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HomeMy WebLinkAboutCT 02-14-06; BRESSI RANCH PA 12 UNIT 6; PRELIMINARY DRAINAGE REPORT; 2004-04-01PRELIMINARY DRAINAGE REPORT FOR BRESSI RANCH RECREATION CENTER OPEN SPACE 2 CARLSBAD, CALIFORNIA APRIL 2004 Prepared For: LENNAR PARTNERS 18401 Von Karman Avenue, Suite 540 Irvine, CA 92612 Prepared By: PROJECTDESIGN CONSULTANTS 701 B Street, Suite 800 San Diego, CA 92101 Project No. 2407.00 Gregorys. Shields, PE Registration Expires RCE 42951 03/31/06 42951 Ex''. 03-31-05 Jl^'h Prepared By: RI Checked By: MW TABLE OF CONTENTS Section Page 1.0 INTRODUCTION 1 2.0 PROJECT DRAINAGE BACKGROUND: MASS GRADING AND ULTIMATE CONDITION HYDROLOGY 3 2.1 Mass Grading Hydrology 4 2.2 Ultimate Condition Hydrology 4 3.0 HYDROLOGY CRITERIA AND METHODOLOGY 4 3.1 Hydrology Criteria 4 3.2 Hydrology Methodology 5 3.3 Explanation of AES Rational Method Software 6 4.0 HYDROLOGY ANALYSIS RESULTS 7 5.0 CONCLUSION 9 FIGURES 1.0 Vicinity Map 2 TABLES 1.0 Hydrology Criteria 5 2.0 Pipe Capacities 8 APPENDICES 1.0 2, 10, lOO-year: 6-, 24-hr. Isopluvials Maps 2.0 Poroposed Conditions Rational Method Computer Output 3.0 Flowmaster Normal Depth Calculations EXHIBITS A Proposed Conditions Hydrology Map 1.0 INTRODUCTION This drainage report supports the preliminary design of the proposed storm drain improvements associated with Bressi Ranch Recreation Center OS-2 (Project). The overall Bressi Ranch development is located in the City of Carlsbad (City) and is bounded by: 1) Palomar Airport Road to the north, 2) Melrose Drive to the east, 3) El Camino Real to the west, and 4) Poinsettia Drive to the south. Within the Bressi Ranch development, the Project is bounded by: 1) Planning Area 10 (PA) to the west. Planning Area 7 to the northeast. Planning Area 9 to the east, and Planning Area 8 to the south. See Figure 1: Vicinity Map, for the project location. In general, the Project is part of the Bressi Ranch master planned development consisting of 15 mixed-use PAs. The existing and proposed Project drainage pattems generally traverse the site southwesterly toward the intersection of Gateway Road and Alicante Road and the intersection of EI Camino Real and Town Garden Road. From a construction standpoint, the recreation center site will have been mass graded in preparation for the Project precise grading and construction of the storm drain improvements. The drainage analyses presented herein reflect a Tentative Map level-of-effort, which include: 1) 100-year storm event hydrologic analyses using relative pad and street grades, 2) normal depth hydraulic calculations to determine onsite storm drain sizes. Detailed hydraulic storm drain analysis to finalize storm drain sizes and to determine the hydraulic grade lines (HGL) will be provided during final engineering. Additionally, hydraulic analyses for inlets, ditches, and erosion protection measures etc. will also be provided during final engineering. Therefore, the purpose of this report submittal is to acquire from the City: 1) concept approval of the proposed storm drain layout, 2) approval of the Methodology used in the evaluation ofthe Project storm drain system hydrology, and 3) identification of critical path drainage issues that need to be addressed during final engineering. T:\Water Resources\2407.3-Bressi Residential\Open Space 2\lst Subminal\Report\2407DR.DOC Lu O o o Co a. Figure 1: Vicinity Map 2 T:\Water Resources\2407.3-Bressi ResidentiaI\Open Space 2\lst SubmiUal\Report\2407DR.DOC The Project will meet State NPDES construction and municipal stormwater permit requirements. The construction phase BMPs associated with the Project will be addressed in the Grading and Erosion Control Plans and the SWPPP. The post-construction BMPs for the Project are currently being developed in conjunction with the overall Storm Water Management Plan (SWMP) for Bressi Ranch. The SWMP was provided as a part of the approved master Tentative Map submittal. The final post-construction BMP design will be provided during final engineering. 2.0 PROJECT DRAINAGE BACKGROUND: MASS GRADING AND TM ULTIMATE CONDITION HYDROLOGY From a regional drainage perspective, the Recreation Center OS-2 site storm drains convey Project storm runoff to Witley Way and thence to the backbone storm drain improvements within Alicante Road that will be constructed with the overall Bressi Ranch mass grading and backbone improvements, prior to the start of the Project construction. The project runoff is tributary to the detention basin located along Alicante Road. Since the project runoff is tributary to the backbone storm drain system and is tributary to a detention basin, the hydrology analysis in this report focuses on the Project impacts on the backbone storm drain system. As previously mentioned, the overall Bressi Ranch mass grading and backbone drainage improvements will be completed prior to the start of Project construction. Note that the mass grading hydrology accounted for the Project storm runolT in the design of the backbone drainage system. However, the Project hydrology in this report supersedes the hydrology used to design the backbone storm drain improvements. T:\Water Resources\2407.3-Bressi ResidentialVOpen Space 2\lst Submittal\Report\2407DR.DOC The following sections address the mass grading and ultimate condition hydrology. 