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HomeMy WebLinkAboutDrainage Reports - 08/08/1996FLIRT COO LLI�lr� UTULI rho � � , � � V IR Final Drainage Report for Stone Ridge P.U.D. Fourth Filing Phase II Fort Collins, Colorado April 30, 1996 Jol Final Drainage Report for Stone Ridge P.U.D. Fourth Filing Phase II Fort Collins, Colorado April 30, 1996 Prepared For: The Kaplan Company 1060 Sailors Reef Fort Collins, Colorado 80525 Prepared By: Northern Engineering Services, Inc. 420 South Howes, Suite 202 Fort Collins, Colorado, 80521 (970)221-4158 Fax (970)221-4159 Project Number: STO; 9613.00 Second Final Submittal 1 April 30, 1996 City of Fort Collins Stormwater Utility 235 Mathews ' Fort Collins, Colorado 80522 RE: Stone Ridge P.U.D. Fourth Filing, Phase II Fort Collins, Colorado Project Number: 9613.00 Dear Staff: Northern Engineering is pleased to re -submit this. Final Drainage Report for Stone Ridge P.U.D. Fourth Filing, Phase II for your review. We have addressed the comments contained on the Project Comment Sheet dated March 19, 1996 and have included in this report a written response for each comment. This report was prepared in compliance with technical criteria set forth in the City of Fort Collins Storm Drainage Design Criteria and Construction Standards manual. If you should have any questions or comments as you review this report, please feel free to contact me at your convenience. Sincerely, NORTHERN ENGINEERING SERVICES, INC. George A. tchock 1, ' Mary B. WohnradePuE; ;-- �� .�e 420 SOUTH H0W15; SUITE 202, FORT COLLINS, COLORADO 80521; (970) 221-4158, FAX (970) 221-4159 I I I 1 I 11 I LJ .1 1 11 Project Comment Sheet Response Form Project Description: Stone Ridge P.U.D. Fourth Filing, Phase II Project Number: STO; 9613.00 Project Engineer: Mary B. Wohnrade, P.E. Response Date: May 1, 1996 Comment Response Number 1. See Final Drainage Report, Pages 18-21 in Appendix 2. This culvert is shown on the RBD, Inc. Utility Plans for Stone Ridge Fourth Filing, Phase I and was sized as part of that project by RBD. Please refer to those plans and report. 3. Existing off -site grading is shown on plan Sheet 5/7. This off -site property is under the same ownership as the Phase II site, therefore no easement is required. 4. Silt fence shown on Sheet 5/7 and detail shown on Sheet 7/7. 5. Performance standard calculations are completed see Appendix of report. 6. Note has been added to cover sheet. 7. Red -lined Utility Plans have been reviewed. See additional comments on red -lined plans. re is reporting burden for this form is approximately 0.50 hrs (This estimate will vary from project ;ct). The burden time includes the time for reviewing the project comment sheet, gathering the neec and completing the response form. Send comments regarding the accuracy of the burden estim+ any suggestions for reducing this burden to: Northern Engineering Services, Inc., 420 South How 202, Fort Collins, Colorado 80525. r \ACP D\C"\%VJT t\IP.DYM. PROJECT LOCATION VICINITY MAP 1V / N.T.S. NORTHERN ENGINEERING SERVICES "" 420 SOMI HQM UUM 202. R. C0W 3. CDIORA°D BD3'<1 Sc<EE: N.r.S. STONE RIDGE P.U.D. FOURTH FILIN (910) 223-4I68 DFSILNER :YBW CNECFED B\: IAFJ Y `' DRAfrSYAN: PC<D PREFPFED:O]/1'/9F � SReele ' Final Drainage Report for Stone Ridge P.U.D. Fourth Filing, Phase II I. INTRODUCTION ' 1.1 Objective To provide a final drainage scheme for the proposed Stone Ridge planned unit ' development Fourth Filing, Phase II based on master drainageway planning and preliminary drainage concepts developed by others. Specific objectives as part of this study are: 1. To adopt the drainage and grading concepts contained in the Final Draina4e and Erosion Control Study for Stone Ridge P.U.D. ' Fourth Filing, Phase I, (Reference 1), 2. To consider the drainage schemes of adjacent Stone Ridge P.U.D. filings, 3. To consider any possible adverse effects downstream of the development due to developed stormwater, 1.2 Mapping and Surveying ' Field surrey information was provided by RBD, Inc. which included topographic mapping with a contour interval of -one (1) foot. ' 1.3 Site Reconnaissance A site visit was conducted on Monday February 26, 1996 by the project engineer. Based on the topographic mapping, existing drainage basins and land use ' were confirmed as well as existing adjacent structures. The location of existing swales and storm inlets were verified as well as their condition and flow direction. ' II. SITE LOCATION AND DESCRIPTION = ' 2.1 Site Location The project is located in the South Half of the Southeast Quarter of Section 29, Township 7 North, Range 68 West of the 6th Principal Meridian in Fort Collins, Colorado. The project is bounded by Horsetooth Road to the south and County Road 9 to the east. (See Vicinity Map). Adjacent developments include Stone Ridge P.U.D. Fourth Filing, Phase I to the north and south. ' Final Drainage Report Page 2 Stone Ridge Fourth Filing, Phase II ' 2.2 Site Description ' Stone Ridge P.U.D. Fourth Filing, Phase II is approximately 8.322 acres and has historically been furrowed agricultural land. The site has been previously overlot graded as part of previous Stone Ridge P.U.D. filings. The Fossil Creek Reservoir Inlet is located east of the site across County Road 9 and flows from northwest to southeast. ' 2.3 Irrigation Ditches and Reservoirs There are no irrigation laterals located on the Fourth Filing, Phase II site. ' III. HISTORIC DRAINAGE BASIN 3.1 Major Basin Description ' The site is located in the Foothills Basin (Basin G) and is included in the report entitled Foothills Basin (Basin G) Drainage Master Plan, by Resource Consultants, ' Inc., February, 1981. The master plan calls for an on -site detention facility for the Stone Ridge P.U.D. site which was designed by RBD Inc. and included in the report Stone Ridge P.U.D. Overall Site Detention Pond, March, 1994. The pond was ' constructed as part of Stone Ridge P.U.D. Third Filing and is intended to detain all developed stormwater within the Stone Ridge P.U.D.. ' 3.2 Historic Drainage Patterns The site has historically drained from west to east at a very gradual slope of approximately 0.5%. Off -site flows enter Phase II of the Fourth Filing from the west ' from Stone Ridge Fourth Filing, Phase I, Sub -Phase A. ' IV. DEVELOPED DRAINAGE BASIN 4.1 Developed Conditions The proposed development of the site includes: • extension of a private drive, • new water services and sanitary sewer, ' • and improvements to temporary swale #34. 