel, inlet protection around the proposed and existing inlets on the site, a gravel construction entrance at the main entrance onto Harmony Road and seeding and mulching other areas on site. During overlot and final 1 grading, the soil will be roughened and furrowed perpendicular to the prevailing winds. Erosion control effectiveness calculations, rainfall performance calculations and a 1 construction schedule are included in Appendix E. 1 5.2 Permanent Stabilization A vegetative cover shall be established soon after grading is completed in order to reduce 1 erosion and prevent the movement of sediments from the site. Suitable vegetative cover includes sod or using cover crops with mulch. Mulches that can be used include grass hay, small grain straw and processed materials such as erosion control blankets. Vegetation will 1 not be considered established until a ground cover is achieved which is demonstrated to be mature enough to control soil erosion to the satisfaction of the City Inspector and to survive 1 severe weather conditions. Contech Pyramat or other approved turf reinforcement matting is required at the outlets of all proposed stormwater pipes in order to prevent soil. erosion and 1 undercutting of the pipes. 1 5.3 Maintenance All temporary and permanent erosion and sediment control practices must be maintained and 1 repaired as needed to assure continued performance of their intended function. Straw bale dikes or silt fences will require periodic replacement. Sediment traps (behind wattles) shall 1 Final Drainage and Erosion Control Report Page 9 1 Innovation Island September 6, 2006 be cleaned when accumulated sediments equal approximately one-half of trap storage ' capacity. Maintenance is the responsibility of the developer. ' 6. REFERENCES ' 1. City of Fort Collins, "Storm Drainage Design Criteria and Construction Standards" (SDDCCS), May 1984. ' 2. Soil Survey of Larimer County Area, Colorado. United States Department of Agriculture Soil Conservation Service and Forest Service, 1980. 1 3. Urban Drainage and Flood Control District, "Urban Storm Drainage, Criteria Manual", Volumes 1 and 2; dated June 2001, and Volume 3, dated September 1992. 4. City of Fort Collins Municipal Code and Charter, Chapter 10, "Flood Prevention and Protection'. ' 5. "Preliminary/Master Drainage Study for Woodridge", RBD, Inc. Engineering Consultants, December 2; 1991. ' 6. "Final Drainage and Erosion Control Study for the Overlook at Woodridge Fourth Filing, Phase One" RBD, Inc. Engineering Consultants, June 14, 1995. Final Drainage and Erosion Control Report Page 10 ' Innovation Island September 6, 2006 I 1 I APPENDIX A MAPS AND FIGURES !N4P I,� I.�e IP0.0 E 'iLNll IIOIOIAI TU909 I1S9R.Alll FIRM FLOOD INSURANCE RATE MAP cm OP FORT COLLINS, COLORADO to im Comm MAP INDEX PANELS PRINTED: ]. S, A COMMUNITY -PANEL NUMBERS 080102 0001.0007 MAP BERSEO: FEBRUARY 15, 1939 J I A-1 I I I -------------- ---- I IN Iq 12 gm I I I d @ � 0 0 w I I @ I 2P . IM {a IO �� ■�M � 2. 0 ■ E cq a � � I 05 z o � §� �0 2 00 f 0 . 0k � ■ B 2 f § 0%E U. a I2f z �f � §3/ . ■Er '� �� � 2=M a� @ Raip 0w �$. to f�0 0M0 ©= @ >CL $E� k§ t §� . .- k2k Jt J k#$ 3�} ■ _ 2 I » . Le ° ° tM • a b 0 ` � 2 Q a_£ f k IL . (� / A'3 Soil Survey of Larimer County Area, Colorado INNOVATION ISLAND Map Unit Legend Summary Larimer County Area, Colorado Map .. %�'7G: e ', z...` r iir��i 's�.�.l•,,•� i ql d'A4v'1h ��` 1. �:( q V'° r 11" .9 1 percent slopes 91 Renohill-Midway clay 0.4 9.0 loams, 3 to 15 percent slopes USDA Na R. Web Soil Survey 1.0 National Cooperative Soil Survey 9/282005 Page 3 of 3 A-y I I 1 1 r 1 1 I I I I 1� I 1; APPENDIX B HYDROLOGIC AND HYDRAULIC CALCULATIONS 1 I I 1 0 'J I I LOCATIC PROJECT COMPUT. DATE: RUNOFF COEFFICIENTS & % IMPERVIOUS Innovation Island 1029-025-00 IS BY: JZ 6/28/2006 Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria % Impervious from Urban Storm Drainage Criteria Manual Streets, parking lots (asphalt) Sidewalks (concrete) Roofs Lawns (flat <2%, sandy soil) Runoff % coefficient Impervious C 0.95 100 0.95 96 0.95 90 0.10 0 SUBI DESIG ASIN IATION TOTAL AREA (ac.) TOTAL AREA (sq.ft) ROOF AREA (sq.ft) PAVED AREA (sq.ft) SIDEWALK AREA (sq.ft) LANDSCAPE AREA I (sq.ft) RUNOFF COEFF. (C2) RUNOFF COEFF. (c100) % Impervious 3.73 162,695 USE COMMERCIAL "C"VALUE 0.85 1.00 85 Fy 1.72 75,090 USE COMMERCIAL "C"VALUE 0.85 1.00 85 0.56 24,391 USE COMMERCIAL "C"VALUE 0.85 1.00 85 0.21 9,310 3,777 0 1,280 4,253 0.56 0.70 50 A+8 C+D 6.23 271,486 0.85 1.00 65 d C coefficients & % Impervious are area weighted C=E(Ci Ai) /At Ci = runoff coefficient for specific area, Ai Ai = areas of surface with runoff coefficient of Ci n = number of different surfaces to consider At = total area over which C is applicable; the sum of all Ai's � � � $ � @ @ @ $ @ I $ € k 0 s B ,) ;z 2L) §k k§ .2 e c k� CO N LL 0 0 0 Rf) /j\ 7(, £0 C) 0 j�( cr � k k ) ( [ k ) 4� 2■ _ ;;© ; �, {� u 2N® § l §§J£/ 2 R: 2 fee - @§!q@ q� § �/{ �a� � � is ! =22 2 -F ( . rn(k § m ka�&i� fn § � m m § E klu Rm& n J\E „ 0 lz 0 Md §a§\ \ } \ w (/ \ \ S { & l [ � S'Z t i I 1 I I ' u 1 1 1 C 0 Y y 0 O .c L 1 N LL N z C W Z 00 fU o LL 90 m W m F U z 0 zzz¢ € A� U 0 0 a 0 Q o Y Q f C m m o m z ~ E LL o rn r m E v my O U LU n m m u 7 U + � a 3 c m o rl� n N O I fV IV O ul w o A n m o n z m w N o- G No S O O O O c C O W � 0 0 0 0 0 0 7 o _ N U' o d°m y ... w m 0 0y� 0 aOD 0 _0000 f0 N N N N O e � N O O N m m n n � m V J o S 8 0 � U U W > N m m N Q c0 m m 0 U m O O O O g w t � z_ F. n r h M o ¢m Q m U m rn z 0t m N In F m w 0 a N O O c t U r f J U / U 0 � + co all u n W ,U. 3 0 fA N O f3 -3 I i I [1 I RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 2-Yr Storm) LOCATION: Innovation Island PROJECT NO: 1029-026-00 COMPUTATIONS BY: 1Z DATE: 6/28/2006 2 yrstorm, CIF = 1.00 DIRECT RUNOFF CARRY OVER ITOTAL REMARKS Design Point Tributary Sub -basin A (ac) C Cf tc (min) i (In/hr) Q (2) (ds) from Design Point Q (2) (cis) Q(2)tot (cis) 1 A 3.73 0.85 15.0 1.86 5.91 5.91 2 B 1.72 0.85 13.9 1.93 2.83 2.83 c 0.56 0.85 11.7 2.09 0.99 0.99 D 0.21 0.56 5.0 2.85 0.34 0.34 3 A+B+C+D 1 6.23 1 0.85 15.0 1.86 9.86 9.86 Q=CfCIA Q = peak discharge (cfs) C = runoff coefficient Cf = frequency adjustment factor i = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16/99) A = drainage area (acres) I = 24.221 / (10+tcf' 1029flows 3-y j 1 1 1 1 1 1 i 1 1 RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 100-Yr Storm) LOCATION: Innovation Island PROJECT NO: 1029-026-00 COMPUTATIONS BY: JZ DATE: 6/28/2006 100 yr storm, Cf = 1.25 