2.1 Mass Grading Hydroiogy The Project will be mass graded as part of the overall Bressi Ranch project (City Project No. CT 00-06). The drainage for the mass graded condition is addressed in the approved PDC "Drainage Report for Bressi Ranch Mass Grading," dated January 2003. The Mass Grading report provides: 1) mass graded condition 1 OO-year storm flows, and 2) ultimate condition 1 OO-year storm flows within the Recreation Center OS-2 site. The mass graded condition, which is assumed to be the existing condition for this Project, consists of a mass graded pad tributary to a desilting basin located east of Alicante Road at the southwest comer of PA-10 and then to a detention basin west of Alicante Road. The following section provides a discussion of the ultimate condition hydrology. 2.2 Ultimate Conditions Hydrology The Project hydrology analysis, included herein, supersedes the ultimate condition hydrology calculations contained in the mass grading report, since the Project hydrology reflects the current site layout, and roadway and storm drain alignments. Specifically, the mass grading ultimate conditions hydrology was based on the October 2002 concept layout of the Project storm drain system. See Exhibit A for the Project hydrology map. 3.0 HYDROLOGY CRITERIA AND METHODOLOGY 3.1 Hydrology Criteria This section of the report summarizes the drainage criteria that were used in the hydrologic T:\Water Resources\2407.3-Bressi ResidentialXOpen Space 2\lst Submittal\Report\2407DR.DOC analysis and key elements of the methodology. Also included is a description of the computer model used in the computations. Table 1: Hydrology Criteria Design Storm: lOO-year, 6-hour storm. Land Use: Recreational, Parking, and roadway Runoff Coefficients: Based on criteria presented in the County of San Diego Hydrology Manual. C=0.45 for good grass cover, C=0.70 for 50% hardscape, C=0.85 for commercial, and C=0.95 for roadway. Hydrologic Soil Group: Soil Group 'D' per the County of San Diego Hydrology Manual. Intensity and Time of Concentration: Based on criteria presented in "Standards for Design and Construction of Public Works Improvements in the City of Carlsbad," Drainage - Design Criteria section, dated 4-20-93 and the County of San Diego Hydrology Manual. See Appendix 1 for the County Isopluvials. Minimum Tc = 6 min used per County of San Diego Hydrology Manual and AES Rational Method Program. 3.2 Hydrology Methodology The hydrology methodology for the Project is straightforward. The Modified Rational Method was used to determine the lOO-year storm flows for the design of the storm drain improvements. The goal of the Project hydrology analysis was to: • Determine more detailed design storm flows for the sizing of the intemal site storm drain system and storm drain laterals that connect to the backbone storm drain improvements. From an analytical perspective, the Project hydrology was prepared using street and pad grades and approximate invert elevation where available for the storm drain slopes and the actual storm drain system layout, in contrast to the mass grading report hydrology, which was determined using the October 2002 site storm drain system layout. 5 T:\Water Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\2407DR.DOC • Verify that the Project does not adversely impact the backbone storm drain improvements. A comparative analysis was performed between the backbone improvements design runoff and Project hydrology runoff at locations within the backbone storm drain system to determine Project impacts. • The Advanced Engineering Software (AES) Rational Method Program was used to perform the hydrologic calculations. The following section provides a brief explanation of the computational procedure used in the computer model. See Appendix 2 for Project hydrology Rational Method computer output and Exhibit A for the Project hydrology map. 3.3 Explanation of AES Rational Method Software The Advanced Engineering Software (AES) Rational Method Program was used to perform the hydrologic calculations. This section provides a brief explanation of the computational procedure used in the computer model. The AES Rational Method was used to determine the lOO-year storm flows for the Project. The AES Rational Method Hydrology Program is a computer-aided design program where the user develops a node link model of the watershed. The program has the capability of estimating conduit sizes to convey design storm flows, or the user may input specific conduit sizes and open channels. Soil types used in the model are based on hydrologic soil groups as outlined in the Conservation Service's Soil Survey for San Diego County. The rainfall intensity distribution and runoff coefficients utilized by the program can be user-specified to be based on either the County of San Diego or the City of San Diego Drainage Design Manuals. Developing independent node link models for each interior watershed and linking these sub- models together at confluence points creates the node link model. The program allows up to five streams to confluence at a node. Stream entries must be made sequentially until all are entered. The program allows consideration of only one confluence at a time. The program has the TAWater Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\2407DR.DOC capability of performing calculations for 17 hydrologic and hydraulic processes. These processes are assigned code numbers, which appear in the printed output. The code numbers and their meanings are as follows: CODE 0: ENTER Comment CODE 1: CONFLUENCE analysis at node CODE 2: INITIAL subarea analysis CODE 3: PIPE/BOX travel