4.2 Design Criteria and References Drainage criteria outlined in both the City of Fort Collins Storm Drainage Design ' Criteria Manual,(SDDCM) and Storm Drainage Criteria Manual by the Urban Drainage and Flood Control District have been referenced for this Final Drainage Study. ' Final Drainage Report Page 3 Stone Ridge Fourth Filing, Phase II ' 4.3 Hydrologic Criteria The Rational Method has been used to estimate peak stormwater runoff from ' the developed site. The initial 2-year and major 100-year design storms have been used in the evaluation of the proposed drainage system. Rainfall intensity data for the ' Rational Method has been taken from Figure 3-1 of SDDCM. 4.4 Hydraulic Criteria The City of Fort Collins Storm Drainage Design Criteria has been referenced for all hydraulic calculations. In addition, the following computer program has been utilized: • The computer program "Flowmaster" has been used to analyze the capacity of proposed Swale # 34. ' 4.5 Drainage Concept Drainage basins located on the Phase II site (Basins' 31-37) coincide with those delineated on the Final Drainage Plan by RBD, Inc. for Stone Ridge P.U.D. Fourth Filing, Phase I. Composite runoff coefficients and areas in all basins except Basin 34 have remained relatively unchanged from those calculated by RBD in the Final Drainage Report for the Fourth Filing, Phase I. Design Point 35 has been recalculated to reflect final runoff coefficients and design flows from Basin 34. Final design flows from Basin 34 are less than those ' estimated in the Phase I, Final Drainage Report for developed conditions (See pages 11 and 13, Appendix) therefore downstream conveyance elements will not require re- design. ' Developed stormwater from Stone Ridge Fourth Filing, Phase II will be conveyed overland in drive -over curb and gutter and in Swale #34 to existing open grass -lined swales (#33, #35, #36 and #38) and the overall site detention pond located in the northeast corner of the Stone Ridge P.U.D.. The existing temporary swale #34, ' which was constructed as part of the Fourth Filing, Phase I, will be improved and will contain an underdrain due to a proposed slope of 0.60%. Off -site stormwater from Phase I (Sub -Phase A) of the Fourth Filing will be conveyed through Phase II to the existing overall site detention pond via proposed Swale #34. ' Storm sewer will not be required as part of the Fourth Filing, Phase II improvements. ' Final Drainage Report Page 4 Stone Ridge Fourth Filing, Phase II ' V. EROSION CONTROL 5.1 Erosion Control Plan Permanent riprap will be provided at the proposed curb cut located at the upstream end of Swale #34. The improved temporary Swale #34 shall be seeded immediately upon completion with the permanent seed mix specified on the Grading Plan. Temporary sediment control consisting of straw bale dikes will be used in Swale #34 until permanent vegetation is established. A gravel filter will be required at the curb cut and silt fencing installed adjacent to all swales. VI. CONCLUSIONS ' 6.1 Compliance with Standards All drainage analyses have been performed according to the City of Fort Collins Storm Drainage Design Criteria Manual (SDDCM) and the Urban Drainage and Flood 1 Control District's Drainage Criteria Manual. Let me emphasize here, that many of the hydraulic calculations for downstream ' street and swale capacities have been completed in connection with previous filings of Stone Ridge P.U.D. by RBD, Inc.. These calculations are still valid because design flows for Phase 2 of the Fourth Filing are the same or less than those estimated by ' RBD for this phase. I would refer the reviewer to the report,'Final Drainage and Erosion Control Study for Stone Ridge P.U.D. Fourth Filing, Phase I for verification of downstream capacities, these do not require modification as part of Phase 2 due to consistent design flows. 1 1 1 1 1 1 Final Drainage Report Page 5 Stone Ridge Fourth Filing, Phase II REFERENCES 1. Final Drainage and Erosion Control Study for Stone Ridge P.U.D. Fourth Filing, Phase I, Fort Collins, Colorado, RBD, Inc. Engineering Consultants, March 3, 1995. 2. Foothills Basin (Basin G) Drainage Master Plan, Fort Collins, Colorado, Resource Consultants, Inc., February 1981. 3. Storm Drainage Design Criteria and Construction Standards, City of Fort Collins, Colorado, May, 1984. 4. Drainage Criteria Maunal, Urban Drainage and Flood Control District, Wright -McLaughlin Engineers, Denver, Colorado, March, 1969. Final Drainage Report Page 6 Stone Ridge Fourth Filing, Phase II APPENDIX PAGE Developed On -Site Hydrology .................................................. 1 - 8 Developed Hydrology Stone Ridge Fourth Filing, Phase I ....................................... 9 -13 Designof Swales....................................................................... 14-22 StreetCapacity....................................................................... 23-28 Design of Riprap Outlet Protection ....................................... 29-30 Erosion Control Calculations.................................................. 