DIRECT RUNOFF CARRYOVER TOTAL REMARKS Des. Point Area Design. A (ec) C Cf tc (min) I (In/hr) Q (100) (ofs) from Design Point Q (100) WS) Q(100)tot (cfs) 1 A 3.73 1.00 13.8 6.77 25.28 25.3 2 B 1.72 1.00 8.9 8.13 14.02 14.0 ' C 0.56 1.00 5.0 9.95 5.57 5.6 3 A+B+C+D 6.23 1.00 11.9 7.23 45.09 1 1 45.1 1029f1ows Q=CIA Q = peak discharge (cfs) C = runoff coefficient I = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16/99) A = drainage area (acres) I = 84.6821 (10+ tc)0.187s 8 -5 �l i] I i I I� I I u I I I I SUMMARY DRAINAGE SUMMARY TABLE Design Point Tributary Sub -basin Area (ac) C (2) C (100) tc (2) (min) tc (100) (min) Q(2)tot (cfs) Q(100)tot (cfs) DRAINAGE STRUCTURE /REMARKS 1 A 3.73 0.85 1.00 15.0 13.8 5.91 25.3 WQ Pond 2 B 1.72 0.85 1.00 13.9 8.9 2.83 14.0 existing 15' T pe R C 0.56 0.85 1.00 11.7 5.0 0.99 5.6 4 D 0.21 0.56 0.00 1 5.0 0.0 1 0.34 1 - WQ PLD 3 A+B+C+D 6.23 0.85 1.00 15.0 11.9 1 9.88 1 45.1 lexisting 15' T pe R I 5-6 Worksheet for Min. Alley Capacity Flow Element Triangular Channel Friction Method: Manning Formula Solve For: Discharge Roughness Coefficient: 0.613- Channel Slope: 0.00800 Wit Normal Depth: 0.22 ft Left Side Slope: 50.00 11111 (H:V) Right Side Slope: 50.00 ft/ft (H:V) Discharge: 5.68 ft'i/s Flow Area 2.42 W Wetted Perimeter: 22.00 It Top Width: 22.00 ft Critical Depth: 0,24 ft Critical Slope: 0.00499 ftift Velocity: 2.35 ft/s Velocity Head: 0.09 ft Specific Energy: 0.31 ft Froude Number 1.25 Flow Type: Supercritical Downstream Depth: 0.00 ft Length: 0.00 ft Number Of Steps: 0 Upstream Depth: 0.00 It Profile Description: NIA Profile Headloss: 0.00 it Downstream Velocity: 000 Ws Upstream Velocity: 0.00 Ws Normal Depth: 0.22 ft Critical Depth: 0.24 it Channel Slope: 0.00800 Wit Critical Slope: 0.00499 Wit G CfJ CI C! OO cs viO ZOW ul�_ m� cui a 1- 0 m m m m ` W UN30 W C VJ C L W pj C� OMZgyo c.' m ,&E.. m a 0JJo7dLnmm(pJD� odd>3LL ;qq>o�' U W W W 1�y W rL 1LL ri (i i-i LLLL�N Qz zZ zZ zz W z a W W— lions- =__ z Z Z z z U U U 6-8 1 1 1 1 1 for Trapezoidal Channel - 1 Flow E ment: Trapezoidal Channel FrictionMethod: Manning Formula Solve For Discharge Roughn ss Coefficient: 0.045^ Channe Slope: 0.12000 tti t NormalDepth: 1.00 It Left Sidi 3 Slope: 4.00 fttft (H:V) Right Si Je Slope: 4.00 ft/ft (H:V) Bottom dth 3.00 It Results Dischar e: 58.37 ft'!s Flow Area: 7.00 ft' Wetted Derimeter 11.25 It Top Wk Ith: 11.00 It CriticalDepth: 1.35 It Critical lope: 0.03251 ft/ft Velocity: 8.34 ft/s Velocity Head: 1.08 It Specific Energy: 2.08 it Froude umber. 1.84 Flow T Supercritical :am Depth: 0.00 0.00 Of Steps: 0 . Upstream Depth: 0.00 ProfileDescription: NIA Headlo s: 0.00 Downstream Velocity: 0.00 Upstream Velocity: 0.00 Normal Depth: 1.00 CriticalDepth: 1.35 Channe I Slope: 0.12000 ft It ft/s ft!s ft It 1ttft 11 0 APPENDIX C DETENTION POND ANALYSIS 1 11 1 L r-, i L 1 1 1 1 1 1 1 LOCATION: PROJECT NO: COMPUTATIONS BY: DATE: 100 yr storm, Cf = RATIONAL METHOD PEAK RUNOFF (City of Fort Collins, 100-Yr Storm - OLD rainfall) Innovation Island 1029-026-00 JZ 9/29/2005 1.25 :UIKECT RUNOFF CARRY OVER REMARKS Tea . Point rea Des n. i9 ao min in/hr cfs m Design Point MTW cfs t cfs s .0 5.0 .00 39.60 A owe le release un er 010 resinresintall conciltions Q=CIA Q = peak discharge (cfs) C = runoff coefficient i = rainfall intensity (in/hr) from OLD City of Fort Collins OF curve A = drainage area (acres) 0 C-I 1 1 1 1 1 0L-D UTy of F09-T Cbu_(ti5 INTERPOLATED VALUES FOR 100 YEAR INTENSITIES Te Value 15.00 9 0 //-- 5.10 9.0 5.20 8.9 5.30 8.9 5.40 8.9 5.50 8.8 5.60 '8.8 5.70 8.7 5.80 8.7 5.90 8.7 6.00 8.6 6.10 8.6 6.20 8.6 6.30 8.5 6.40 8.5 6.50 8_5 6.70 8.4 8.4 6.80 8.4 6.90 8.3 7.00 8.3 7.10 8.2 7.20 8.2 7.30 8.2 7.40 8.1 7.50 8.1 7.60 8.1 7.70 8.0 7.80 8,0 7.90 8.0� 8.00 7.9 ' 8.10 7;9 8.20 7.8 8.30 ;r 7.8 8.40 7.8 .8.50 7.7 8.60 7.7 8.70 - -7, 7 8.80 •'7.6 8.90 7.6 9.00 7.6 9.10 7.5 9.20 7.5 9.30 7.5 9.40 7.4 9.50 7.4 9.60 7.3 9.70 7.3 9.80 7.3 9.90 7.2 10.00 7.2 C-2 DETENTION VOLUME CALCULATIONS Rational Volumetric (FAA) Method 100-Year Event LOCATION: Innovation Island PROJECT NO: 1029-026-00 COMPUTATIONS BY: J.Zung DATE: 9/25/2005 Equations: Area trib. to pond = 4.40 Developed flow = QD = CIA C (100) = 1.00 Vol. In = Vi = T C I A = T Qp Developed C A = 4.4 Vol. Out = Vo =K Qpo T Release rate, QPo = 39.6 storage = S = Vi - Vo K = 0.9 Rainfall intensity from City of Fort Collins IDF Curve with updated (3.67") rainfall acre acre - site only cfs (from fig 2.1) Storm Duration, T (min) Rainfall Intensity, I (in/hr) Qp (cfs) Vol. In VI (ft) Vol. Out Vo (ft) Storage S (ft) Storage S (ac-ft) 5 9.95 43.8 13134 10692 2442 0.06 10 7.77 34.2 20503 21384 -881 -0.02 20 5.62 24.7 29677 42768 -13091 -0.30 30 4.47 19.7 35389 64152 -28763 -0.66 40 3.74 16.5 39494 85536 46042 -1.06 50 3.23 14.2 42686 106920 -64234 -1.47 60 2.86 12.6 45298 128304 -83006 -1.91 70 2.57 11.3 47509. 149688 -102179 -2.35 80 2.34 10.3 49428 171072 -121644 -2.79 90 2.15 9.5 51125 192456 -141331 -3.24 100 1.99 8.8 52648 213840 -161192 -3.70 110 1.86 8.2 54031 235224 -181193 -4.16 120 1.75 7.7 55298 256608 -201310 -4.62 130 1.65 7.2 56468 277992 -221524 -5.09 140 1.56 6.9 57556 299376 -241820 -5.55 150 1.48 6.5 58573 320760 -262187 160 1.41 6.2 59529 342144 -282615 170 1.35 5.9 60432 363528 -303096 6.96 180 1.29 5.7 61286 384912 323626 -7.43 Storage Volume: 2442 ft3 0.06 acre-ft C-3 I 17 I 1 WATER QUALITY STRUCTURE DESIGN - EXTENDED DETETION BASIN & POROUS LANDSCAPE DETENTION 1 1 1 1 1 LDesign Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility II Sheet 1 of 3 Designer: J. ZUNG Company: INTERWEST CONSULTING GROUP Date: June 28, 2006 Project: INNOVATION ISLAND Location: HARMONY S TAFT HILL 1. Basin Storage Volume le = 85.00 A) Tributary Area's Imperviousness Ratio (1 = I, / 100) i = 0.85 B) Contributing Watershed Area (Area) Area= 3.90 acres -oaf-{ : C) Water Quality Capture Volume (WQCV) WQCV = 0.36 watershed inches (WQCV =1.0-(0.91' IJ-1.1911+0.78' 1)) D) Design Volume: Vol = (WQCV / 12)' Area' 1.2 Vol = 0.141 acre-feet 2. Outlet Works A) Outlet Type (Check One) x Orifice Plate Perforated Riser Pipe Other: B) Depth at Outlet Above Lowest Perforation (H) H = 5.30 feet C) Required Maximum Outlet Area per Row, (N) A. = 0.08 ,square inches D) Perforation Dimensions (enter one only): i) Circular Perforation Diameter OR D = 0,313 inches, OR ii) 2" Height Rectangular Perforation Width W = inches E) Number of Columns (no, See Table 6a-1 For Maximum) no = 1 number F) Actual Design Outlet Area per Row (k) k = - 0D8 square inches G) Number of Rows(nr) nr= '16 number