time (COMPUTER estimated pipe/box size) CODE 4: PIPE/BOX travel time (USER specified pipe/box size) CODE 5: OPEN CHANNEL travel time CODE 6: STREETFLOW analysis through subarea, includes subarea runoff CODE 7: USER-SPECIHED hydrology data at a node CODE 8: ADDITION of subarea runoflf to MAIN-Stream CODE 9: V-GUTTER flow through subarea CODE 10: COPY MAIN-stream data onto memory BANK CODE 11: CONFLUENCE a memory BANK with the Mainstream memory CODE 12: CLEAR a memory BANK CODE 13: CLEAR the MAIN-stream CODE 14: COPY a memory BANK onto the Main-stream memory CODE 15: HYDROLOGIC data BANK storage fiinctions CODE 16: USER-SPECIFIED Source Flow at a node 4.0 HYDROLOGY ANALYSIS RESULTS In general, the Project hydrology results presented herein were used to determine: 1) Project storm drainpipe sizes within the Recreation Center site, and 2) verify that the project does not T:\Water Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\2407DR.DOC adversely impact the backbone storm drain system. The proposed Project causes a slight localized increase in flow to the PA-10 storm drain system at the catch basin in PA-10. This catch basin is the connection point for the onsite storm drain system of the Project. The PA-10 runoff at this location is 7.05 cfs while the Project runoff is 8.15 cfs for an increase of 1.1 cfs (see table 2). This increase is due to the higher runoff coefficients used in the current hydrology calculations. However, as shown in table 2, the increase will have little effect on the backbone system since there is adequate capacity in the backbone system for the increase. See Appendix 3 for Flowmaster Normal Depth Calculations. Table 2: Pipe Capacities PA-10 PIPE CAPACITIES Pipe Pipe Mass Graded Proposed Pipe Location Dia. Slope Flow Flow Capacity (in) (ft/ft) (cfs) (cfs) (cfs) Wiley Way 3+00 18 0.018 7.05 8.15 14.09 Dunham Ave. 11+00 18 0.06 18.53 19.63 25.73 See Appendix 2 for the Project Rational Method output. Also, see Exhibit A for the ultimate conditions Project hydrology map. 6.0 CONCLUSION This drainage report supports a preliminary design of the proposed storm drain improvements associated with Bressi Ranch Recreational Center Site (Project). From a construction standpoint, the Project site will have been mass graded in preparation for the precise grading and construction 8 TAWater Resources\2407.3-Bressi ResidentiahOpen Space 2\lst Subniittal\Report\2407DR.DOC of the storm drain improvements. The drainage analyses presented herein reflect a Tentative Map level-of-effort, which includes: 1) 1 OO-year storm event hydrologic analyses using street grades and approximate invert elevations where available, for pipe flow routing, 2) normal depth hydraulic calculations to determine onsite drainpipe sizes. Detailed hydraulic storm drain analysis to finalize the storm drain sizes and to determine the hydraulic grade Unes (HGL) will be provided during final engineering. Additionally, hydraulic analyses for inlets, ditches, and erosion protection measures etc. will also be provided during final engineering. Therefore, the purpose of this report submittal is to acquire from the City: 1) concept approval of the proposed storm drain layout, 2) approval ofthe methodology used in the evaluation of the Project storm drain system hydrology, and 3) identification of critical path drainage issues that need to be addressed during final engineering. The project causes localized increases in the 1 OO-year storm flows within the PA-10 storm drain system. The localized increases in the storm runoff can be accommodated in the backbone storm drain system with no adverse impacts based on a comparison of the proposed Project runoff versus the backbone storm drain system capacity. The Project will meet State NPDES construction and municipal stormwater permit requirements. The construction phase BMPs associated with the Project will be addressed in the Grading and Erosion Control Plans and the SWPPP. The post-construction BMPs for the Project are currently being developed in conjunction with the overall Storm Water Management Plan (SWMP) for Bressi Ranch. The SWMP was provided as a part of the approved master Tentative Map submittaL Thefinal post-construction BMP design will be provided during final engineering. TAWater Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\2407DR.DOC APPENDIX 1 2,10, & lOO-YEAR 6- & 24-hr ISOPLUVIALS TAWater Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\Appendix.DOC 3 4 Hours Directions for Application: (1) From precipitation maps determine 6 hr and 24 lir amounts forthe selected frequency. These maps are included in the County Hydrology Manual (10,50, and 100 yr maps Included in the Design and Procedure Manual). (2) Adjust 6 hr precipitation (if necessary) so that it is within the range of 45% lo 65% of the 24 hr precipitation (not applicaple to Desert). (3) Plot 6 hr precipitation on the right side of the chart. (4) Draw a line through the point parallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Application Form: (a) Selected frequency A?J?. year 24' 2 ••Oin. 24 (b) PQ = 2A0in.,P24 = 5.10 ,-- = 56_%m (c) Adjusted Pg<2) (d) = min. (e) 1 = In./hr. Note: This chart replaces the Intensity-Duration-Frequency cun/es used since 1965. ........... "li" "is" "'3" 3'.S "4 -4.5" "5.S" ""e" buralldn 1 . . . ..... _ ....... ""1 i "i ..... v 5 ....„ 2.63 3.95 5.27 6.59 7.90 9.22 10.541 11.86 ...... 