31-34 m DEVELOPED ON- SITE HYDROLOGY DEVELOPED HYDROLOGY Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO. File Number: DSNPT34.WQ1 15-Mar-96 Cale DESIGN POINT 34: (Includes Basin 34 TOTAL AREA = A (ac)= 4.100 RUNOFF COEFFICIENTS: (From Table 3-3) Impervoius Area/ Lot (ac)= 1.9400 C for Roofs = 0.95 Area of Streets and Walks(ac)= 1.1300 C for Concrete = 0.95 Area of Gravel Parking (ac)= 0.0000 C for Gravel = 0.50 Area of Lawn (ac)= 1.0300 C for Lawn = 0.25 COMPOSITE RUNOFF COEFFICIENT: C = 0.95(1.94+1.13)+0.25(1.03) = 0.77 4.1 Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years) Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years) OVERLAND FLOW: 1-2 = 1.87 (1.1 - CCf) SQRT(L) = 16.4 L (ft)= 150 CUBRT(S) S (%) = 20.8-17.8 = 2.00 T100 = 1.87 (1.1 - CCf) SQRT(L) = 15.5 150 CUBRT(S) C = 0.20 GUTTER FLOW: (To Sidewalk Culvert 34 L (ft)= 336 Tt = S(%)= 17.3-15.3= 0.60 336 V(fps) = 1.90 2-YEAR TIME OF CONCENTRATION; Tc2 = 19.3 min 100-YEAR TIME OF CONCENTRATION; TC100 = 18.4 min RAINFALL INTENSITY: FROM FIGURE 3-1: Q2(cfs) = CCf x i2 x A = Q100(cfs) = CCf x i100 x A = i2(in/hr)= 1.88 i100(in/hr)= 5.35. 6.0 < G. 48 o/< 21.2 < 25. /v oiL min min L = 2.9 min 60(V) DEVELOPED HYDROLOGY Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO. File Number: DSNPT34a.WQ1 15-Mar-96 Calc DESIGN POINT 34a: (Includes Basin 34a) TOTAL AREA = A (ac)= 2.180 RUNOFF COEFFICIENTS: (From Table 3-3) Impervious Area/ Lot(ac)= 1.1200 C for Roofs = 0.95 Area of Streets and Walks(ac)= 0.5900 C for Concrete = 0.95 Area of Gravel Parking (ac)= 0.0000 C for Gravel = 0.50 Area of Lawn (ac)= 0.4700 C for Lawn = 0.25 COMPOSITE RUNOFF COEFFICIENT: C = 0.95(1.12+.59)+0.25(.47) = 0.80 2.18 Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years) Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years) OVERLAND FLOW: T2 = 1.87 (1.1 - CCf) SQRT(L) = 16.4 min L (ft)= 150 CUBRT(S) S (%) = 20.8-17.8 = 2.00 T100 = 1.87 (1.1 - CCf) SQRT(L) = 15.5 min 150 CUBRT(S) C = 0.20 GUTTER FLOW: (To Sidewalk Culvert 34) L (ft)= 336 Tt = L = 2.9 min S (%) = 17.3 - 15.3 = .0.60 60(V) 336 V(fps) = 1.90 2-YEAR TIME OF CONCENTRATION; Tc2 = 100-YEAR TIME OF CONCENTRATION; T600 = RAINFALL INTENSITY: FROM FIGURE 3-1: i2(in/hr)= 1.88 Q2(cfs) = CCf x i2 x A = 3.3 QI00(cfs) = CCf x i100 x A = 11.6 19.3 min 18.4 min i100(in/hr)= 5.35 3/ DEVELOPED HYDROLOGY Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO. File Number: DSNPT34a.WQi 15-Mar-96 Calc DESIGN POINT 34b: (Includes Basin 34b) TOTAL AREA = A (ac)= 1.920 RUNOFF COEFFICIENTS: (From Table 3-3) Impervious Area/Lot (ac)= 0.8700 C for Roofs = 0.95 Area of Streets and Walks(ac)= 0.5500 C for Concrete = 0.95 Area of Gravel Parking (ac)= 0.0000 C for Gravel = 0.50 Area of Lawn (ac)= 0.5000 C for Lawn = 0.25 COMPOSITE RUNOFF COEFFICIENT: C = 0.95(.87+.55)+0.25(.50) = 0.77 1.92 Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years) Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years) OVERLAND FLOW: T2 = 1.87 (1.1 - CCf) SQRT(L) = 10.0 min L (ft)= 57.5 CUBRT(S) S (%) = 18.2-17.0 = 2.09 T100 = 1.87 (1.1 - CCf) SQRT(L) = 9.4 min 57.5 CUBRT(S) C = 0.20 GUTTER FLOW: (To Sidewalk Culvert 34 L (ft)= 318.5 Tt = S (%) = 16.65-15.3 = 0.42 318.5 V(fps) = 1.45 2-YEAR TIME OF CONCENTRATION; Tc2 = 100-YEAR TIME OF CONCENTRATION; Tc100 = RAINFALL INTENSITY: FROM FIGURE 3-1: 12(in/hr)= 2.20 Q2(cfs) = CCf x i2 x A = 3.2 QI00(cfs) = CCf x i100 x A = 11.7 13.6 min 13.1 min i100(in/hr)= 6.35 L = 3.7 min 60(V) 4/ DEVELOPED HYDROLOGY Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO. File Number: DSNPT35.WO1 DESIGN POINT 35: (Includes Basin 34 and 35 TOTAL AREA BASIN 34 = 4.100 TOTAL AREA BASIN 35 = 1.950 TOTAL AREA BASIN 34 AND 35= 6.050 RUNOFF COEFFICIENTS: C FOR BASIN 34 = 0.7700 C FOR BASIN 35 = 0.3300 (See Pg. 11, Appendix) COMPOSITE RUNOFF COEFFICIENT: 15-Mar-96 Calc C = 0.77(4.1)+0.33(1.95) = 0.63 6.05 Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years) Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years) BASIN 34 TIME OF CONCENTRATION: 2-YEAR TIME OF CONCENTRATION; Tc2= 19.3 min. 100 YEAR TIME OF CONCENTRATION; Tc100= 18.4 min. SWALE FLOW: (FROM DESIGN POINT 34 TO DESIGN POINT 35 L (ft)= 575 Tt = S(%)= 15.3-11.2= 0.71 575 V(fps) = 1.32 COMPOSITE TIME OF CONCENTRATION (BASIN 34 + BASIN 35) 2-YEAR TIME OF CONCENTRATION; Tc2 = 26.6 min 100-YEAR TIME OF CONCENTRATION; Tc100 = 25.7 min RAINFALL INTENSITY: FROM FIGURE 3-1: i2(in/hr)= 1.57 i100(in/hr)= 4.55 Q2(cfs) = CCf x i2 x A = 6.0 QI00(cfs) = CCf x i100 x A = 21.6 60(V) = 7.3 min ■■ ■■moon ■■ A -___-- ■■■■■■■■■■ ■■■■■1■■11o■■■I■■■■■■■■■■m■■■■ ■■■■■�■■■11■■m■nl,..mm�!!mm■■m■mm■mom ■■■■■■ill■m11■■■i�i■i■■■■■■■■■■■ mom= IImoEIII■■■■■■■■■■■■■■■■■■ ■■■■■m im°•mmmumim - ■■■■■■■ ■■■■omml■■1■111m!!m■■■■ ■■■■■■■ OMEN ■■■■■■moll ■■■■■■■■■■■■■■■■ ■■■mmom■m ■■■■■■■■■ ■■■■■■■mom■■■■m■■■■■■■■■■■■m momo■mm■mo■■■■■■■■■■mm■■m■■■ ■■■■■mm■■■■■■■■■■■■■■■■■■■■oom ■■�v ■■mom■■■■■■ ■■�v�� ■mm■■m■mm■■m■■■ OMEN m■■m■o■mmo■■■■■■■■■■■■■■■ ■■■■m■mo■■■■■■m■m■■■■■■■■■ MEN ■■mm■■■■■■■ MEN ■■■ MEN ■■ONE MEMO! mm■■■■■■■■■■■■■■■■o■■m ■■m■■mm■■■m SEEMS mmm■■m■■m■ ■■■■■mmm■■■m■■■■■■mm■mm■m■■■m mm■oo■■■■■■m■■■■■om■■■■■■■ m■m■■mm■■mmm OEM! ■mm■m■mmm■mmm m■m■■■■■■■■■■■■■ MIS m■m■■■MEN ■■■m■■mm■■■■■■ NONE ■■■■■■■■■■■■ ■■o■■m■ MEN■■■■■m■■m■mo■■m■■■m m w..m w m m!= m = = = m m= m TABLE 3- 3 RATIONAL METHOD RUNOFF COEFFICIENTS FOR COMPOSITE ANALYSIS (CITY OF FORT COLLINS, STORM DRAINAGE DESIGN CRITERIA .AND CONSTRUCTION STANDARDS) CHARACTER OF SURFACE RUNOFF COEFFICIENT STREETS, PARKING LOTS, DRIVES: ASPHALT —. _---------_._---- 0.95 CONCRETE _ --__-- ---------____-- 0.95 GRAVEL — -- — — — ------------- 0.50 ROOFS ---------------- — ----- ------ 0.95 LAWNS, SANDY SOIL: FLAT < 27 --_-- -- _-- _--- 0.10 AVERAGE 2 TO 7/— 0.15 STEEP > 7% _ 0.20 LAWNS, HEAVY SOIL: FLAT < 2% 0.20 AVERAGE 2 TO 7% 0.25 STEEP > 77 0.35 J:\ACAD\DET\TABLES.DWG NORTHERN ENGINEERING SERVICES "" " EAV: TABLE 3-3 420 SOUTH Howes SUITE 202. FT. COLLINS. CDLORADO eosz1 4,u,p;,,aw — �... RATIONAL KETHOD RUNOFF COEFFICIENTS 1 (9:ill JJ1-6150. ro.r......i. ..... o<re.rr............. ■it���������a���������■ ■�i��������������n���■ __-. � et_�=- No Text DEVELOPED HYDROLOGY STONE RIDGE FOURTH FILING, PHASE I Stoneridge PUD, Fourth Filing TPM Kaplan Co. 4-28-94 rev'd 2-28-95 This sheet calculates the, composite "C" values for the Rational Method. Design Area Imperviou "C" Pervic:ii "C" Ajotal ' A,imp ;ic. ac. Percent Im erv. Percent jPerviou Comp. "C" 31 0.95 0.2 1.1C8 0.736 66.4 33.6 0.70 32 0.95 0.2 1.243 0.4 32.2 67.8 0.44 33 0.95 0.2 2.563 0.835 32.6 67.4 0.44 34 0.95 0.2 4.099 2.42 59.0 41.0 0.64 35 0.95 0.2 1.945 0.334 17.2 82.8 0.33 36 0.95 _0.2 1.340 0.27 20.1 79.9 0.35 37 38 0.951 0.95 C.2 0.2r 4.750 1.715 219 0. �01 46.1, 5.91 53.9 94.1 0.55 0.24 39 0.95 0.2 1.379 0.'179 13.0 87.0 0.30 40 0.95 0.25 6.10c, i 2.539 41.6 58.4 0.54 41 0.95 6.25 6.990! 