H) Total Outlet Area (A,,) A, = 1.22 'square inches 3. Trash Rack A) Needed Open Area: At = 0.5' (Figure 7 Value)' kt A, _ - 45 square inches B) Type of Outlet Opening (Check One) X . <2" Diameter Round 2" High Rectangular C) For 2", or Smaller, Round Opening (Ref.: Figure 6a). _Other: 1) Width of Trash Rack and Concrete Opening (W.,,) from Table 6a-1 V710 = 3 Inches ii) Height of Trash. Rack Screen(Hra) Hra= 94. inches 10-1 6/27/2006, 1:17 PM 1029BMP Design Forms, EDB 1 1 1 1 1 1 1 1 Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility Sheet 2 of 3 Designer: J. ZUNG Company: INTERWEST CONSULTING GROUP Date: June 28, 2006 Project: INNOVATION ISLAND Location: HARMONY & TAFT HILL iii) Type of Screen (Based on Depth H), Describe if "Other" X S.S. #93 VEE Wire (US Filter) Other: iv) Screen Opening Slot Dimension, Describe if "Other" X - 0.139" (US Filter) Other: v) Spacing of Support Rod (O.C.) , 0.75i inches Type and Size of Support Rod (Ref.: Table 6a-2) #156 VEE 318 in. x 1.0 in. flat bar vi) Type and Size of Holding Frame (Ref.: Table 6a-2) D) For 2" High Rectangular Opening (Refer to Figure 6b). 1) Width of Rectangular Opening (W) W = inches it) Width of Perforated Plate Opening (W,,", = W * 12") Ww„c = inches iii) Width of Trashrack Opening(W,,,_; from Table 6b-1 W.'—,= inches iv) Height of Trash Rack Screen (Hrn) Hire = inches v) Type of Screen (based on depth H) (Describe if "Other") Klemp'" KPP Series Aluminum Other: vi) Cross -bar Spacing (Based on Table 6b-1, Klemp'" KPP - inches Grating). Describe if "Other Other: vii) Minimum Bearing Bar Size (Klerl Series, Table 6b-2) Based on depth of WQCV surcharge) 4. Detention Basin length to width ratio 2.00 (UW) 5 Pre -sedimentation Forebay Basin - Enter design values A) Volume (no less than 5% of Design Volume from 1D) acre-feet B) Surface Area acres C) Connector Pipe Diameter inches (Size to drain this volume in 5-minutes under inlet control) D) Paved/Hard Bottom and Sides yes/no 1029BMP Design Forms, EDB D-z 6127/2006, 1:17 PM 11 Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility Sheet 3 of 3 Designer: J. ZUNG Company: INTERWEST CONSULTING GROUP Date: June 28, 2006 Project: INNOVATION ISLAND Location: HARMONY & TAFT HILL 6. Two -Stage Design - See Figure EDB-1 A) Top Stage (Depth Dwo = 2' Minimum) Dwo = feet Storage= acre-feet B) Bottom Stage Depth (Des = 1.0' Minimum, 2.0' Maxirl Dss = feet Bottom Stage Storage (no less than 3%of Design Volume (0.004236321375 acre-feet.) Storage= acre-feet Surf. Area= acres C) Micro Pool (Minimum Depth = the Larger of Depth= 2.50 feet 0.5' Top Stage Depth or 2.5 Feet) Storage= acre-feet Surf. Area= acres D) Total Volume: Vol,,,=Storage from 5A+6A+6B Voll= acre -feel (Must be > Design Volume in 1 D, or 0.1412107125 acre-feet.) 7. Basin Side Slopes (Z. horizontal distance per unit vertical) Z = 4.00 (horizontal/vertical) Minimum Z = 4, Flatter Preferred 8. Dam Embankment Side Slopes (Z, horizontal distance) Z = 4.00 (horizontal/vertical) per unit vertical) Minimum Z = 3, Flatter Preferred 9. Vegetation (Check the method or describe "Other") Native Grass Irrigated Turf Grass x Other: WATER TOLERATE PLANTS Notes 1029BMP Design Forms, EDB 0-3 6/27/2006, 1:17 PM 1 i 1 1 1 WQCV - level SPILL ELEV Extended Detention Basin Stage/Storage Stage (ft) Surface Area W) Incremental Storage (ac-ft) Total Storage (ac-ft) 4935 0 4936 401 0.00 0.00 4937 822 0.01 0.02 4938 1298 0.02 0.04 4939 1921 0.04 0.08 494 33014 0.06 0.13 4940.3 3484 0.02 0.16 4940.8 WQ Volume Required = WQ Volume Provided = 0.14 ac-ft 0.16 ac-ft 1029detention o-y I i Detention Pond iEmergency Overflow Spillway Sizing LOCATION: INNOVATION ISLAND PROJECT NO: 1029-025-00 COMPUTATIONS BY: J.ZUNG i SUBMITTED BY: INTERWEST CONSULTING GROUP DATE: 6/28/2006 top of berm Equation for flow over a broad crested weir I Q = CLH32 AXspill elevation where C = weir coefficient = 2.6 L H = overflow height L = length of the weir The pond has a spill elevation equal to the maximum water surface elevation in the pond Design spillway with 0.5 ft flow depth, thus H = 0.5 ft Size the spillway assuming that the pond outlet is completely clogged. IPond 305 Q (100) = 41 cfs (peak flow into pond) Spill elev = 5140.30 ft = WQCV ELEVATION Min top of berm elev.= 5140.80 Weir length required: L = 44 ft Use L = 45 ft v = 1.69 ft/s Ili I 1 I [1 I spillway, 1029detention D'S STRUCTURAL BMP DETAILS DRAINAGE CRITERIA MANUAL (V. 3) Table 6a4—Standardized WQCV Outlet Design Using Circular Openings (2' diameter maximum) Minimum Width (Wapen g) of Opening for a Well -Screen Type Trash Rack. Requires a minimurn water depth below the lowest perforation of 2'4". See Figure 6-a for Explanation of Terms. Maximum Dia. of Width of Trash Rack Opening (W..,.) Per Column of Holes as a Function of Water Depth H Below Lowest Perforation Circular Opening (inches) H=2.0' H=3.0' H�.O' H=5.0' H�.0' Maximum Number of Columns < 0.25 3 in. 3 in. 3 in. 3 in. 3 in. 14 < 0.50 3 in. 3 in. 3 in. 3 in. 3 in. 14 < 0.75 3 in. 6 in. 6 in. 6 in. 6 in. 7 < 1.00 6 in. 9 in. 9 in. 9 In. 9 in. 4 < 1.25 9 in. 12 in. 12 in. 12 in. 15 in. 2 < 1.50 12 in. 15 in. 18 in. 18 in. 18 in. 2 < 1.75 18 in. 21 in. 21 in. 24 in.. 24 in. 1 < 2.00 21 in. 24 in. 27 in. 30 in. 30 in. 1 Table 6a-2—Standardized WQCV Outlet Design Using Circular Openings (2' diameter maximum). US Filter*" Stainless Steel Well -Screen' (or equal) Trash Rack Design Specifications. Max. Width of Opening Screen #93 VEE Wire Slot Opening Support Rod Type Support Rod, On -Center, Spacing Total Screen Thiclutess Carbon Steel Frame Type 9' 0.139 #156 VEE 2/40 0.31' 3/8 x1.0'flat bar 18' 0.139 TE .07,Cx.50' 1' 0.655 '/V x 1.0 angle 24' 0.139 TE .074x.75" 1' 1.03' 1.0' x 1 W angle 27' 0.139 TE .074'x.75' . 1' 1.03' 1.0' x 1W angle 30' 0.139 TE .074'x1.0" 1' 1.155' 1'/; x 1W angle 36' 0.139 TE .074'x1.0' 1' 1.155" 1 1/4'x I W angle 42' 0.139 TE .105'x1.0' 1' 1.155' 1 '/4 x 1W angle u5 Filter, St. i,aui, Minnesota, uUn SD-10 n cv Rev. 12/28/2004 Urban Drainage and Flood Control District ID-6 1 1 1 1 1 1 1 1 1 1 1 DRAINAGE CRITERIA MANUAL (V. 3) STRUCTURAL BMP DETAILS 8- 4'-0- 8- Boll Down or caxl8.75 American Standard Lock Down Structural Sled Channel. Trash Rack Attached By Welding _ Rock Swivel Hinge Tubular V v Trash Rack_ On 6 4- Centers 3or4 H 1r - Optional Varies Flaw Contrd 2'-0- U.S. Filter• Stainless C C Steel Perforated - Orifice Plate to Steel Well —Screen Flow Control < 6'-0- (or equal) Per Tables Plate C_ 6a-1, 6o-2 _ Micro Pad W.S. _1 3- Minimum Outlet Pipe 18`T C8xl&75 American Standard Structural- — 2'-4- Sled Channel Famed T - Ilnimum Into Concrete Bottom And Sides Of < C. Trash Rack Alloehed Attached By Intermittent Welds. 