13.17 14.49 15.81 3.i"B 4.24 5.30 6.36 7.42 8.48 J Weo "ii'.ee 12772 10 1.S8 2.S3 3.37 4.21 5.05 5.90 6.74 "8.42 16".Ti ts 1.30 1.9S 2.59 3.24 3.69 4^54 "5.19 ""s;84 6^49 7.13 "7.78 JO T.OB' V.62 2:i"5 "iM "3.23 377 Tsi" 'Xes 5.39 5.93 6.46 ~Z5 1.40 1.87 2.33 2.80 3.27 3.73 4.26 4:67' 5.13" sieo "3d "oM 1.24 2.49 2'.90 3:32' "3:73 "4; 15 4,56 "iM' 40 0.69 1:63 TM 2.67 2;4i "2.76 3; 16 3;4S 3.79 4.13 • M 0.60 6.90 "i;i9 i.49 1>9 2:69' 2.69 2.9B 3.28 3.58 BO 0.53 0.80 iM "i.33 i"59 •i'.86 2.12 i'M "2.65' "2.'92 •3.18 90 6.41 0.61 0.62 "i.62 i.23 "1.43 iisj 1.84 2.04 2,25 2.45 120 "Kzi 6.i5i oM "6.85 1:62 i;i9 1.36' i.53 1.70 i.87' 2.64' "isd a44 6.S9 6.73 6.88 i.03 "1.18 1.32 1.47 1.62 i.76 180 0.26 0.39 6.52 aes' a78 aai i;64 i.is 1.31 i.44 1:57 •246' 0.^' ajo 6.43 6.64 6.65 6.76 6.87 oM i;68 1.19 i.36 300 0.19 0.28 0.38 0.47 056 656 "6.75 6:85 0.94 1.03 1.13 360 0.17 0.25 a33 6;42 6750 6.58 6.75 0.64 6792" FIGURE Intensity-Duration Design Chart - Template HazMal/County Hydrogeology Manual/lnl.Dur Design Chart.FH8 15 20 30 40 50 1 Minutes Duration 3 4 5 6 Hours Directions for Application: (1) From precipitation maps determine 6 hr and 24 hr amounts forthe selected frequency. These maps are included in the County Hydrology Manual (10,50, and 100 yr maps included in the Design and Procedure Manual). (2) Adjust 6 hr precipitation (if necessary) so that it is within the range of 45% to 65% of the 24 hr precipitation (not applicaple to Desert). (3) Plot 6 hr precipitation on the right side of the chart. (4) Draw a line through the point parallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Application Form: (a) Selected frequency 10 ._ year (b) PB = lJL5 in..P„, = 325 •p. — = 57 0/^(2) 24 in. (c) Adjusted Pg^^* = i.-_*J5 i (d) \^ = min. (e) I = in./hr. Note: This chart replaces the Inlenslty-Duration-Frequency curves used since 1965. i 1.3 -Jj— - - . 2.5 ""3" 3.5 4 "Ts" S , 5.5 ... .. ... . buiatlon ""T ......... ....... i ~ " 1" • r 1' i""' S , 5.5 ... .. ... . 1 5 2.63 3.95 5.27 6.59 7.90 9.22 10.54J 11.86 13.17'14.491 15.81 ""'7 •3.18 "4.24 •5.30 "6.'36 .„ 8.46 1 10.60 ...... 11.66 12.72 10 1.68 2.53 3.37 4.21 J 5.05 5.90 6.74 7.68 "§727" 16". 11 IS 1.30 1.95 2.59 3.24 'i.si T.i9 6^49 7:13' 7.78 Jjj, TM' iJai iiri's '2.69 •3:23 Sf? Tsi" "AJS 5.39 "siss" 6.46' -js oM 1.46 1.87 "£33 2780 3.27 3.73 4.20 6.13" '5766 "0.83 1.24 i.'66' 2.07 '2.49 2.90 3;3"2" '3:73 4.15 4.56 4.98 40 0.69 1.63 1.38 'i772" 2.67 2;4"i "2.76 sii 6 3.4s 3.79' 4.13 6W 6.90 1719 1.49 1:79 2.69' 2:39' "2.69 "2:98 3:28 3.58 60 0.53 6.80 i."68 i:33 i759 1.86 "•2.12' •2;39 "•2.65' '2,'92' "3.i"8 '90 6.61 1.62 i.23 "i.43" ilea "1.84' 2.04 2,25 2.45 120 0.34 6.51 6.iS8 0.65 1.02 1.19 1.36 "i.53 i:70 "i.87' '2:64' ""iso '659" 6.44 a59 6.73 6.88 j.M "1.18 i.32 i.47 1.62 i.'76 ........ 180 0.26 0.39 6.52 "6.65 6.78 6.91 1.04 I.ie 1.3i 'i.44 -240 •6.22' oM 6.43 "6.54 aes •6.76 6.87 "6.'98 i;08 i.i9 1.30 300 0.19 0.28 0.38 0.47 ........ 0.S6 oiee "6.75 0.65 6.94" •i7i"3 360 0.17 10.25 0.33 6750 6.68 "ae? 6.75 "6.84' 6792 i".'66" FIGURE Intensity-Duration Design Chart - Template HazMat/County Hydrogeology Manual/lnt.Dur Design Chart.FH8 20 30 Minutes 40 50 1 Duration Directions for Application: (1) From precipitation maps determine 6 hr and 24 hr amounts for the selected frequency. These maps are included in the County Hydrology Manual (10, SO, and 100 yr maps included in the Design and Procedure Manual). (2) Adjust 6 hr precipitation (if necessary) so that it is within the range of 45% to 65% of the 24 hr precipitation (not applicaple to Desert). (3) Plot 6 hr precipitation on the right side of the chart. (4) Draw a line through the point parallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Application Form: (a) Selected frequency . year (b) Pg = "LM in., P24 = 2 ._O^P.p- = «_7_ ./,(2) (c) Adjusted PQ^'^ = 1^3.0 in. (d) tjj = . min. (e) I = in./hr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965. "5.5" ......... 1.3 "2" 3 3.5 4 4.5 5 ' "5.5" "s" butatlon" ...... . fi"" ....... i• i i"'" ~'l 5 ..,.„. 2.63 ......... 3.95 5.27 6.59 7.90 9.22 10.54 11.88 13.17 14.49 15.81 's.'i'B 4.24 5.30 •"6.36 7T42 8"748" '9754" i6".66 "ii'."66 "12772 10 1.68 2.53 3.37 4.21 5.05 5.90 6.74 7.58 8.42 9.27 10.11 IS 1.30 1.95 2.59 3.24 '3789 "4754 "5719 "S.M 6:49' 7713' '7.78 20 Tibs" 1.62 "sM "3723 3.7f ........ ~A.e5 "5.39' "5:93 "6.46" 25 0793 i.'4'6 i.'8'7 Y.33 "2780 3773" "4.20 5.'i'3" "5760 30 0.83 i.2'4 i.66 '2767 2.49 2.90" '3:32" '373 4:15 4.'56 4.98 40 '6.69 i.63 i".38 2.07 2:41 "2.76 '3.ib 3:4s 3.79 4.13 56 6.60 6.90 "i7i9 i.49 l779 2769 2.~3g"' "2.69 "2:98 3:28 3.58 60 0.53 0.80 1.06 1.33 1.59 1.86 2.12 2M "2.65" "2.'g2 " " ' ""96 0.41" 6.61 6.Bi 1.62 "i.23 'i.4'3' i763 1.84 2.04 2,25 2.45 126 "6734" 6.51 6.68 "6.85 1762 i7i9 'i.36" 'i.53' i:76 'i.i37' "2:64' 150 "6.29" 6.44 d59 6.73" 6.88 1.03 "i.is l732 i.47 1.62" "i.'76 180 0.26 0.39 6.52 "6765 '6778 6.91 i764 i.ie 1.3i •l'.'4'4 ........ 240 0.22 a33 6.43 "6.54' aes 6.76 6.87 "6;9e 1:68 i.i9 1.30 300 0.19 0.28 0.38 0.47 0.56 oie "6.7S' 6:85 0.94 1.03 1.13 360 0.i"7"" 6.25 "6733 "6742" "aso "6767 0.75 "6784 6J92 "i.'oo" FIGURE Intensity-Duration Design Chart - Template HazMal/County Hydrogeology Manual/lnt.Dur Design Chart.FHS Orange Cout^ 4,.0. / / 7^ / / / (06115^'' A Riverside County / / ,- V^"^Lr?'\ ) / C\ \ 4.0—, 3.5., N-..^ \ \ \ A 2.5 -^y r K/i \ I ^43^^>^^S% » » /' ^ \ \ V « \ \ \ \ '•• / ^ ^ / vC ^ \ l^jty { ^ '» 50 \ >k. \ ' » * » ' / ^ I \ ^"3.5:^^ J1 ^^ -^^ \\ PaioiflaJ*)unlao 5 I \ \ \ \\ I I 2.75 \ N 375 \ N^' 3.0 » . ' ! ' > » \ \ Wfenjer .' \ • \ /X\ \ 4.5.