0.155 15.7 84.3 0.36 42 0.95 0.21 G.35C 0.186 53-11 46.9 0.60 43 0.95 0.21 1.1931 _ 0.955 80.1 19-91 0.80 44 0.95 0.21 0.903 0.101 11.2 88.8 0.28 STANDARD FORM £F-2 8-11-94 TIME OF CONCENTRATION Revised 2-28-95 STONERIDGE P.U.D. FOURTH FILING 2-YEAR DESIGN RUNOFF by: TPM bUD-basin uata Initial/Overland Travel Time, It Time, Ti Desig Area C Length S Ti Length I S I Vel Tt Basin ac. ft. % min. ft. I % I fps I min. 311 1.111 0.70 80 21 5.31 3101 0.6 1.41 3.7 321 1.241 0.44 170 2 12.8 50 0.6 1.4 0.3 331 2.56 0.44 1001 21 9.8 1130 0.5 1.1 17.1 34 4.10 0.64 80 21 6.1 410 0.5 1.5 4.6 35 1.95 0.33 105 2.3 11.2 430 0.5 1.1 6.5 36 1.34 0.35 307 2.5 18.11 0 0.5 2 0.0 37 4.751 0.55 120 2 8.91 670 0.71 1.6 7.0 38 1.721 0.24 170 2 16.6 225 2.5 2.4 1.6 39 1.38 0.30 110 3 10.9 645 3 2.8 3.8 40 6.11 0.54 300 12 7.9 0 0.5 0.0 0.0 41 0.99 0.36 34 25 2.8 680 0.5 1.3 8.7 42 0.35 0.60 40 2 4.7 290 3.6 2.8 1.7 43 1.19 0.80 28 2 2.4 1020 0.7 1.6 10.6 *34 4.1 0.26 80 2 11.2 410 0.6 1.2 5.7 44 0.9 0.28 110 3.5 10.6 240 4 3 1.3 Final Ti+Tt Tc min. Remarks " 9.0 13.4 26.9 10.7 17.7 18.1 15.9 18.2 14.7 7.9 11.5 6.4 13.0 16.8 Undevelo ed Flowpath 11.9 *Prior to the development of the future 4th Filing, Phase 2, undeveloped conditions will exist over a portion of Basin 34, and runoff will flow to temp. swale #34. ro 0 m N_ 0 Z 0 n Mm A D 41"'.2 /a.L n_ = /'-,rrA J,-__ /1.- 1 _ - - - - ., .I STORM DRAINAGE SYSTEM PRELIMINARY DESIGN DATA Wrip1 POYri g1 F, -t.�Sr'ayyy°U EU. Flaw Tine .� e : 51. �< ry OL Jr Od ,. 3m N¢ SIrM Poe St" Pb. Tat �,< inS UL 1 2 J 4 1 5 I 6 7 6 9 10 it 1 12 Ij lr 15 16 17 Ip 1 19 20 21 1 72 1 23 i. P. 31 " r7O2.� •II 2.0 r7-_t. ice,.: ,.. �. =��. o, i. i�r orficn.� W?C/� 0.& 5.3 "i /31n. = •'t 1.1l i+2=�.2-'ci-�. . 0.6 5. 7 7 90 0. 2.74 D.a4 0- a 9.r" 212-5-3 z7 0. I.55 3 <o•t 3.Z 0.4 , „ 111.7 1�,7M574 Tot -q l� l ii JJI �2 32 13.4 0. Z-U 1.80IT77 o.04 2 74 Lei i, a G,TT=c c 7. P. 33 8I ✓,P. �d 34 DEvt1L!7cpco�prn r Z4 O 1 <n,�InP- (/. .1GZ. p IOS D• P. 2�5 1 ZZ I 6.20 - v PO 33 0• G G, -4 Z tO..n 7 1,G- 3 dru_ Hsl Il mu+h v P. P 7 115.5 0.55 2.11 +' �r Are- e4 1 3 CJVlb.i_ a. 5. rtn. o 0.4 'L.7 >' ow V-rtr.M NE Pi rr 4 bw�,n3ll,- - 9. P. 525 E? 2 0.24 1.15 1.7Z 0.50 �5 33 s 3 21• 0.44 1 1.70 7SI 5.4A P. (e 9 0.4 1j9 .2-! o•S IS 0 3.02 2 1 W i 1n1-P,P- •' P Z) 7 I,n r - 0 51 ii4 5.?9 1-0 19, R.1 .r.i -3.4 F1.u1J ,a F1NaTv,. r... a '0,ter. P �{ -3 - 0.47 1.16 I. .(b 3. Ilo3 p / 3. MAX L-Yr- GtOiJ .- N-GjA/\Nl. 131 12.7 0.3o 2.13 I.'3 0. c-= 4"1. ?-- 1, = 4-2. 3..:.._ 40 1- 34 - 4004 42. 0. $ .1 LD. Z Ax 7- � ri.a.l Tn =-' aJ tl P. P. 41 44 11, 5 6. 3. Co Z.A100 Aga . P. 41 2 171 161.0 1,14 < �.✓S . , - _ l o. q 1 P. P• 37L. a 11,0Z7 AreA AZ 'PLA ?. U(37 AZ q.15 1' c'5 A PTt7 T-3 AP. 4 V- 4-47 LW 1,51 AWLa 4 -T np55 a" T Figure 5-1 LSC-`"" Form 11•3 TYPICAL FORM FOR STORM DRAINAGE SYSTEM PRELIMINARY DESIGN DATA \ (From: Wright -McLaughlin Engineers, 1969) rarw q4 STANDARD FORM SF-2 8-11-94 TIME OF CONCENTRATION revised 2-28-95 STONERIDGE P.U.D. FOURTH FILING 100-YEAR DESIGN RUNOFF by: TPM Sub -Basin Data Initia"Overiand Time, Ti Travel Time, Tt Final Ti+Tt Desig Basin Area ac. C Length ft. S. % Ti min. Length ft. S % Vel I fps Tt min. 3.7 Tc min. 6.7 Remarks 31 1.11 0.70 80 2 3.0 310 0.6 1.4 1.24 0.44 170 2 10.6 50 0.61 1.4 0.61 11.2 i32 33 2.56 0.44 100 2 8.21 1130 0.51 1.1 17.11 25.3 34 4.10 0.64 80 21 4.01 410 0.51 1.5 4.6 8.5 35 1.95 0.33. 105 2.31 10.0 430 0.5 1.1 0.5 16.5 36 1.34 0.35 307 2.51 16.0 0 0.51 2 0.0 16.0 37 4.75 0.55 120 21 6.7 670 0.71 1.6 7.01 13.7 37b 2.07 0.55 120 21 6.7 615 0.7 1.6 6.4 13.1 Flow in c8� to Inlet #36 38 1.72 0.25 170 21 15.21 225 2.51 2.4 1.0-1 16.8 for full channel length, L=360' 39 1.38 0.30 110 31 9.91 645 3 2.8 3.8 13.7 40 6.11 0.291 300 121 10.41 0 0.5 2.3 0.0 10.4 41 0.99 0.36 34 25 2.41 680 0.51 1.3 8.7 11.1 42 0.35 0.60 40 2 3.3 290 3.6 2.8 1.7 5.0 43 1.19 0.80 28 2 0.8 1020 0.7 1.6 10.6 11.4 *34 4.10 0.26 80 2 10.3 410 0.6 1.2 5.7 16.0 Undeveloped Flowpath 44 0.90 0.28 110 3.51 9.7 240 4 3 1.3 11.0 *Prior to the development of the future 4th Filing, Phase 2, undevelope * Storage Capacity determined using conditions will exist over a portion of Basin 34, and runoff will UDHYDRO POND, see output, pg flow to temp. swale #34. ** TC for subbasin 4-1 is 12.4 minute *** Tc for subbasin 6-1 is 15.8 minut En W v m y 0 Z n a M m D STc�rli!DCaCG.,.," 100 yriv� A /1n ICA .. DATA STORM DRAINAGE SYSTEM PRELIMINARY 0©Al0©©0101>000®0�®010000®© r•�� �3�C10�'�s��:6i7�m��l�F�C!��� .� IIIIINIIIIII i �i Ld►J i .. C)li no mF90 • Sri . G�E?�,'CdJ;E�i���������� / ► 11�1,!� � A 1' • 1•��111�/IrJ:SiirilL/��_.1wlJ- � ____� �. ,c. Figure 5-1 Tc=ZS.3+ 36Y VYY Fo^^ 11.3 6ye)C4t = ;w TYPICAL FORM FOR STORM DRAINAGE SYSTEM PRELIMINARY DESIGN DATA — (From: Wright -McLaughlin Engineers, 1969) DESIGN OF INLETS AND SWALES 14 1 UNLINED CHANNEL DESIGN CRITERIA 1 REFERENCE: 1 THE CITY OF FORT COLLINS "STORM DRAINAGE DESIGN CRITERIA AND CONSTRUCTION STANDARDS", MAY, 1984. 1 SECTION 7.2, UNLINED CHANNELS 1) MAXIMUM SIDE SLOPES = 4:1 1 2) MAXIMUM DEPTH OF FLOW IN CHANNEL = 4.0' 3) SUBCPITICAL FLOW ONLY 4) MINIMUM FREEBOARD = ADDITIONAL CAPACITY 1 FOP, 1 /3 OF THE DESIGN FLOW. 5) CHANNEL VELOCITY < 7.5 fps DUPING 1 THE 100—YR STORM. 6) CHANNEL VELOCITY > 2.0 fps DURING 1 THE 2—YP. STORM. 