4- Section A —A From Figure 6, Circular Openings Only Wall —Screen Frame Attached To Channel By intermittent Welds — Sled Perforated Flow Central Plate W6 . 1 Flow Trash Rack Attached By Intermittent Welding All Around 6 Min. Section B—B — Plan View From Figure 6. Circular Openings Only Limits for this Standardized Design: 1. All outlet plate openings are circular. 2. Maximum diameter of opening = 2 inches. *U.S. Filter, St. Paul, Minnesota, USA Urban Drainage and Flood Contra[ District Drainage Criteria Manual (V.3) ns V3-0.0e1 D.lerean Stainless Steel Support Bare No. 93 Stainless Steel (U.S. FBter• or Equal) Wires ff Flow Fes— a.139- 0.090- Section C—C From Figure 6, Circular Openings Only R Value = (net open area)Agross rack area) = 0.60 Figure 6—a Suggested Stondordardized Trash Rack and Outlet Design For WOCV Outlets With Circular Openings rlgure o-a—suggested Standardized Trash Rack and Outlet Design for WQGV Outlets With Circular Openings. Rev. 12/28/2004 Urban Dn>t "e and Flood Control Dfstrld SD-9 11 ISTRUCTURAL BMP DETAILS I 11 I I I I LIB I I I I I DRAINAGE CRITERIA MANUAL (V. 3) Note: Vertical WQCV Trash Rocks are shown in Figures 6, 6-o, and 6-b for suggested standardized outlet design. Adverse -Slope Trash Rack design may be used for non -standardized designs, but must meet minimum design criteria. Structural Steel Channel Stainless Steel Baits Formed Into Concrete.- WC_-E__ or Intemnittant Weida, See Figures 6-a. 6-b A See Figures 6-a, 6-b H Varies 2'-0' to W-0, C B C C 2'- um) kf A WQCV Trash Rocks. Elevation 1 Well -screen trash rocks shall be stainless steel and shall be attached by intermittant welds along the edge of the mounting frame. 2. Bar grate trash racks shall be aluminum and shall be bolted using stainless steel hardware. 36 Trash Rock widths are for specified trash rack material. Finer well -screen or mesh size than specified Is acceptable, however, trash rack dimensions need to be adjusted for materials having a different open area/gross area ratio (R value) 4. Structural design of trash rack shall be based on full hydrostatic head with zero head downstream of the rack. Overflow Trash Racks: 1. All trash racks shall be mounted using stainless steel hardware and provided with hinged and lockable or boltable access panels. 2. Trash rocks shall be stainless steel, aluminum, or steel. Steel trash racks shall be hot dip galvanized and may be hot powder pointed after galvanizing. 3. Trash Rocks shall be designed such that the diagonal dimension of each opening is smaller than the diameter of the outlet pipe. 4. Structural design of trash rack shall be based on full hydrostatic head with zero head downstream of the rack. Urban Drainage and Figure 6 Flood Control District Suggested WQCV Outlet Standardized Drainage Criteria Manual (V.3) Trash Rack Design Fir. V3-0ullet Detqf&d-g (minim 11"9111111's 1151--bugg0steu VVQUV outlets Standardized Trash Rack Design. I SD-8 Rev. 12/2&2004 Urban Drainage andFk)od Contral Distirld 1 1 1 1 1 1 1 1 1 1 1 1 1 DRAINAGE CRITERIA MANUAL (V. 3) 0.50 0.45 0.40 0.35 s 0.30 8 0.25 a 0.20 3° 0.15 0.10 0.05 0.00 0 I I I 8-hr drain time a - 0.7 12-hr drain time a - 0.8 24-hr drain time a - 0.8 40-hr drain time a -1.0 wocv--a,yo.:au STRUCTURAL BEST MANAGEMENT PRACTICES Bctended Detention Basin 40-hour Drain Time Retention Pond, Porous Revement Detention and Porous Landscape Detention 12-hour Drain Time 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Total Imperviousness Ratio (1=1./100) FigurePLD-2 Water Quality Capture Volume (WQCV), 800' Percentile Runoff Event 10-2005 Urban Drainage and Flood Control District S-63 T)- 4 0 :1 . I FT 2 FLOW INTO INLET PER S.Q. FT. OF OPEN AREA (CFS/ Figure &3 CAPACITY OF GRATED. INLET IN SUMP (From: Wright I -McLauphlin Engineeit.. 1969) 0vf4floLA,) bang y- 40VI 0, ':7 MAY 1984 5-11 0E5IGN CRITERIA 6V- 1 1 1 1 1 II Circular Pipe Flow II Project: INNOVATION ISLAND Pipe ID: OUTLET TO EXTENDED DETENTION BASIN D Pipe Invert Slope So = 0.0100 ft/ft Pipe Manning's n-value n = 0.0130 Pipe Diameter D = 18.00 inches Design discharge Q= 10.0 cfs flow area Af = 1.77 sq it flow wetted perimeter Pf = ' 4.71 ft Central Angle Theta = 3.14 rad -flow capacity Qf — cis :ulation of Normal Flow Condition Central angle (0<Theta<3.14) Theta = ' 2.16 red area An = 1.47 sq it ad perimeter Pn = 3.24 it depth Yn = 1.17 it velocity Vn = 6.78 fps harge Qn "1,0:011cfs Central Angle (0<Theta-c<3.14) Theta-c = 2.25 red ;al flow area Ad = 1.54 sq ft ;al top width Tc = 1.17 it ;al flow depth Yc = - 1.22 it ;al flow velocity Vc = " -.6.50 fps ide number Fr 2<_-,: E` t00 UD-Culvert_EDB, Pipe 0-0 6/27/2006, 1:51 PM Designer: Jennifer Zung Design Procedure Form: Porous Landscape Detention (PLD) ' J Company: Interwest Consulting Group ' Date: June 28, 2006 Project: Innovation Island - BASIN D Location: _Harmony & Taft Hill 1. Basin Storage Volume ( I, = 100% if all paved and roofed areas u/s of PLD) I, = 50.00 % A) Tributary Area's Imperviousness Ratio (i = h / 100 ) i = 0.50 - B) Contributing Watershed Area Including the PLD (Area) Area = 9,310 square feet C) Water Quality Capture Volume (WQCV) WQCV = 0.17 watershed inches (WQCV = 0.8' (0.91 ' I' - 1.19' I`+0.78' I)) D) Design Volume: Vol, = (WQCV / 12)' Area Vol = 128.0 cubic feet 2. PLD Surface Area (Apio) and Average Depth (d„) Apcn = 230 square feet (d,,,: _ (Vol / A,$), Min=0.5', Max=1.0') d_ _ 0.56 feet 3. Sand/Peat Mix and Gravel Subbase (See Figure PLD-1) A) 67 % Sand / 33 % Peat Mix with 8" ASSHTO a67 Coarse X 18" minimum depth sand/peat mix with Aggregate subbase underdrain unless in sandy soils (no underdrain rec.) B) 67% Sand / 33% Peat Mix with no aggregate subbase 36" minimum depth sand/peat mix for NRCS Type D soils where underdrain is not possible C) Other Other'. 5. Draining of PLD (Check A, or B, or C, answer D) - Infiltration to Subgrade with Permeable Based on answers to 5A through 5D, check the appropriate method Membrane: 5(C) checked and 5(D) = no A) Check box if subgrade is heavy or expansive clay : Underdrain with Impermeable B) Check box if subgrade is silty or clayey sands X Membrane: 5(A) checked or 5(D) = yes C) Check box if subgrade is well -draining soils X Underdrain with Permeable Membrane: D) Does tributary catchment contain land uses that may have 5(B) checked and 5(D) = no petroleum products, greases, or other chemicals present, such as gas station, yes No Underdrain with Impermeable Membrane: No hardware store, restaurant, etc.? I xo 3(B) checked - Evapotranspiration only Other'. Notes: ' o- Iz 1029BMP Desiqn Forms, PLD 6/27/2006, 1:17 PM 1 1 1 1 STRUCTURAL BEST MANAGEMENT PRACTICES DRAINAGE CRITERIA MANUAL (V. 3) All side slopes at 3:1 or flatter Optional 10 unless vertical wall Is used. or 100 Year Detention /Ifffgat*dTurf Grass, Drylend Greases, and Wrap all p Slotted Curb WOCV other Plantings P gectextlle fabrics u Witter to top of soft. Attach firmly to r-PAVEME � Surface i I wells of bench sides. 