-' V \ Sanla Cr«* » \ \ Ysabrf* >• ' Leucadia Endnitas Cardiff l)y the Sea Solana Beadi Del Mar —4.0 .A' ^.•Sjuliaft Hit 5.0 \ to V 5 ^7 \ firings » 2.5" -2.5—- 5.0 La Jolla Padfu: Beach Mission Beach Point Loma HOipflim\ Risflrioir \ ^•^3.5" Agua Cariente Springs 2.75 Besenxxr 3.0 -'^ Vpulzura 3.6 } • ^-^ ^Zo-y ( / ^—" . >"-"-/3.0-. Campo Tguaia EstadoslW**' County of San Diego Hydrology Manual Bainfall Isopluvials 100 Year Raiitfall Event - 6 Hours /V' Isopluvial (inch^) Map Notes State{^ Projection, Zones. NAD83 Cre^ Date: June 22.2001 NOTTO BE tJSED FOR DESIGN CALCULATIONS 7.5 MILES amecP / Orange Coijnty 10.0 7"n 12.0 Riverside County i—;—1 —s. l , San Di^p^o.|7.0;J4nl'y, \„ \ 10.0-, >_7.Q 8.0 ! . Paioms^Moui^!''"'' 10.0 X g-Q \ \ ' 8.0 • ' * « > » » . 1 > 5.0 few uW^^ "~ 'H'x 3 o o c 3 ^l/ailyJqrdra^)kibAisn]b/a]ly.aai] County of San Diego Hydrology Manual Rainfall Isopluvials 100 Year Rainfall Event - 24 Hours / V Isopluvial (inches) Map Notes Stateplane Projection. Zones. NM3B2 Creation Date: June 22.2001 NOTTO BE USED FOR DESIGN CM.CULATiONS MLES 7.5 amecP i Point Loma Iguana County of San Diego Hydrology Manual Rainfall Isopluvials 10 Year Rairfall Event - 6 Hoiffs /V' Isopluvial (inches) IVbp Notes Statepfae Pitjectioa Zones, NAD83 Creation Date: June 22,2001 NOTTO BE USED FOR DESIGN CALCULATIONS MLES 7.5 ametP County of San Diego Hydrology Manual _ \:x--4.b 1 \^^^., 3.'5 3.0 ,tofflfi-»{flls \ \ ^^^ 3i ) / •JN » \ « ' V 2.5 \ \ \ \ \ \ \ ^3->^• ' \^fil'55»Hxaw«sVV v/.^^^^ \ .t \ V"-- -' / • \ \ \\J \ Rainfall Isopluvials 10 Year Rainfall Event - 24 Hours /V' Isopluvial (inches) WteKfcanos/BajaCartfonw i o Map Notes Stateplane Prtjedioa Zones. NAD83 Creation Date: June 22,2001 NOTTO BE USED FOR DESIGN CALCULATIONS 7.5 MLES ame<P Coiinty of San Diego Hydrology Manual Rainfall Isopluvials 2 Year Rainfall Event - 6 Hours /V' Isopluvial (inches) Map Notes Stateplane Projedioa Zones. NAD83 Creation Date: Ine 22.2001 NOT TO BE USED FOR DESIGN CALCUUTIONS MLES 7.5 Orange Coui^ River si de County \ SAft'J3ieVc-G..ou"nt-.y \ PaiomarMoiBitalrr.. ATI®N •tf^' ttesfrmir 3\ 1.0.^ 1.2.. 'OeuHo Wells Leucada Endnftas Cardiff by the Sea Solana Beadi Del Mar .-'-35.. /4.o:yv LaJoHa Padfic Beach Mission Beach Ocean Beach y^/ ^^^^^^r^^f-r^^^y^/^ ^\ \ \ —--45-''' / 1 \ \V\\ / N ^ rXL^i^:OTj^r>^^^ -'->'' )> i \ rV 4.0' / 1 \ \ \ /'"'A \ 2,5 |!2.5 Conoj^ ,'-1.8. \ \ BoulevaiiiJ?-0 '^^-^-^^^^M^anos^ajaCaaomia Iguana County of San Diego Hydrology Manual Rainfall Isopluxnals 2 Year Rainfall Event - 24 Hou-s /V' Isopluvial (inches) Map Notes Stateplane Prq^tn. Zones, NAD83 Creation 0£«e: JUne 22.2001 mnO BE USED FOR DESIGN CALCUUTIONS 7.5 MLES amecP ^P>M>«J>>dnl)laliAicaiifafaaj.ail APPENDIX 2 PROPOSED CONDITIONS RATIONAL METHOD COMPUTER OUTPUT T:\Water Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\Appendix.DOC RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-2003 Advanced Engineering Software (aes) Ver. 1.5A Release Date: 01/01/2003 License ID 1509 Analysis prepared by: ProjectDesign Consultants 701 B Street, Suite 800 San Diego, CA 92101 619-235-6471 ************************** DESCRIPTION OF STUDY ************************** * 2407.30 - BRESSI RANCH * * PROPOSED CONDITIONS - OS-2 * * 100-YEAR STORM EVENT * ************************************************************************** FILE NAME: 2407-HOl.DAT TIME/DATE OF STUDY: 10:50 04/16/2004 USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: 1985 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.800 SPECIFIED MINIMUM PIPE SIZE(INCH) = 6.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: ONLY PEAK CONFLUENCE VALUES CONSIDERED *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) 1 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0313 0.167 0.0150 GLOBAL STREET FLOW-DEPTH CONSTRAINTS: 1. Relative Flow-Depth = 0.50 FEET as (Maximum Allowable Street Flow Depth) - (Top-of-Curb) 2. (Depth)*(Velocity) Constraint = 6.0 (FT*FT/S) *SIZE PIPE WITH A FLOW CAPACITY GREATER THAN OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.* **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 105.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< GRASS GOOD COVER RUNOFF COEFFICIENT = .4500 SOIL CLASSIFICATION IS "D" S.C.S. CURVE NUMBER (AMC II) = 80 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 372.70 DOWNSTREAM ELEVATION(FEET) = 369.20 ELEVATION DIFFERENCE(FEET) = 3.50 URBAN SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.3 82 *CAUTION: SUBAREA SLOPE EXCEEDS COUNTY NOMOGRAPH DEFINITION. EXTRAPOLATION OF NOMOGRAPH USED. TIME OF CONCENTRATION ASSUMED AS 6-MIN. 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.559 SUBAREA RUNOFF(CFS) = 0.24 TOTAL AREA(ACRES) = 0.08 TOTAL RUNOFF(CFS) = 0.24 **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 110.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 368.00 DOWNSTREAM(FEET) = 367.00 FLOW LENGTH(FEET) = 55.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 6.0 INCH PIPE IS 2.0 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 4.06 ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.24 PIPE TRAVEL TIME(MIN.) = 0.23 Tc{MIN.) = 6.23 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 110.00 = 120.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 110.00 TO NODE 110.