7) MANNINGS " n" = 0.0.35 (See Table 2-4) 1 8) MINIMUM SLOPE OF CHANNEL = 2.0% (FOR SLOPES LESS THAN 2.07. A 1 A SUBDRAIN SHALL BE PROVIDED) 9) MINIMUM RADIUS = 1 00' OR TWICE - THE TOPWIDTH OF THE DESIGN FLOW. LJ 1 11 1 1 I 151 ' Triangular Channel Analysis & Design Open Channel - Uniform flow 1 Worksheet Name: STONE RIDGE PUD ' Comment: SWALE #34, Q2=6.0 CFS Solve For Depth Given Input Data: Left Side Slope.. 4.00:1 (H:V) Right Side Slope. 4.00:1 (H:V) ' Manning's n...... 0.035 Channel Slope.... 0.0060 ft/ft Discharge........ 6.00 cfs Computed Results: Depth............ 0.89 ft Velocity......... 1.88 fps ' Flow Area.. 3.19 sf Flow Top Width... 7.14 ft Wetted Perimeter. 7.36 ft Critical Depth... 0.67 ft Critical Slope... 0.0267 ft/ft Froude Number.... FULL 11 I Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 1 I 1 1 [1 1 1 1 1 [I i 1 1 11 1 1 1 1 1 Triangular Channel Analysis & Design Open Channel - Uniform flow Worksheet Name: STONE RIDGE P.U.D.] Comment: Swale #34; Q100= 21.2 cfs Solve For Depth Given Input Data: Left Side Slope.. Right Side Slope. Manning's n...... Channel Slope.... Discharge........ Computed Results: Depth............ Velocity......... Flow Area........ Flow Top Width... Wetted Perimeter. Critical Depth... Critical Slope... Froude Number.... 4.00:1 (H:V) 4.00:1 (H:V) 0.035 0.0060 ft/ft 21.20 cfs 1.43 ft 2.58 fps 8.21 sf 11.46 ft 11.82 ft 1.12 ft 0.0226 ft/ft 0.54 (flow is Subcritical) Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 1 I 1 Triangular Channel Analysis & Design Open Channel - Uniform flow 1 Worksheet Name: STONE RIDGE PUD 1 Comment: SWALE #34, Q100 x 33% = 28.20 cfs Solve For Depth 1 Given Input Data: Left Side Slope.. 4.00:1 (H:V) Right Side Slope. 4.00:1 (H:V) Manning's n...... 0.035 ' Channel Slope.... 0.0060 ft/ft Discharge........ 28.20 cfs 1 Computed Results: Depth............ 1.59 ft Velocity......... Flow Area........ 2.77 fps 10.17 sf Flow Top Width... 12.76 ft Wetted Perimeter. 13.15 ft 1 Critical Depth... Critical Slope... 1.25 ft 0.0217 ft/ft Froude Number.... FULL 1 1 1 I I 1 1 1 Open Channel Flow Module, Version 3.42 (c) 1991 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 1 i /1/ 1 Swale Section F-F; Q100x1.333= 13.3 cfs Worksheet for Irregular Channel Project Description Project File c:\projects\sto\sto-ex33.fm2 Worksheet Existing Swale #33 ' Flow Element Irregular Channel Method Manning's Formula ' Solve For Water Elevation Input Data Channel Slope 0.006670 ft/ft '- Elevation range: 12.64 ft to 15.00 ft. ' Station (ft) Elevation (ft) Start Station End Station 0.00 15.00 0.00 35.30 4.00 14.00 8.00 13.00 ' 9.40 12.64 10.80 13.00 14.80 14.00 ' 19.60 15.00 35.30 15.00 Discharge 13.30 cfs Results F ' T H C ' C V 'S V F F ' 1 04/30/96 ' 07:45:58 AM Wtd. Mannings Coefficient Water Surface Elevation low Area Wetted Perimeter op Width eight ritical Depth ritcal Slope elocity elocity Head pecific Energy roude Number low is subcritical. 0.035 13.83 ft 5.56 ftz 9.72 ft 9.42 ft 1.19 ft 13.58 ft 0.024019 ft/ft 2.39 ft/s 0.09 ft 13.92 ft 0.55 Roughness 0.035 8/ FlowMaster v5.13 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Swale Section F-F; Q100x 1.333= 13.3 cfs Cross Section for Irregular Channel Project Description Project File c:\projects\sto\sto-ex33.fm2 Worksheet Existing Swale #33 Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Section Data Wtd. Mannings Coefficient 0.035 Channel Slope 0.006670 ft/ft Water Surface Elevation 13.83 ft ' Discharge 13.30 cfs I� 15. 14. r� C 0 14. d W 13. 13. 04/30/96 07:46:34 AM Station (ft) FlowMaster v5.13 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page I of 1 I I 1- Swale Section G-G; Q100x 1.333= 28.8 cfs Worksheet for Irregular Channel Project Description Project File c:\projects\sto\sto-ex33.fm2 Worksheet Existing Swale #35 Flow Element Irregular Channel Method Manning's Formula Solve For Water Elevation Input Data Channel Slope 0.010200 ft/ft Elevation range: 13.16 ft to 16.00 ft. Station (ft) Elevation (ft) Start Station ' 0.00 15.00 0.00 16.30 14.20 21.40 14.00 ' 33.70 13.16 39.90 14.00 43.90 15.00 48.40 16.00 Discharge 28.80 cfs IResults Wtd. Mannings Coefficient 0.035 Water Surface Elevation 14.16 ft Flow Area 11.03 ft, Wetted Perimeter 23.23 ft Top Width 23.13 ft L Height 1.00 ft Critical Depth 14.00 ft Critical Slope 0.023964 ft/ft Velocity 2.61 ft/s Velocity Head 0.11 ft Specific Energy 14.26 ft Froude Number 0.67 Flow is subcritical. I i I End Station 48.40 Roughness 0.035 20/ 04/30/96 FlowMaiter v5.13 04:54:40 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Swale Section G-G; Q100x 1.333= 28.8 cfs Cross Section for Irregular Channel Project Description Project File c:\projects\sto\sto-ex33.fm2 Worksheet Existing Swale #35 Flow Element Irregular Channel Method . Manning's Formula Solve For Water Elevation Section Data Wtd. Mannings Coefficient 0.035 Channel Slope 0.010200 ft/ft Water Surface Elevation 14.16 ft Discharge 28.80 cfs v c 0 W ' 04/30/96 04:54:47 PM 16.1 15A 15.( 14.! 14.( 13.P 13.0 0.0 z1/ ip n n� 0 C, 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 Station (ft) FlowMaster v5.13 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 No W.M m r s m m = m m M M. m m m s m m TABLE 2-4 MANNINGS ROUGHNESS COEFFICIENT, n ' Depth of Depth of Flow of Flow Greater 0.7— 1.5 feet Than 3.0 feet Bermuda Crass, Buffalo Cross. Kentuckv Blueaross a. Moveed to 2 inches _ ............._.._..._........ ....... 0.035 J............ 0.030 b. Length 4— 6 inches ................................................. 0.040 ..... 0.030 Good stand any grass Cl. Length of 12 inches ......... --- ...... -- ...................... 0,070 ...... --- ........ 0.035 b. Length of 24 inches ....... ......_.................. ..... .......... 0.100 .......... ...... 0.035 Fair stand any grass a. Length of 12 inches ............. ............ - ....... ,... ..._ ..... 0.060 .... ........... 0.035 b. Length of 24 inches .... ..........................................0.070 ..................... 