5" min,12" max average depth _,..3 ______ f 'R r is. SandlPeat layer V-shaped Concrete Rundown See Section A A 16mf1 Impermeable • --,' Liner If on expansive or Type D soils, otherwise use gectextlIs 1 3 4anldia w/ 60 to S0 Parfo ed Pipe openings/inch Underdmin connected to Inlet(may be eliminated If underlaying soils are sandy)* b MIN Ltl;" ..� Ar �. � �:� ••e'. •N SECTIONA-A S-62 8" Gravel Layer •� —" —' (CDOT STEC 703, AASHTO Optional 10 or #67or#4 Coarse 100-year' Aggregate) Detention Control Orfte Nonwoven Geotextile Fabric ASTM D4751- ADS U.S. STD. Sieve #40 to iW ASTM D4632-MIN. Grab Strength 120lbs When the underlying soils are NRCS Type D or expansive soils, or when landu uses pose a potential for groundwater contamination, use Impermeable liner under and on sides of basin. .. (1) Wtien Type A or B soils Q.e., well draining) are present under the PLD and Infiltration is allowed, eliminate the S" gravel layer and the underdraln. (2) When Type D soils are present or when Infiltration Is not allowed and underdmins are not feasible, replace the 6" gravel layer with 1S" layer of sand -peat mix (or, sand and Class A compost mix), eliminate underddrein and underline with impermeable membrane. Figure PLD-1— Porous Landscape Detention — Typical Sections 10-2005 Urban Drainage and Flood Control District y Geotechnical Engineering Report llerramn Habitat for Humanity — Innovation Island S/E/C of Harmony Road and Taft Hill Road ' Fort Collins; Colorado Project No. 20055152 ' System described in Appendix C. Samples of bedrock were classed in accordance with general notes for Bedrock Classification.. At that time, the field descriptions were confirmed or modified as necessary and an applicable laboratory testing program was formulated to determine engineering properties of the ' subsurface materials. Boring logs were prepared and are presented in Appendix A. Laboratory tests were conducted on selected soil and bedrock samples. The test results were used for ' the geotechnical engineering analyses, and the development of foundation and earthwork recommendations. All laboratory tests were performed in general accordance with the applicable ASTM, local or other accepted standards. ' Selected soil samples were tested for the following engineering properties: ' Water Content . Plasticity Index • Dry Density • Grain -Size Distribution ' Swell -Consolidation SITE CONDITIONS The site for the proposed townhome and commercial/retail development is situated near the southeast comer of Harmony Road and Taft Hill Road in southwest Fort Collins, Colorado. Directly at the southeast corner of the intersection along the northwestern portion of the site is an existing Fort Collins - Loveland Water District pump station, with a chain fence enclosure. This property is not included within the Innovation Island Parcel. The proposed development site is sparsely vegetated with grass and weeds, is relatively flat, exhibiting positive surface drainage in the south to east directions and exhibits an approximate 8.to 10-feet of relief across the site from the northwest portion to the southeast portion. ' Harmony Road meanders along the northern and eastern boundaries, Taft Hill Road borders along the west, and the existing Overlook Residential Development is located to the south. ' SUBSURFACE CONDITIONS ' Soil and Bedrock Conditions The subsurface soil conditions encountered on the site consisted of an approximate 2 to 3-foot layer of overlot grading sandy lean clay fill material underlain by the native cohesive soils. The native �( sandy lean clay an c a e n s ra a was encountered beneath the surface fill material and extended to the coarse granular soils or weathered bedrock stratum below. Silty sand with gravel ' was encountered in eight (8) of the nine (9) test borings at approximate depths o to 12-feet below Ail site grades and extended to the depths explored or to the underlying bedrock. Siltstone/claystone Bedrock was encountered in Test Boring Nos. 4 through 8 at approximate depths of 11 to 12-feet 3 I I n I ' APPENDIX E ' EROSION CONTROL AND SURETY CALCULATIONS 11 1 17 EFFECTIVENESS CALCULATIONS PROJECT: INNOVATION ISLAND STANDARD FORM B COMPLETED BY: JZ DATE: 27-Jun-06 EROSION CONTROL C-FACTOR P-FACTOR METHOD VALUE VALUE COMMENT BARE SOIL 1.00 1.00 SMOOTH CONDITION ROUGHENED GROUND 1.00 0.90 ROADSIWALKS 0.01 1.00 GRAVEL FILTERS 1.00 0.80 PLACED AT INLETS SILT FENCE 1.00 0.50 SEDIMENT TRAP 1.00 0.50 STRAW MULCH (S = 1-5%) 0.06 1.00 FROM TABLE 8B WATTLES 1.00 0.80 EFF = (1-C*P)*100 MAJOR SUB BASIN AREA EROSION CONTROL METHODS BASIN BASIN (Ac) A 3.73 ROADS/WALKS 0.93 Ac. ROUGHENED GR. 0.60 Ac. STRAW/MULCH 2.20 Ac. WATTLES, SILT FENCE NET C-FACTOR 0.20 NET P-FACTOR 0.39 EFF = (1-C*P)* 100 = 92.2% B 1.72 ROADS/WALKS 0.67 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.85 Ac. SILT FENCE, GRAVEL FILTERS NET C-FACTOR 0.03 NET P-FACTOR 0.35 EFF = (1-C*P)*100 = 98.8% C 0.56 ROADS/WALKS 0.22 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.34 Ac. SILT FENCE NET C-FACTOR 0.04 NET P-FACTOR 0.50 EFF = (1-C*P)* 100 = 98.0% D 0.21 ROADS/WALKS 0.03 Ac. ROUGHENED GR. 0.08 Ac. STRAW/MULCH 0.11 Ac. NET C-FACTOR 0.39 NET P-FACTOR 0.96 EFF = (I-C*P)* 100 = 62.1 % TOTAL AREA = 6.23 ac TOTAL EFF = 93.5% (P (basin area * eTf) / total area REQUIRED PS = 80.8% Since 93.5% > 80.8%, the proposed plan is o.k. 1029EROSION E-1 CONSTRUCTION SEQUENCE ' Project: INNOVATION ISLAND Date: AUGUST 9, 2006 Indicate with bar line when constructions will occurr and when BMP's will be installed/removed in relation to the construction Dhase 1 1 1 CONSTRUCTION PHASE (2007) JAN FEB MAR APR MAY JUN JUL AUG SEPT OCT NOV DEC Grading (Include Offsite) Overlot Detention/WQ Ponds Swales, Drainageways, Streams Ditches Pipeline Installation (Include Ofislte) Water Sanitary Sewer Stormwater Concrete Installation (Include Otrsite) Area Inlets Curb Inlets Pond Outlet Structures Curb and Gutter Box Culverts, Bridges Street Installation (Include Offsite) Gradiing/Base Pavement Miscellaneous (Include Offsite) Drop Structures Other (List) BEST MANAGEMENT PRACTICES Structural Silt Fence Barriers Contour Furrows (Ripping/Disking) Sediment Trap/Filter Vehicle Tracking Pads Flow Barriers (Bales, Wattles, Etc) Inlet Filter Sand Bags Bare Soil Preparation Terracing Stream Flow Diversion Rip Rap Erosion Control Matting Vegetative Temporary Seed Planting Mulching/Sealant Permanent Seed Planting Sod Installation N etti ngs/Blankets/Mats Other (List) 1 INNOVATION ISLAND EROSION CONTROL COST ESTIMATE JOB NO. 1021-019-00 EROSION CONTROL MF.ASIIRES COMPLETED BY: JPZ ITEM DESCRIPTION I UNITS I UNIT COST lQUANTITY I TOTAL COST 1 TEMPORARY SEED & MULCH ACRE $ 775.00 3.5 $ 2,710.04 2 SILT FENCE LF $ 3.00 1,393 $ 4,179.78 3 GRAVEL CONSTRUCTION ENTRANCE EACH $ 500.00 1 $ 500.00 4 INLET PROTECTION EACH $ 250.00 3 $ 750.00 5 STRAW WATTLES EACH $ 200.00 3 $ 600.00 6 SEDIMENT TRAP EACH $ 500.00 1 $ 500.00 COST $ 9,239.82 CITY RESEEDING COST FOR TOTAL SITE AREA ITEM DESCRIPTION UNITS I UNIT COST IQUANTITY I TOTAL COST 1 RESEED/MULCH ACRE 1 $ 775.00 1 6.2 1 $ 4,830.16 COST $ 4,830.16 SECURITY DEPOSIT $ 9,239.82 REQUIRED EROSION CONTROL SECURITY DEPOSIT WITH FACTOR OF 150% $ 13,859.73 E-3 I I I a- on Q G 0 I C) I -C, -c- 'Ln Lo Ln I Lo v co co co I I I C I all 01) cn M;= c co cc co co, I =mm m (T m C) C71 c" m C) cl CD CD -cr -cl V:t -Z.- Ic, mr c cc -cl Ln Ln LO Ma co 00 I CD I r, cc co cr. 01 C1 cn aw (71 m m C'% C71 a.- C.) m m m aN 1 CV co co =.CoCW'WWWcgWWWC?WWCC M. .C:- Ln Lo Lo %0: Lo r- r` r-_ r\ r, r .. r�. r'_ r., f✓ r-, Co Co CC,= Co . . . . . . . . .. -tr c -c- c c v e c -0- mr co m co co q -co w CO m ,co co OI 1= N. en Ln Ln LI) tmo %-0 lo lD %0 '.0 r, r-, i-- r-, r� i-- i` C'. 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N L'i C%j CIJ C-4 = cc cc co co co C: Co. co �co co = co co co co co co co co co co = co cc co C:) a I LL- I Ln 1. Ln Ln CTN m --d- Ln Lm F` r-- t� CIO W co m m 0) m C1 cn,c OO.00C W I C%j I M 4= j= 4 CV CV CJ CIJ Cl- I m m W W M w W W m m co co, co co co CO CO = = = CO CO C) I -cz- Lo C:'� m Ln %.c m cn,CD CCD '-4 CV m m m cn m . I . . . . . i . . . . . . . . . .. . . . . cli I co c7l O C) C) O C C:) C) I to I un P, r,. W m m C7 A 4 m m m m to, CS co m m cn cm 0 m m a) CD 0 C) C•OC7000Oca) CD CD cm t,, co co co co 00 cc cO 00 CO 00 00 00 CO CO. 00 I CD I to r-) C) c n cn C C-i m cn mt- -z,-,Ln Ln Lo Ln ID %D '�DAD r'- t-D kc %0 n r, r� co co, cc co ca co co co co co co co m w WCOWW w Ln I m CD c La I-. r" r-. r, %.o ko Ln m m Cm vD C� CIQ C�i . . . . . . . . . . . . . . . CV C'j C%j N c%j N eq . . . 0 CD .:Ec CD C) C 0c) OCD 00 0 CD CD CD c) C) c= c) CD cl c) CD I a) CD C CD = O CD C) i0 Cl c:' C:> 40 CD CD CD C) CD CD C) CD Cp O. 0 CI— C) = I -=- Ln LC I-, W. cn �'C%j m -tr Ln Lo r-- C* C� C),Lr. C:) tn a Ln C�' U- LU m C cr Ln __j PACE. 23 Is TABLE 5.1 F-,q 1 1 1 1 RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: INNOVATION ISLAND STANDARD FORM A COMPLETED BY: JZ DATE: 27-Jun-06 DEVELOPED ERODIBILITY Asb Lsb Ssb AI a LI At a S1 Lb Sb PS SUBBASIN(s) ZONE (AC) (FI) 'A) (FT) (%) (e/) A MODERATE 3.73 905 1.1 3380 4.0 B 1.72 700 2.0 1207 3.4 c 0.56 300 1.5 168 0.8 D 0.21 20 2.0 4 0.4 Tom] 6.23 4759 8.7 764 1.4 80.8% Asb = Sub -basin area Lsb = Sub -basin flow path length Ssb = Sub -basin slope Lb = Average flow path length = sum(Ai Li)/sum(Ai) Sb = Average slope = sum(Ai Si)/Sum (Ai) PS is taken from Table 8-a (Table 5.1, Erosion Control Reference Manual) by interpolation. An Erosion Control Plan will be developed to contain PS% of the rainfall sedimentation that would normally flow off a bare ground site during a 10-year, or less, precipitation event. Erosion.xls V = Area (acres) x 100 cy/acre Area = 6.23 acres V = 623 cy 16828 W 0.39 ac-ft r.5 APPENDIX F EXCERPTS FROM OTHER REPORTS I [1 1 I I 1 1' 1 - MAIL CREEK BASIN MASTER DRAINAGE PLAN 1 HYDROLOGY TECHNICAL APPENDIX 1 1 PREPARED FOR: City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80521 1 1 1 PREPARED BY: Sear -Brown ' 209 South Meldrum Fort Collins, CO 80521 1 1 April 22, 2002 1` 1 F-1 FINAL DRAINAGE AND EROSION CONTROL STUDY FOR THE OVERLOOK AT WOODRIDGE FOURTH FILING PHASE ONE FORT COLLINS, COLORADO June 14, 1995 Prepared for: Woodcraft Homes 3665 JFK Parkway Building 1, Suite 300 Fort Collins, Colorado 80525-3153 Prepared by: RBD, Inc. Engineering Consultants 209 South Meldrum Fort Collins, Colorado 80521 (303) 432-5922 RBD Job No. 434-011 F"u FINAL DRAINAGE AND EROSION CONTROL STUDY FOR THE OVERLOOK AT WOODRIDGE FOURTH FILING PHASE ONE FORT COLLINS, COLORADO `'■ I. GENERAL LOCATION AND DESCRIPTION ' A. Location ' The Overlook at Woodridge Fourth Filing P.U.D. is bounded by Taft Hill Road (County Road 19) on the west, Imperial Estates on the north, future Harmony Road and The Gates Fourth Filing to the east, and by the Overlook Third Filing ' on the south. The site location can also be described as situated in the Southwest 1/4 of Section 34, Township 7 North, Range 69 West of the 6th P.M., City of Fort Collins, Larimer County, Colorado:. The site location can be seen on Exhibit 1 in the Appendix.. B. Description of Property The Fourth Filing of the Overlook at Woodridge contains approximately 32.8 acres, more or less. Presently, the property is undeveloped. The property is being proposed for planned unit development within the City of Fort Collins Zoning District and will be developed consistent with the Overlook Fast through Third Filings at Woodridge. Native grasses presently cover the property. The topography of the site generally slopes from west to east at approximately 1.5 percent. II. DRAINAGE BASINS A. Major Basin Description ' The majority of the proposed development lies within Basin 80 (see SWMM portion of Appendix) of the McClellands and Mail Creek Major Drainageway Plan prepared by Cornell Consulting Company. A natural drainageway 1 uns from west to east along the southern edge of the project boundary within Basin 80. Runoff from Basin 80 is routed by open channels and culverts along the northern boundary of the Gates First, Second and Third Filings, along the north side of Seneca Street past Webber Junior High School, and then along the east side of _1 i= _ � Regency Drive to the existing Regional Detention Pond. This development will also include improvements to a portion of the existing Taft Hill Road, although these off -site improvements are not seeking Phase One approval. B. Sub -basin Description The Overlook Fourth Filing has been divided into 15 