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.404 *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.13 SUBAREA RUNOFF(CFS) = 0.46 TOTAL AREA(ACRES) = 0.21 TOTAL RUNOFF(CFS) = 0.69 TC(MIN.) = 6.23 **************************************************************************** FLOW PROCESS FROM NODE 110.00 TO NODE 115.00 IS CODE = 31 >>»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 3 67.00 DOWNSTREAM(FEET) = 355.00 FLOW LENGTH(FEET) = 62.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 6.0 INCH PIPE IS 1.9 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 12.80 ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.69 PIPE TRAVEL TIME(MIN.) = 0.08 Tc(MIN.) = 6.31 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 115.00 = 182.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 115.00 TO NODE 115.00 IS CODE = 81 »>»ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.351 *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.20 SUBAREA RUNOFF(CFS) = 0.70 TOTAL AREA(ACRES) = 0.41 TOTAL RUNOFF(CFS) = 1.39 TC(MIN.) = 6.31 **************************************************************************** FLOW PROCESS FROM NODE 115.00 TO NODE 120.00 IS CODE = 31 >»»COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 355.00 DOWNSTREAM(FEET) = 354.40 FLOW LENGTH(FEET) = 49.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 9.0 INCH PIPE IS 5.0 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 5.48 ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 1.39 PIPE TRAVEL TIME(MIN.) = 0.15 Tc(MIN.) = 6.46 LONGEST FLOWPATH FROM NODE 100.00 TO NODE 120.00 = 231.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 120.00 TO NODE 120.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) =6.46 RAINFALL INTENSITY(INCH/HR) = 6.26 TOTAL STREAM AREA(ACRES) = 0.41 PEAK FLOW RATE(CFS) AT CONFLUENCE = 1.39 **************************************************************************** FLOW PROCESS FROM NODE 125.00 TO NODE 130.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 80 INITIAL SUBAREA FLOW-LENGTH(FEET) = 283.00 UPSTREAM ELEVATION(FEET) = 361.00 DOWNSTREAM ELEVATION(FEET) = 355.80 ELEVATION DIFFERENCE(FEET) = 5.20 URBAN SUBAREA OVERLAND TIME OF FLOW(MIN.) = 13.598 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.869 SUBAREA RUNOFF(CFS) = 0.83 TOTAL AREA(ACRES) = 0.39 TOTAL RUNOFF(CFS) = 0.83 **************************************************************************** FLOW PROCESS FROM NODE 130.00 TO NODE 120.00 IS CODE = 31 >»»COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 354.50 DOWNSTREAM(FEET) = 354.40 FLOW LENGTH(FEET) = 24.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 9.0 INCH PIPE IS 5.1 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 3.20 ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.83 PIPE TRAVEL TIME(MIN.) = 0.12 Tc(MIN.) = 13.72 LONGEST FLOWPATH FROM NODE 12 5.00 TO NODE 120.00 = 307.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 120.00 TO NODE 120.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< >»»AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN. ) = 13.72 RAINFALL INTENSITY(INCH/HR) = 3.85 TOTAL STREAM AREA(ACRES) = 0.39 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.83 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 1.39 6.46 6.257 0.41 2 0.83 13.72 3.847 0.39 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 1.90 6.46 6.257 2 1.69 13.72 3.847 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 1.90 Tc(MIN.) = 6.46 TOTAL AREA(ACRES) = 0.80 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 120.00 = 307.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 120.00 TO NODE 135.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »>»USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 354.40 DOWNSTREAM(FEET) = 354.10 FLOW LENGTH(FEET) = 15.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 9.0 INCH PIPE IS 5.2 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 7.11 ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 1.90 PIPE TRAVEL TIME(MIN.) = 0.04 Tc(MIN.) = 6.49 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 135.00 = 322.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 135.00 TO NODE 135.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.235 GRASS GOOD COVER RUNOFF COEFFICIENT = .4500 SOIL CLASSIFICATION IS "D" S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.3 8 SUBAREA RUNOFF(CFS) = 1.07 TOTAL AREA(ACRES) = 1.18 TOTAL RUNOFF(CFS) = 2.97 TC(MIN.) = 6.49 **************************************************************************** FLOW PROCESS FROM NODE 135.00 TO NODE 140.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 354.10 DOWNSTREAM(FEET) = 352.50 FLOW LENGTH(FEET) = 41.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 9.0 INCH PIPE IS 5.6 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 10.19 ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 2.97 PIPE TRAVEL TIME(MIN.) = 0.07 Tc(MIN.) = 6.56 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 140.00 = 363.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 140.00 TO NODE 140.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.193 GRASS GOOD COVER RUNOFF COEFFICIENT = .4500 SOIL CLASSIFICATION IS "D" S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.3 5 SUBAREA RUNOFF(CFS) = 0.98 TOTAL AREA(ACRES) = 1.53 TOTAL RUNOFF(CFS) = 3.94 TC(MIN.) = 6.56 **************************************************************************** FLOW PROCESS FROM NODE 140.00 TO NODE 140.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) = 6.56 RAINFALL INTENSITY(INCH/HR) = 6.19 TOTAL STREAM AREA(ACRES) = 1.53 PEAK FLOW RATE(CFS) AT CONFLUENCE = 3.94 **************************************************************************** FLOW PROCESS FROM NODE 145.00 TO NODE 150.