0.035 F For stright channels without shrubbery or trees. REF: URBAN DRAINAGE AND FLOOD CONTROL DISTRICT J_\ACAD\DET\TABLES.DWG URBAN STORM DRAINAGE CRITERIA MANUAL, VOLUME 2 J NORTHERN ENGINEERING SERVICES TABLE 2-4 N SC>LE: N.n. 420 souTN NowES SUITE 202. Fr. COLLINS. cGLORADo 80521 s, „ F .,.Ew „ ,: ,, MANNINGS ROUGHNESS COEFFICIENTS, n �� r mmom $WON M AMI !• OEM STREET CAPACITY Z3/ I I I 11 I 11 I I I E TABLE 4-1 INITIAL STORM — STREET RUNOFF ENCROACHMENT Street ClasalMcatlan Maxhn Enoroaclnn LOCAL (Includes daces allevs No curb —overtopping. *Flow may spread to marginal access) crown of street. COLLECTOR No curb —overtopping. 'Flow spread rnust leave at least one lone width free of water. MAJOR ARTERIAL No curb —overtopping. *Flow spread must leave at least one—half of roadway width free of water in each direction. * where no curb overtopping exists, encroachment shall not extend over property lines. TABLE 4-2 MAJOR STORM - STREET RUNOFF ENCROACHMENT Street (7enelfloatlon ' Maxkn Encroachment LOCAL (Includes places, alleys Residential dwellings, public, marginal access. 8 collector) commercial and industrial buildings shall not be inundated at the round line unless buildings are flood—prooifed. The depth of water over the crown shall not exceed six (6) inches. MAJOR ARTERIAL Residential dwellings, public, commercial and industrial buildings shall not be inundated at the ground line unless buildings ore flood—Droofed. Depth of water at the street crown shall not exceed six (6) inches to allow operation of emergency vehicles. The depth of water over the hutter flowline shall not exceed 18 inches. In some cases. the 18 inch depth over the gutter flowline is more restrictive than the 6 inch depth over the street crown. For these conditions, the most restrivtive of the two criteria shall govern. O� W Uo cr >O s W 0 �z ZB Q o W . W M M M .W r W W M M " = Mao M r w" M m CITY OF FORT COLLINS GUTTER CAPACITY FOR DRIVE OVER CURB AND GUTTER Q= 0.56 z/n s ^ 0.5 y ^ 2.67 Project Description: STONE RIDGE P.U.D. FOURTH FILING, PHASE ❑ Project Number: 9613.00 File Number: STRCPPRW.WQ1 08-Mar-96 09:03 AM ATE DRIVE WEST' �C' �'"f t;; i T zJ4f> ) GN CRITERIA: 1) Initial Storm (2-Year) 2) No Curb Overtopping (0.39583'). Flow may spread to crown of street. 3) Street width from crown to flowline = 14'= Private Drive 4) n = 0.016 51 C"at r Width = 1 IT INPUT OUTPUT SLOPE %n Flow Spread from Flowline (ft) = 15.229 W = From Cl- of street to lip of gutter (fl) 12.8333 - Dc = depth of water over the crown (ft) = 0.025 A = 1 / street cross slope 50 2.00 Dw = depth at back of walk (ft) = -0.125 z2 = 1 / gutter cross slope 10.1818 9.82 Q1 4.583 z3 = 1 / back of curb slope 3.5789 27.94 Q2 2.429 z4 = 1 / gutter cross slope 10.1818 9.82 Q3 0.831 z5 = 1 / back of curb cross slope 3.5789 27.94 Q4 (-) 0.975 z6 = 1 / sidewalk cross slope 30 3.33 Q5 (-) 0.000 z7 = I / R.O.W. cross slope 50 2.00 Q6 0.000 s = longitudinal street slope (ft/ft) 0.006 0.60 Q7 ERR y = depth at the flowline of gutter (ft) 0.395833 Q TOTAL (cfs) 6. 2-YR T I IEORETICAL CAPACITY F = REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPACIT 0.8 (See Figure 4-2) ACTUAL ALLOWABLE GUTTER CAPACITY 6.87 0.8 QTOTAL (cfs) 49 2-YR ALLOWABLE CAPACITY northern engineering services, inc. CITY OF FORT COLLINS GUTTER CAPACITY FOR DRIVE OVER CURB AND GI -TITER Q=0.56z/ns^0.5y^2.67 Project Description: Stone Ridge P.U.D., Fourth Filing, Phase II Project Number: 9613.00 File Number: 100YRPR W. W Q 1 08-Mar-% 08:57 AM For 1/2 of the Street PRIVATE DRIVE WEST �cSit J i 34<a DESIGN CRITERIA: 1) Major Storm (100-Year) 2) Depth of Water Over the Crown Shall Not Exceed 0.5' (y= 0.8712'). 3) Street width from crown to flowline = 14'= Private Drive 4) n = 0.016 5) Gutter Width = 1.167' OUTPUT SLOPE % Flow Spread from Howline (ft) = 13.997 W = From CL of street to lip of gutter (ft) 12.8333 De = depth of water over the crown (fl) = 0.500 zl = I / street cross slope 50 2.00 Dw = depth at back of walk (II) = 0.350 z2 = 1 / gutter cross slope 10.1818 9.82 Ql (fixed) 7.409 z3 = 1 / back of curb slope 3.5789 27.94 Q2 (fixed) 3.298 A = 1 / gutter cross slope 10.1818 9.82 Q3 (fixed) 1.159 z5 = 11 back of curb cross slope 3.5789 27.94 (-) Q4 (fixed) 1.509 z6 = 1 / sidewalk cross slope 30 3.33 (-) Q5 (fixed) 0.004 z7 = 1 / R.O.W. cross slope 50 2.00 Q6 (fixed) 0.036 s = longitudinal street slope (ft/ft) 0.006 0.60 Q7 3.767 y = depth at the Bowline of gutter (ft) 0.8712 Q8 24.774 Q TOTAL (cfs) .93 100-YR THEORETICAL CAPACITY F = REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPACIT 0.8 (See Figure 4-2) ACTUAL ALLOWABLE GUTTER CAPACITY 38.93 ' 0.8 QTOTAL(cfs) 31.14 100-YR ALLOWABLE CAPACITY northern engineering services, inc. r am ■■r W r Ma M M r W r M M r was a m CITY OF FORT COLLINS GUTTER CAPACITY FOR DRIVE OVER CURB AND GUTTER Q = 0.56z/n s-0.5 y-2.67 Project Description: STONE RIDGE P.U.D. FOURTH FILING, PHASE II Project Number: 9613.00 File Number: STRCPPRV.WQI 08-Mar-96 08:31 AM PRIVATE DRIVE EAST DESIGN CRITERIA: 1) Initial Storm (2-Year) 2) No Curb Overtopping (0.39583'). Flow may spread to crown of street. 3) Street width from crown to flowline = 14'= Private Drive 4) n = 0.016 51 Gutter Width = 1.17' INPUT OUTPUT SLOPE % now Spread from Flowline (ft) = 15.229 W = From CL of street to lip of gutter (ft) 12.8333 Dc = depth of water over the crown (ft) = 0.025 A = 1 / street cross slope 50 2.00 Dw = depth at back of walk (ft) = -0.125 z2 = 1 / gutter cross slope 10.1818 9.82 QI 3.742 z3 = 1 / back of curb slope 3.5789 27.94 Q2 1.983 z4 = 1 / gutter cross slope 10.1818 9.82 Q3 0.679 z5 = 1 / back of curb cross slope 3.5789 27.94 Q4 (-) 0.796 z6 = 1 / sidewalk cross slope 30 3.33 Q5 (-) 0.000 z7 = 1 / R.O.W. cross slope 50 2.00 Q6 0.000 s = longitudinal street slope (ft/ft) 0.004 0.40 Q7 ERR y = depth at the flowline of gutter (ft) 0.395833 Q TOTAL (cls) 61 2-YR THEORETICAL CAPACITY F = REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPACIT 0.5 (See Figure 4-2) ACTUAL ALLOWABLE GUTTER CAPACITY 5.61 ' 0.5 O A (c s) 2.80 2-YR ALLOWABLE CAPACITY northern engineering services, inc. M Ism Ism M M M = M� M M M r w r 'm m CITY OF FORT COLLINS GUTTER CAPACITY FOR DRIVE OVER CURB AND GUTTER Q=0.56z/ns^0.5y^2.67 aject Description: Stone Ridge P.U.D., Fourth Filing, Phase 11 Dject Number: %13.00 e Number: I00YRPRV.WQI 08-Mar-96 08:47 AM r 1/2 of the Street :IVATE DRIVE EAST Q�s tti' .1 r�� ' '7— ='4=3 --SIGN CRITERIA: 1) Major Storm (100-Year) 2) Depth of Water Over the Crown Shall Not Exceed 0.5' (y= 0.8712'). 