sub -basins. Fourteen (14) of these basins will drain to Basin 80 of the McClellands and Mail Creek Master Plan, while the- remaining Basin 0-2 drains into the historic Basin 77 of the McClellands and Mail Creek Master Plan. Except for the off-street portions of Basins 1 and 2A, all 15 basins will be developed consisting of proposed residential housing and street improvements, including improvements to Taft Hill Road and to Harmony Road. Basins 1 and 2A will be developed as neighborhood commercial sites at a later time. These sub -basins are shown on the ramage an Erosion Control Plan in the back pocket of this report. C. SWMM Revisions The portion of the City of Fort Collins' SWMM model for a 100-year storm event within the Mail Creek Basin --tributary to Seneca Street (conveyance element 24)--was updated to reflect field conditions, phasing, and proposed storm drainage - system modifications. Basins 75, 77 through 80, 86, 175, 176, 179, and 186 were added or updated to account for the presently developed Woodridge subdivisions (Overlook and Gates First through Third Filings) and the proposed Overlook Fourth Filing Phase One subdivision. Conveyance elements 23, 26, 31, 34, 37, 44, 47, 49, and 230 were also added or updated to be consistent with present and proposed conditions. III. DRAINAGE DESIGN CRITERIA A. Regulations The City of Fort Collins Storm Drainage Design Criteria is being used for the subject site. B. Development Criteria Reference and Constraints The 1990 Preliminary Drainage Report for Webber Junior High School states that the channel and culvert system along the north side of Seneca Street and the east side of Regency Drive was sized for undetained off -site 100 year developed runoff from Basins 79, 80, and 85. Recent SWMM analysis for Basins 79 and 80, by the City of Fort Collins, has determined that the existing channel, culverts and Seneca Street (downstream of the subject site) will receive greater 100-year 2 C / The proposed drainage, erosion control, and grading plans are included in the ' back pocket of this report. B. Specific Details The Overlook at Woodridge has been broken down into 15 sub -basins. The sub - basin designations correspond to the basin designations of the Preliminary/Master Drainage Study for the Woodridge development. Specific details of off -site basins will be addressed again in the final report for the entire Overlook Fourth Filing development. l� Runoff from sub -basins 1, 2A, 2B, 3A, 3B, 3C, 12, and 13 will be conveyed easterly towards Harmony Road by a combination of gutter flows and a storm ' drain system. At Harmony Road, developed runoff will be conveyed via storm drains within the Harmony Road alignment to the Woodridge regions c anne . Inlets at the low point of Harmony Road (D.P. t20 and D.P. 130) intercept the remaining street flow from the above basins, as well as remaining street flow from the Overlook and Gates Third Filings. The storm drains will daylight in the regional channel downstream of -the Harmony Road crossing. i To complete the storm drain design from the Overlook Third Filing Final Drainage and Erosion Control Study, a curb inlet will be constructed within the Third Filing at the northwest corner of the Harmony Road and Silvergate Road intersection. A curb inlet will be required. at this point (D.P. 11) as curb and gutter flows exceed City criteria. Third Filing storm drain flows will be piped from this inlet across Harmony Road to the regional channel. Runoff from sub -basins 4A, 4B, and 4C will be conveyed to the regional channel by a combination of gutter flows and a short storm drain system (using 21- and 30-inch pipe). This storm drain will daylight in the regional channel immediately upstream of the Harmony Road crossing (D.P.. 55). Runoff from sub -basins 5A, 5B, and 5C is primarily generated within the most upstream portion of the regional channel itself and flows eastward along the channel alignment. Runoff is combined with flows from sub -basins 4A, 4B, and 4C at D.P. 55. Storm water runoff collected in the regional channel will be directed easterly to the two existing 42-inch culverts immediately north of Seneca Street. From that point, flows travel via open channels and additional 42-inch culverts to the Regional Detention Pond at Wake Robin Lane and Regency Drive. Two swales along the south edge of the Overlook Fourth Filing site allow sidewalk access to the pedestrian walkway system within the regional drainage 4 O g $ g rn r ' o 1 e� 5gYqSFS U I - I cc 13 ri 9 sy gg •b4 Q x +qq1 � "1 gggg� O8 6 qq9 �f � W • r i � Y n ^ & pF ki 6§ Y6 y y�01 1;6, �F H ryYl �N Ff O O a $ � 53 HIS a ga j 5l as 94 s� 4 3 N Cl 3i3 v a u 9 n na F L an 8 p �p �9 RSSS Se' I r7_ 0 i F i � �• '8 q� "�� i s.• E •g F �� pp 9 h[Y $�ggRy �q� y g 8 gg • $��p� O£ g s s. A rL �? R R R R °R tp17 A 8 R R B A W A g�� F A a dod ea b c gg $8� at Rq4 R A R 6 IRS ddrn, b �� �.: R-R A:tA '& a 2 as a 'eat �aq�R w�Fi oy n am A �pA wA a .4 ri �p Ap ?SSS . � Ss'8QS F_a fz; - ----------------------------------------------=---------------------- ' UDINLET: INLET HYDARULICS AN& SIZING DEVELOPED BY DR. JAMES GUO, CIVIL ENG DEPT. U OF COLORADO AT DENVER SUPPORTED BY METRO DENVER CITIES/COUNTIES AND UD&FCD L,R ----------------------------------------------------- KEVIN GINGERY-RDB INC FT. COLLINS COLORADO..... ..-----......----------------- . ................ ON DATE 05-26-1994 AT TIME 12:18:27 t* PROJECT TITLE: Overlook 14 2-year *** CURB OPENING INLET HYDRAULICS AND SIZING: INLET ID NUMBER: 10 ' INLET HYDRAULICS: ON A GRADE. rpm QJGVlak Gil 0o6�r�4? 1�f 6rv� ' GIVEN INLET DESIGN INFORMATION: GIVEN CURB OPENING LENGTH (ft)= 15..00 ' REQUIRED CURB OPENING LENGTH (ft)= IDEAL CURB OPENNING EFFICIENCY = 16.78 0.98 ACTURAL CURB OPENNING EFFICIENCY = 0.95. STREET GEOMETRIES: STREET LONGITUDINAL SLOPE ($) = 0.60 1 STREET CROSS.SLOPE ($) STREET MANNING N 2.00 0.016 GUTTER DEPRESSION (inch)= 2.00 GUTTER WIDTH (ft) = 2.00 ' STREET FLOW HYDRAULICS: ' WATER SPREAD ON STREET (ft) = GUTTER FLOW DEPTH (ft) = 13.56 0.44 FLOW VELOCITY ON STREET (fps)= 2.53 FLOW CROSS SECTION. AREA (sq ft)= GRATE CLOGGING FACTOR ($)= 2.01 50.00 CURB OPENNING CLOGGING FACTOR($)= 10.00 INLET INTERCEPTION CAPACITY: ' IDEAL INTERCEPTION CAPACITY (of a)= 5.01 BY FAA HEC-12 METHOD: DESIGN FLOW (cfs)= 5.10—� FLOW INTERCEPTED (Cfs)= 4.83 ' CARRY-OVER FLOW (cfs)= 0.27 BY DENVER UDFCD METHOD: DESIGN FLOW (cfs)= 5.10 FLOW INTERCEPTED (cfs)= 4.51 -------------------------------CARRY- -- -- OVERFLOW(cfs)=------O -------------- UDINLET: INLET HYDARULICS AND SIZING ' DEVELOPED BY DR. JAMES GUO, CIVIL ENG DEPT. U OF COLORADO AT DENVER SUPPORTED BY METRO DENVER CITIES/COUNTIES AND UD&FCD ------------------------------------------------------------------------------ .MIN GINGERY-RDB INC FT. COLLINS COLORADO ............................. DATE 05-26-1994 AT TIME 12:18:59 *r PROJECT TITLE: Overlook 14 100-year L 1ti I i33 ' *** CURB OPENING INLET HYDRAULICS AND SIZING' INLET ID NUMBER: 10 ' INLET HYDRAULICS: ON A GRADE. 