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< GRASS GOOD COVER RUNOFF COEFFICIENT = .4500 SOIL CLASSIFICATION IS "D" S.C.S. CURVE NUMBER (AMC II) = 80 INITIAL SUBAREA FLOW-LENGTH(FEET) = 166.00 UPSTREAM ELEVATION(FEET) = 3 60.00 DOWNSTREAM ELEVATION(FEET) = 353.70 ELEVATION DIFFERENCE(FEET) = 6.30 URBAN SUBAREA OVERLAND TIME OF FLOW(MIN.) = 9.665 *CAUTION: SUBAREA SLOPE EXCEEDS COUNTY NOMOGRAPH DEFINITION. EXTRAPOLATION OF NOMOGRAPH USED. 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.823 SUBAREA RUNOFF(CFS) = 0.15 TOTAL AREA(ACRES) = 0.07 TOTAL RUNOFF(CFS) = 0.15 **************************************************************************** FLOW PROCESS FROM NODE 150.00 TO NODE 190.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) ««< ELEVATION DATA: UPSTREAM(FEET) = 353.20 DOWNSTREAM(FEET) = 352.90 FLOW LENGTH(FEET) = 34.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 6.0 INCH PIPE IS 1.9 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 2.80 ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.15 PIPE TRAVEL TIME(MIN.) = 0.20 Tc(MIN.) = 9.87 LONGEST FLOWPATH FROM NODE 145.00 TO NODE 190.00 = 200.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 190.00 TO NODE 190.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.759 *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.04 SUBAREA RUNOFF(CFS) = 0.10 TOTAL AREA(ACRES) = 0.11 TOTAL RtJNOFF (CFS) = 0.26 TC(MIN.) = 9.87 ******************************************** FLOW PROCESS FROM NODE 190.00 TO NODE 140.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 352.90 DOWNSTREAM(FEET) = 352.50 FLOW LENGTH(FEET) = 37.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 6.0 INCH PIPE IS 2.4 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 3.44 ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.26 PIPE TRAVEL TIME(MIN.) = 0.18 Tc(MIN.) = 10.05 LONGEST FLOWPATH FROM NODE 145.00 TO NODE 140.00 = 237.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 140.00 TO NODE 140.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) = 10.05 RAINFALL INTENSITY(INCH/HR) = 4.70 TOTAL STREAM AREA(ACRES) = 0.11 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.26 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 3.94 6.56 6.193 1.53 2 0.26 10.05 4.704 0.11 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 4.14 6.56 6.193 2 3.25 10.05 4.704 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 4.14 Tc(MIN.) = 6.56 TOTAL AREA(ACRES) = 1.64 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 140.00 = 3 63.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 140.00 TO NODE 155.00 IS CODE = 31 >»»COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) ««< ELEVATION DATA: UPSTREAM(FEET) = 352.50 DOWNSTREAM(FEET) = 352.00 FLOW LENGTH(FEET) = 48.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 12.0 INCH PIPE IS 8.9 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 6.63 ESTIMATED PIPE DIAMETER(INCH) = 12.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 4.14 PIPE TRAVEL TIME(MIN.) = 0.12 Tc(MIN.) = 6.68 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 155.00 = 411.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 155.00 TO NODE 155.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.121 •*USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .7000 S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.26 SUBAREA RUNOFF(CFS) = 1.11 TOTAL AREA(ACRES) = 1.90 TOTAL RUNOFF(CFS) = 5.25 TC(MIN.) = 6.68 **************************************************************************** FLOW PROCESS FROM NODE 155.00 TO NODE 160.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 352.00 DOWNSTREAM(FEET) = 351.80 FLOW LENGTH(FEET) = 36.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 15.0 INCH PIPE IS 10.7 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 5.59 ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 5.25 PIPE TRAVEL TIME(MIN.) = 0.11 Tc(MIN.) = 6.79 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 160.00 = 447.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 160.00 TO NODE 160.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.058 *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .7000 S.C.S. CURVE NUMBER (AMC II) = 80 SUBAREA AREA(ACRES) = 0.06 SUBAREA RUNOFF(CFS) = 0.25 TOTAL AREA(ACRES) = 1.96 TOTAL RUNOFF(CFS) = 5.51 TC(MIN.) = 6.79 **************************************************************************** FLOW PROCESS FROM NODE 160.00 TO NODE 165.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) ««< ELEVATION DATA: UPSTREAM(FEET) = 351.80 DOWNSTREAM(FEET) = 350.90 FLOW LENGTH(FEET) = 68.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 15.0 INCH PIPE IS 8.2 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 7.98 ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 5.51 PIPE TRAVEL TIME(MIN.) = 0.14 Tc(MIN.) =6.93 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 165.00 = 515.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 165.00 TO NODE 165.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS =2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) = 6.93 RAINFALL INTENSITY(INCH/HR) = 5.98 TOTAL STREAM AREA(ACRES) = 1.96 PEAK FLOW RATE(CFS) AT CONFLUENCE = 5.51 **************************************************************************'*'* FLOW PROCESS FROM NODE 170.00 TO NODE 175.