3) Street width from crown to flowline = 14'= Private Drive 4) n = 0.016 5) Gutter Width = 1.167' INPUT OUTPUT SLOPE % Flow Spread from Ilowline (fl) = 13.997 W = From CL of street to lip of gutter (ft) 12.8333 Dc = depth of water over the crown (ft) = 0.500 zl = 1 / street cross slope 50 2.00 Dw = depth at back of walk (ft) = 0.350 z2 = 1 / gutter cross slope 10.1818 9.82 Ql (fixed) 6.049 z3 = 1 / back of curb slope 3.5789 27.94 Q2 (fixed) 2.693 A = 1 / gutter cross slope 10.1818 9.82 Q3 (fixed) 0.947 z5 = 1 / back of curb cross slope 3.5789 27.94 (-) Q4 (fixed) 1.232 z6 = 1 / sidewalk cross slope 30 3.33 (-) Q5 (fixed) 0.004 z7 = 1 / R.O.W. cross slope 50 2.00 Q6 (fixed) 0.029 s = longitudinal street slope (fl/ft) 0.004 0.40 Q7 3.076 y = depth at the flowline of gutter (f1) 0.8712 Q8 20.228 Q TOTAL (c s) 31.79 100-YR TI IE'ORETICAL CAPACITY F = REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPACIT 0.5 (See Figure 4-2) ACTUAL ALLOWABLE GUTTER CAPACITY 31.79 ' 0.5 Q TOTAL (c s) 15.89 100-YR ALLOWABLE CAPACITY northern engineering services, inc. 1 1 1 1 1 I i 1 1 1 1 1 1 1 1 1 1 SLOPE OF GUTTER (7.) REDUCTION FACTOR. F 0.60 0.80 0.55 0.725 0.50 O.F:i 0.45 0.575 - 0.40- 0.50 1.0 .911111111111011 U6 cc o .6 c.� a Z .5 c.� M G W Cr .4 .3 .2 .1 .0 6 6 10 12 .0 2 4 14 V4111-0 SLOPE OF GUTTER (%) Figure 4-2 REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPA;,ITY Apply reduction factor for applicable slope to the theoretical cutter capacity to obtain allowable gutter capacity. 0 REFERENCE: Q U.S. DEPARTMENT OF COMMERCE i BUREAU OF PUBUC ROADS. 1965. �1 I��11�■11 II�R p 1�1111�� �11 1�11 ��1111 z 8/ t 0< LLQ QU <UUj WLLj W ��a ¢0 J Q 0'i �z Lu Lu 0 N ZN W Z" T_ 0 O0 Z0 e r w.m man r= ■r m m m m m m m m s m m RIPRAP CALCULATIONS I I r I 1 11 I 11 I Riprap Erosion Protection Calculations Reference: Urban Storm Drainage Criteria Manual, Volume 2, Urban Drainage and Flood Control District, March, 1969. From Section 5.6 Erosion Protection at Conduit Outlets, for Froude numbers up to 2.5. Location #1: At proposed curb cut, upstream end of Swale #34. Design Parameters: 100-yr Froude Number, 100-yr Design Discharge, Diameter of Circular Conduit, Width of Rectangular Conduit, Height of Rectangular Conduit, Tailwater Depth, F = 0.54 Q (cfs)= 21.2 cfs at Design Point 34. D (ft) = N.A. W (ft) = 12.0 H (ft) = 1.43 (Assumed) Y, (ft) = 1.43 (See pg.16, Appendix) Required Rock Size: Select required rock size from Figure 5-7 for circular conduits and from Figure 5-8 for rectangular conduits. Figure 5-7 is valid for O/D2.5 of 6.0 or less, Figure 5-8 is valid for Q/WH' S of 8.0 or less. Q/WH1-5 = 21.2/12(1.43)' 5 = 1.03 < 8.0, OK. Q/WH0-5 = 21.2/12(1.43)05 = 1.48 Y�H = 1.43/1.43 = 1.0 From Figure 5-8, Use Type L riprap for a distance of 3H downstream. 3H = 3(1.43)= 5.29 ft, Use a distance of 8 ft. G `-� i � J U N J O Zs O � U W O t 8V ZO < W U � S - W W , 60 40M O 3 0 pro O .2 .4 .6 .8 W Yt/H Use Ha instead of H whenever culvert has supercritical flow in the barrel. **Use Type L for a distance of 3H downstream. FIGURE 5-8. RIPRAP EROSION PROTECTION AT RECTANGULAR CONDUIT OUTLET. FIGURE5-8 IS VALID FOR 0/ WH1 5 OF 8.0 OR LESS. o w 0= DESIGN DISCHARGE IN CFS m W AND H= WIDTH AND HEIGHT OF RECTAPJGULAR CONDUIT IN FEET 9g� Y. = TAILWATER D�FTH i r m m m i = m = i = m m I= Erosion Control Calculations RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: Stone Ridge P.U.D. Fourth Filing, Phase II STANDARD FORM A COMPLETED BY: Mary B. Wohnrade DATE: April 30, 1996 Developed Erodibility Asb Lsb Ssb Lb Sb PS(Table 8-A) Sub -Basin Zone (ac) (ft) (%) 00 (%) (%) 34A Moderate 2.180 486 1.13 34B Moderate 1.920 3'6 0.77 Total = 4.100 435 0.96 77.5 Lb = sum (Lsb x Asb) / sum Asb Sb = sum (Ssb x Asb) / sum Asb Performance Standard (PS) = See Table 8-A CAWP5\DRA1NAGE\STNDFRMB.ERS EFFECTIVENESS CALCULATIONS PROJECT: Stone Ridge P.U.D. Fourth Filing, Phase II STANDARD FORM B COMPLETED BY: Mary B. Wohnrade DATE: April 30, 1996 Erosion Control Method C-Factor P-Factor Comment Hay Mulch 0.06 1.00 Basins' 34A and 34B Roads/Walks 0.01 1.00 Basins' 34A and 34B Gravel Inlet Filter 1.00 0.80 Basins' 34A and 34B Silt Fence Barrier 1.00 0.50 Basins' 32,33,35,36,37 Straw Bale Barrier 1.00 0.80 Basin 35 Bare Soil 1.00 1.00 n/a Major Performance Sub -Basin Area Calculations Basin Standard (%) (Ac) 34 77.5 34A 2.180 Roads/Walks = 0.59 acres Hay Mulch = 1.59 acres Gravel Inlet Filter Net C Factor = 0.59(0.01)+0.06(1.59)/2.180 = 0.05 Net P Factor = 0.80 EFF = (1-(0.05 x 0.80))x100= 96.0% 34B 1.920 Roads/Walks = 0.550 acres Hay Mulch = 1.370 acres Gravel Inlet Filter Net C Factor = 0.550(0.01)+1.370(0.06)/1.920 = 0.05 Net P Factor = 0.80 EFF = (1-(0.05 x 0.80))x100= 96.0% C:\WP5\DRA1NAGE\STNDFRMB.ERS Total= 4.10 (96.0%(2.180)+96.0(1.920)/ 4.10 = 96.0% 96.0% > 77.5% :. OK 3Z/ Li m m.M m m m m= m = = r==== m m m 3 co A D RAINFALL PERFORMANCE STANDARDS TABLE 8-A FOR FORT COLLINS, COLORADO FLOW LENGTH SLOPE ($) (FT) 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 6.0 7.0 8.0 9.0 10.0 20.0 30.0 40.0 50.0 100 200 70.9 72.0 74.6 76.3 76.8 78.4 79.5 80.3 81.1 81.6 82.1 82.5 83.0 83.4 83.6 83.8 84.0 84.7 84.8 84.9 84.9 300 72.4 77.0 78.2 78.8 79.5 80.0 80.5 81.2 82.1 82.5 82.8 83.2 83.6 83.9 84.0 84.2 84.3 84.8 84.9 84.9 84.9 400 72.6 77.4 79.1 80.3 80.9 81.2 81.6 81.8 82.5 82.8 83.1 83.5 83.8 84.1 84.2 84.3 84.4 84.8 84.9 84.9 85.0 500 72.7 77.7 79.4 80.5 81.3 81.9 82.7 82.8 83.0 83.1 83.3 83.4 83.7 84.0 84.2 84.3 84.4 84.5 84.8 84.9 84.9 85.0 600 72.8 77.9 79.5 80.6 