1 1] :1 GIVEN INLET DESIGN INFORMATION: GIVEN CURB OPENING LENGTH (ft)= REQUIRED CURB OPENING LENGTH (ft)= IDEAL CURB OPENNING EFFICIENCY = ACTURAL CURB OPENNING EFFICIENCY = STREET GEOMETRIES: STREET LONGITUDINAL SLOPE ($) STREET CROSS SLOPE M _ STREET MANNING N = GUTTER DEPRESSION (inch)= GUTTER WIDTH (ft) STREET FLOW HYDRAULICS: 15.00 36.06 0.62 0.57 0.60 2.00 0.016 2.00 2.06 WATER SPREAD ON STREET (ft) = 23.50 GUTTER FLOW DEPTH (ft) = 0.64 FLOW VELOCITY ON STREET (fps)= 3.40 FLOW CROSS SECTION AREA (sq ft)= 5.69 GRATE CLOGGING FACTOR ($)= 50.00 CURB OPENNING CLOGGING FACTOR(%)= 10.00 INLET INTERCEPTION CAPACITY: IDEAL INTERCEPTION CAPACITY (cfs)= 12.09 BY FAA HEC-12 METHOD: DESIGN FLOW (cfs)= FLOW INTERCEPTED (cfs)= CARRY-OVER FLOW (cfs)= BY DENVER UDFCD METHOD: DESIGN FLOW (cfs)= FLAW INTERCEPTED (cfs)= CARRY-OVER FLOW (cfs)= 19.50 11.12 8.38 19.50 10.88 8.62 ---------------------------------------------=-----=---------------------- UDINLET: INLET HYDARULICS AND"SITING DEVELOPED BY DR. JAMES GUO, CIVIL ENG DEPT. U OF COLORADO AT DENVER iSUPPORTED BY METRO DENVER CITIES/COUNTIES AND UD&FCD ---------- ---------------------------------------------------------------- iSER:KEVIN GINGERY-RDB INC FT. COLLINS COLORADO..** ........... TATE 05-26-1994 AT TIME 13:18:44 :** PROJECT TITLE: Overlook 14 2-year *** CURB OPENING INLET HYDRAULICS,AND SIZING: INLET ID NUMBER: 21 ' INLET HYDRAULICS: ON A GRADE. GIVEN INLET DESIGN INFORMATION: GIVEN CURB OPENING LENGTH (ft)= ' REQUIRED CURB OPENING LENGTH (ft)= IDEAL CURB OPENNING EFFICIENCY = ACTURAL CURB OPENNING EFFICIENCY = STREET GEOMETRIES: 15..00 �P,A01 25.52 I 0.80 0.74 STREET LONGITUDINAL SLOPE (t) = 0.60 STREET CROSS SLOPE M = 2.00 ' STREET MANNING N = 0..016 GUTTER DEPRESSION (inch)= 2.00 ' GUTTER WIDTH (ft) = 2.00 STREET FLOW HYDRAULICS: WATER SPREAD ON STREET (ft) = 18.44 GUTTER FLOW DEPTH (ft) = 0.54 FLOW VELOCITY ON STREET (fps)= 2.96 FLOW CROSS SECTION AREA (sq ft)= 3.57 GRATE CLOGGING FACTOR ($)= 50.00 CURB OPENNING CLOGGING FACTOR($)= 10.00 INLET INTERCEPTION CAPACITY: IDEAL INTERCEPTION CAPACITY (CfS)= 8.37 BY FAA HEC-12 METHOD: DESIFLOWINTERCEPTED(cfs)= 17.79 W CARRY-OVER FLAW (cfs)= 2.71 BY DENVER UDFCD METHOD: 0.50 FFLOWGI1 INTERCEPTED (Cfs)= 7.53 CARRY-OVER FLOW (cfs)= 2.97 is------------------------------------- �' UDINLET: INLET HYDARULICS AND SIZING DEVELOPED BY DR. JAMES GUO, CIVIL ENG DEPT. U OF COLORADO AT DENVER SUPPORTED BY METRO DENVER CITIES/COUNTIES AND UD&FCD LER•KEVIN GINGERY-RDB INC FT. COLLINS COLORADO................ I............. I)N DATE 05-26-1994 AT TIME 13:19:09 I** PROJECT TITLE: Overlook #4 100-year L 10 I I5/ ' *** CURB OPENING INLET HYDRAULICS AND SIZING: - INLET ID NUMBER: 21 ' INLET HYDRAULICS: ON A GRADE. GIVEN INLET DESIGN INFORMATION: GIVEN CURB OPENING LENGTH (ft)= REQUIRED CURB OPENING LENGTH (ft)= IDEAL CURB OPENNING EFFICIENCY = ACTURAL CURB OPENNING EFFICIENCY = ' STREET GEOMETRIES: t STREET LONGITUDINAL SLOPE M _ STREET CROSS SLOPE 0) _ STREET MANNING N = GUTTER DEPRESSION (inch)= GUTTER WIDTH (ft) _ STREET FLOW HYDRAULICS: 15.00 59.26 0.41 0.37 0.60 2.00 0.016 2.00 2.00 WATER SPREAD ON STREET (ft) = 33.63 GUTTER FLOW DEPTH (ft) - 0.84 FLOW VELOCITY ON STREET (fps)=, 4.24 FLOW CROSS SECTION AREA (sq ft)= 11.47 GRATE CLOGGING FACTOR ($)= 50.00 CURB OPENNING CLOGGING FACTOR(%)= 10.00 INLET INTERCEPTION CAPACITY: IDEAL INTERCEPTION CAPACITY (cfs)- 19.98 BY FAA HEC-12 METHOD: DESIGN FLOW (cfs)= FLOW INTERCEPTED (cfs)= CARRY-OVER FLOW (cfs)= BY DENVER UDFCD METHOD: DESIGN FLOW (cfs)= FLOW INTERCEPTED (cfs)= CARRY-OVER FLOW (cfs)= (00-vvl- 48.90 18.20 30.70 48.90 17.99 30.91 UDINLET: STREET FLOW ANALYSIS ------------------------------------------------------------------------ DEVELOPED BY OR JAMES GUO, CIVIL ENS DEPT, U OF COLORADO AT DENVER .SUPPORTED BY METRO DENVER CITIES/COUNTIES AUD 1DSFCD ....................................................................... SER:KEViN GINGERY-RDB INC FT. COLLINS COLORADO .............................. ATE 05-26-1994 AT TIME 13:37:39 STREET GUTTER HYDRAULICS ry 1 GIVEN GUTTER GEOMETRIES: LONGITUDINAL SLOPE (X) 0.60 1 CROSS SLOPE (X) ■ 2.00 DEPRESSION AT GUTTER (inch) ■ 2.00 GUTTER WIDTH (feet): 2.00 1 STREET MANNING ROUGHNESS N ■ 0,016 STREET UNDER THE GIVEN FLOW: PEAK RUNOFF FLOW RATE (cfs)= 0.60 1 FLOW CARRIED BY GUTTER (cfs)= 0.58 FLOW CARRIED BY STREET (cfs)■ 0.02 WATER SPREAD ON 'STREET (ft) = 3.71 1 GUTTER FLOW DEPTH (in) ■ 2.89 AVERAGE FLOW VELOCITY (fps)= 1.97 ------------------------------------------------------------------------------ 1 UDINLET: STREET FLOW ANALYSIS DEVELOPED BY OR JAMES GUO, CIVIL ERG DEPT, U OF COLORADO AT DENVER . SUPPORTED -BY METRO DENVER CITIES/COUNTIES AND IDSFCD R:KEVIN GINGERY-RDS INC FT. COLLINS COLORADO .............................. fATE 05-26-1994 AT TIME 13:37:52 f� STREET GUTTER HYDRAULICS l�Ipw GIVEN GUTTER GEOMETRIES: i LONGITUDINAL SLOPE (X) = 0.60 CROSS SLOPE M = 2.00 DEPRESSION AT GUTTER (inch)= 2.00 GUTTER WIDTH (feet)= 2.00 STREET MANNING ROUGHNESS N = 0.016 STREET UNDER THE GIVEN FLOW: kk PEAK RUNOFF FLOW RATE (eis)= 10.50 f 1 FLOW CARRIED BY GUTTER (cfs)= 3.59 FLOW CARRIED BY STREET (cfs)= 6.92 WATER SPREAD ON STREET (ft) = 18.41 GUTTER FLOW DEPTH (in) = 6.42 AVERAGE FLOW VELOCITY (fps)= 2.96 . f �1 V Irt6-6- --14Z( 6'aid L �-Wool rid5l- [1 I I 1 1 1 t 1 1 1 I CLIENT /W2� ' ` JOB NO. Eow PROJECT ( fir! o���,{���—CALCULATIONS FOR Engineering Consultants MADEBY�DATf�f( .L[ a„ED BY— DATE —SHEET OF No Text 1 1 1 ' 181 0 0 0 182 0 0 ' 80 C 9 41 31 86 l -D hN D 171 CONVEYANCE ECENENr 273 NODE 371 °E D C DIVERSION 7 mow NYDROORAPNS 81 82) (78 i L:1 85 90) (87 45 67 60 84 84 36 321 35 �a 7fi �A 69 ;181189 30 39 } 72 27 8 29 73 U 61 83 301^ 54 Ill 58 MAIL CREEK BASIN 1 µ -G�y w 41 iL44--::=J II yy m pb Iik I 1 • I/ I II I• I I � �,I II I II NOTES: 1. ALL DISTURBEO AREAS SHALL BE RESEEDED PERTHE LANDSCAPE PIANS �+�J!9stE a�3<y seaPAN ��'.��m =e tea_ Mtl fPRO 4l OPTIMUM oroxrw PROM .roPE-j A- PUNDRAIFD ANNE y ?a CgIC. PAN F 6 iC 1.0. 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