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< COMMERCIAL DEVELOPMENT RUNOFF COEFFICIENT = .8500 SOIL CLASSIFICATION IS "D" S.C.S. CURVE NUMBER (AMC II) = 92 INITIAL SUBAREA FLOW-LENGTH(FEET) = 135.00 UPSTREAM ELEVATION(FEET) = 360.00 DOWNSTREAM ELEVATION(FEET) = 359.00 ELEVATION DIFFERENCE(FEET) = 1.00 URBAN SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.779 TIME OF CONCENTRATION ASSUMED AS 6-MIN. 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.559 SUBAREA RUNOFF(CFS) = 1.00 TOTAL AREA(ACRES) = 0.18 TOTAL RUNOFF(CFS) = 1.00 **************************************************************************** FLOW PROCESS FROM NODE 175.00 TO NODE 165.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) ««< ELEVATION DATA: UPSTREAM(FEET) = 355.60 DOWNSTREAM(FEET) = 350.90 FLOW LENGTH(FEET) = 21.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 6.0 INCH PIPE IS 2.2 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 14.93 ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 1.00 PIPE TRAVEL TIME(MIN.) = 0.02 Tc(MIN.) = 6.02 LONGEST FLOWPATH FROM NODE 170.00 TO NODE 165.00 = 156.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 165.00 TO NODE 165.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES«<« TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) = 6.02 RAINFALL INTENSITY(INCH/HR) = 6.54 TOTAL STREAM AREA(ACRES) = 0.18 PEAK FLOW RATE(CFS) AT CONFLUENCE = 1.00 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 5.51 6.93 5.978 1.96 2 1.00 6.02 6.542 0.18 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 6.04 6.02 6.542 2 6.42 6.93 5.978 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 6.42 Tc(MIN.) = 6.93 TOTAL AREA(ACRES) = 2.14 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 165.00 = 515.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 165.00 TO NODE 180.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »>»USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 3 50.90 DOWNSTREAM(FEET) = 350.70 FLOW LENGTH(FEET) = 15.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 15.0 INCH PIPE IS 9.1 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 8.28 ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 6.42 PIPE TRAVEL TIME(MIN.) = 0.03 Tc(MIN.) = 6.96 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 180.00 = 530.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 180.00 TO NODE 180.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.961 *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .7000 S.C.S. CURVE NUMBER (AMC II) = 92 SUBAREA AREA(ACRES) = 0.05 SUBAREA RUNOFF(CFS) = 0.21 TOTAL AREA(ACRES) = 2.19 TOTAL RUNOFF(CFS) = 6.63 TC(MIN.) = 6.96 **************************************************************************** FLOW PROCESS FROM NODE 180.00 TO NODE 185.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ELEVATION DATA: UPSTREAM(FEET) = 350.70 DOWNSTREAM(FEET) = 338.40 FLOW LENGTH(FEET) = 181.00 MANNING'S N = 0.010 DEPTH OF FLOW IN 12.0 INCH PIPE IS 6.4 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 15.43 ESTIMATED PIPE DIAMETER(INCH) = 12.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 6.63 PIPE TRAVEL TIME(MIN.) = 0.20 Tc(MIN.) = 7.15 LONGEST FLOWPATH FROM NODE 125.00 TO NODE 185.00 = 711.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 185.00 TO NODE 185.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.856 *USER SPECIFIED(SUBAREA): RURAL DEVELOPMENT RUNOFF COEFFICIENT = .7000 S.C.S. CURVE NUMBER (AMC II) = 92 SUBAREA AREA(ACRES) = 0.37 SUBAREA RUNOFF(CFS) = 1.52 TOTAL AREA(ACRES) = 2.56 TOTAL RUNOFF(CFS) = 8.15 TC(MIN.) = 7.15 END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 2.56 TC(MIN.) = 7.15 PEAK FLOW RATE(CFS) = 8.15 END OF RATIONAL METHOD ANALYSIS APPENDIX 3 FLOWMASTER NORMAL DEPTH CALCULATIONS T:\Water Resources\2407.3-Bressi ResidentialVOpen Space 2\lst Submittal\Report\Appendix.DOC Wiley Way Catch Basin Pipe Worksheet for Circular Channel Project Description Worksheet Wiley Way Catch Row Element Circular Channel Method Manning's Formul Solve For Full Flow Capacity Input Data Mannings Coeffic 0.013 Slope 018000 ft/ft Diameter 18 In Results Depth 1.50 ft Discharge 14.09 cfs Flow Area 1.8 ft^ Wetted Perime 4.71 ft Top Width 0.00 ft Critical Depth 1.38 ft Percent Full 100.0 % Critical Slope 015608 ft/ft Velocity 7.97 ft/s Velocity Head 0.99 ft Specific Energ 2.49 ft Froude Numbe 0.00 Maximum Disc 15.16 cfs Discharge Full 14.09 cfs Slope Full 018000 ft/ft Flow Type N/A Project Engineer; Dick Isaac t:\...\1stsubmitta^exce^recreationalcenter.fm2 Project Design Consultants FlowMaster v6.1 [614o] 04/19/04 03:16:27 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203)755-1666 Pagelofi Dunham Avenue Worksheet for Circular Channel Project Description Worksheet Dunham Avenu Flow Element Circular Channt Method Manning's Fom Solve For Full Flow Capac Input Data Mannings Coeffic 0.013 Slope 060000 ft/ft Diameter 18 in Results Depth 1.50 ft Discharge 25.73 cfs Flow Area 1.8 ft^ Wetted Perime 4.71 ft Top Width 0.00 ft Critical Depth 1.49 ft Percent Full 100.0 % Critical Slope 055704 ft/ft Velocity 14.56 ft/s Velocity Head 3.29 ft Specific Energ: 4.79 ft Froude Numbe 0.00 Maximum Disc 27.68 cfs Discharge Full 25.73 cfs Slope Full 060000 ft/ft Flow Type N/A Project Engineer: Dick Isaac t:V..\1stsubmitta^exce^recreational center.fm2 Project Design Consultants FlowMaster v6.1 [614o] 04/19/04 03:56:09 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203)755-1666 Pagelofi EXHIBIT A PROPOSED CONDITIONS HYDROLOGY MAP T:\Water Resources\2407.3-Bressi Residential\Open Space 2\lst Submittal\Report\Appendix.DOC