81.4 82.0 83.0 83.2 83.5 83.8 83.9 84.1 84.1 84.3 84.3 84.4 84.5 84.6 84.9 84.9 85.0 85.0 700 72.8 78.0 79.7 80.8 81.5 82.1 83.0 83.3 83.5 84.0 84.2 84.4 84.4 84.5 84.5- 84.5 84.6 84.6 84.9 84.9 85.0 800 72.7 78.1 79.7 80.8 81.6 82.2 83.1 83.4 83.6 84.0 84.2 84.4 84.5 84.6 84.6 84.9 84.9 84.9 85.0 84.9 85.0 900 72.7 78.2 79.8 80.9 81.7 82.2 83.2 83.4 83.6 84.1 84.3 84.4 84.5 84.6 84.7 84.9 84.9 85.0 1000 1100 72.7 78.3 79.9 81.0 81.7 82.3 83.2 83.5 83.7 84.1 84.3 84.4 84.5 84.6 84.7 84.9 84.9 85.0 72.6 78.3 79.9 81.0 81.7 82.3 83.3 83.5 83.7 84.1 84.3 84.5 84.6 84.6 84.7 84.9 84.9 1200 72.6 78.4 80.0 81.0 81.8 82.3 83.3 83.5 83.7 84.2 84.3 84.5 84.6 84.6 84.7 84.9 84.9 1300 72.6 78.4 80.0 81.1 81.8 82.4 83.3 83.6 83.8 84.2 84.4 84.5 84.6 84.6 84.7 84.9 85.0 1400 72.5 78.5 80.1 81.1 81.8 82.4 83.4 83.6 83.8 84.2 84.4 84.5 84.6 84.7 84.7 84.9 85.0 1500 72.4 78.5 80.1 81.1 81.9 82.4 83.4 83.6 83.8 84.2 84.4 84.5 84.6 84.7 84.7 84.9 85.0 1600 72.4 78.5 80.1 81.1 81.9 82.4 83.4 83.6 83.8 84.2 84.4 84.5 84.6 84.7 84.7 84.9 1700 72.3 78.5 80.1 81.2 81.9 82.4 83.4 83.6 83.8 84.3 84.4 84.5 84.6 84.7 84.7 84.9 1800 72.3 78.6 80.1 81.2 81.9 82.4 83.4 83.7 83.8 84.3 84.4 84.5 84.6 84.7 84.7 84.9 1900 72.2 78.6 80.2 81.2 81.9 82.5 83.5 83.7 83.9 84.3 84.4 84.5 84.6 84.7 84.7 84.9 2000 72.2 78.6 80.2 81.2 81.9 82.5 83.5 83.7 83.9 84.3 84.4 84.6 84.6 84.7 84.7 84.9 2500 71.9 78.6 80.2 81.3 82.0 82.5 83.5 83.7 83.9 84.3 84.5 84.6 84.7 84.7 84.8 3000 71.6 78.7 80.3 81.3 82.0 82.5 83.6 83.8 84.0 84.4 84.5 84.6 84.7 84.7 84.8 3500 71.4 78.7 80.3 81.3 82.0 82.6 83.6 83.8 84.0 84.4 84.5 84.6 84.7 84.7 84.8 4000 71.1 78.6 80.3 81.3 82.0 82.6 83.6 83.8 84.0 84.4 84.5 84.6 84.7 84.8 84.8 4500 70.9 78.6 80.3 81.3 82.0 82.6 83.7 83.9 84.0 84.4 84.6 84.6 84.7-84.8 84.8 5000 70.6 78:6 80.3 81.3 82.0 82.6 83.7 83.9 84.0 84.4 84.6 84.7 84.7 84.8 84.8 W v STONE RIDGE P.U.D., FOURTH FILING, PHASE II EROSION CONTROL COST ESTIMATE Project Number: 9613.00 File Number: STOCSEST.WQ1 29-Apr-96 03:26 PM Units Estimated Unit Total EROSION CONTROL Quantity Price Price SILT FENCE L.F. 1873 3.00 5619.00 RIPRAP OUTLET PROTECTION CY 6 30.00 180.00 HAY MULCH AC. 0.062 3650.00 226.30 GRAVEL FILTER EA. 1 125.00 125.00 STRAW BALE BARRIER EA. 1 125.00 125.00 COST TO INSTALL EROSION CONTROL ....................... TOTAL = $6,275.30 AMOUNT OF SECURITY = 1.5 x $6,275.30 TOTAL = $9,412.95 OR TOTAL ACRES($650/ACRE)1.5 TOTAL ACRES = 8.322 COST TO VEGETATE _ $8,113.95 WHICHEVER IS GREATER. AMOUNT OF SECURITY =) 25 northern enaineerina services. inc. PROPoEEE A „w HLIxM P.HL ` WATERSTONE COURT ■ ■ ■ ■ BCFEDLA_E STORM "c. i, ■ ■ E. �`` ■ PROP08ED BWAL.E■ 37 ■ If •••• ♦♦♦ - \ ` l ■Lot 35 AS DRATE"I ♦ ♦♦ ACCESS G NUTY 4YMENT �L01 N CURB NLET do5 TYPE 4• ♦♦♦ •� ■ tiers ••..•��•♦•••■ 1'Icups ///••�•••• � �/ ♦♦♦ \ � �♦ E e 11 0035 EN ` ♦ /-' • �...- ■ : I o SECTION A. • /-- • / .� •' ■ �ESiGNA N ♦♦ \ ■ ..._....�.... "�SWALE NS SrervE Pb,o A �� ■ • �• '.. ) BECIION C-C i �� ` now; to o.ERNu vTF / ' - +/ ____ - ■ \ • PJxD -� ■ et'F r�. •'� '�. , oxISiING SWALE /36 ♦ "' ` � ■ pT9x •' 36 • T \1 37 (0 • ! qe •. , UNOFF TABLE AL /_/ psx �° -_'•• / _ ■ i' `: • ••• / /f • EXISTING Sw E d44 ■ ' �`'{ V 9t - " / ./• i ; = x., I �f i f' f a3 f ti IS,e r \.•• ExrsnNG SwALE 35■"i/ ♦�♦♦ •♦♦\ ,,', aB 47 `x - $■� ■■ ■■■ i i 42 00 `./ .•• Wf UNDERDRAIN d f' / �•♦ ♦♦♦ ■ a r, • /00 IF ♦ ■ Rarr ■A■•■ TER■A GO m ew• ogR.M. ON) MI lap 32 RBD JJ REND 34 3" 340 32 JJ JMNB W 34B 12! 256 4.10 2,19 1.92 44 w4 0.]] OBO OA 0.55 0.55 096 1.00 0.96 1.81 1J8 fi0 S3 3.2 NA NA. NA. NA _WA_ 683 643 21.2 11.8 11J OVERALL PONp OVERALL POND OVERALL PONp O'MERALL GONp OVEMLl POrvD 35 M RBD ]4,J5 36 605 1.34 O6J O.JS 0.]9 OA4 fi0 0.91 NA. NA. 21.6 J.Q OVERALL POND OrERµ1 POND •) `T.24 49 / s -`°_ \ ♦ ! 'b 1 39 \ �% tram■■• ♦♦ ,♦1H �`_ PR 1 VATE \`• f' N► �\ ! 'D'OTW.4FD 3 Ltf6 ♦♦♦ • LEGEND. NO 2 5 "WE PIPE •& ASIDE' —PORTLA i % `, ♦♦ / �` E5F�@mM&�prvs0 rO : • ■ - ENmxc STORM SEVEN f e IIH .e 51 ♦♦�'-- _ `1 O ® , f - `••` _ a ,- ----- EN STING STORM SEVEN INLET ` i. , L ' iA / ♦ x `'a- •, 37 35� �.. _ r.\'•MR'• ♦ ■ i- PROPOSED STORM sf R 3♦ BWALE• - ♦ ■ ��» PROPOSES STORM SERIES INLET f • x - ♦�' f id34. ♦ W ♦ _ ♦J.. r. ♦ ■ — zO— Ex PROPOSED OcacnwOTOONUN♦ , iPROx DRAINAGE eourvONrS •.......• Se 5�n` A ' , '� ♦S �C • • � 01 � Ru;w rcvOwrw j\ / ! ♦ .M ♦ �� ■ � I xqf � AREA IN ACRES • \ IT , _i ♦♦♦ / /(' C\ 59 601f f a, '�♦♦�• .•2� ♦ ♦' AOEZBx vOixr T , f_ v.� / bN A • ■■�� 8� �.. �..� PROPERTY BpMNBRT - ___ '`\ 62 - � ■ •� ......... GTv sTE IwuwcE epuxom ■ z ] - ' — PRIOR zNI ARNIA / EXISTING s PRIVATE &..• 64 az ♦] ■ ALE FEAR ARROVE mii 31 _ A q� • A•. \ r6�_ ■ ' a ♦ • 1.923 W F t F SECTION 1 \ (SEE ESNWGE REPORT FOR �x, r F .wO c cl ■ ♦♦ ♦� 1 ••■h •i E . �I ♦� • M �, �--� •■ �- n ■ % 19 ,��'v ♦ 26 j'. a NORTH •• � i •y ••�`'• ♦��.. •ft.. �, M 20 !' M zs GRAPHIC SCALE v A ♦ •♦♦ ♦ / j x 5 16 ♦ ♦ .Lf :/ �• �•� zA� 22 v `- 24 Rv _ } ... jW i • ♦ — \'' �♦ 1 t• I ♦ / iZ I r Nr •��• ♦•� ♦4♦• �♦ 23 ■ u •♦•» ♦ ♦ . - _ F' c I■ • d AREA OF SITE- 6.322 ACRES EX TIN 0 THE FILING -V ■ 111 �� .TOPZ ' ISTRIG .oTAv r•w .n:N <. x __. 33 - - ALE d33 ■ DETENTION POND \ ■ aR A - 256 'I/ _ ■ �- """ ---- - - �� .--le ■ CITY T FORT LANAPCOLLINS, COLORADO YYY v _ Y _ ______ __ - ■ UTILITY PLAN APPROVAL OE \■■•■■•••■•■•u•■■•■••■•••■u ■•■•■■u■■u■■u•■■■■■■■■■■■■■•■■■■u■u■■ .. _.. i. y.._.._ —-------- ----- -- ---- - - - -- — -- — --- -- — - ---- -- ---- RfCNm THE "TA .wo fM, anon w ■RATIO' AT A7LNIEEING ww • B FIOItBETOOTH _ _ _ _ ROAD .._.-- -- — -' — MS P STON[ATl - CHECKED Bn. ~ ■N ••M ■ - FOURTH TALP WISE P_ — __ — - _ - THE srap �Mv vrun n r _ - - RE WAW NOT FOR CONSTRUCTION No. ReNsions B Dole Sheet Pr EDT Print Date: STONE RIDGE P.U.D. FOURTH FILING, PHASE 2 NORTHERN ENGINEERING SERVICES 9613.00 - 420 SOUTH HOSES SUITE 202. Fr.. COLLINS. COLORADO 80521 SCALE: 1'= 40SCALEo 40' SAY-BT�6� FINAL (970) 221-4156 DESIGNER :MEW CHECKED BY: RAC DRAINAGE PLAN % DRAFTSMAN.ACAD PREPARED:OS 01 96 Sheet•