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Home My WebLink AboutCDP 01-47; Nayudu Residence; Hydrology and Hydraulic Report; 2002-01-02HYDROLOGY & HYDRAULIC REPORT NAYUDU RESIDENCE 3286 LINCOLN ST. CARLSBAD,CA 92008 PREPARED FOR: KRIS & NANCY NAYUDU DATE: 01/02/2002 PE 856F 1 l/ll lov PREPARED BY: PASCO ENGINEERING, INC. 535 NORTH HWY. 101, SUITE A SOLANABEACH, CA. 92075 C^yU^/'(:j^X^ WAYNE A. PASCO, RCE 29577 A. INTRODUCTION The purpose ofthis report is to provide 100 year storm hydrology calculations for a proposed single family residence. Also included are capacity calculations for area drains and PVC piping as shown on the grading plan. The 0.17 acre site is physicaUy located at 3286 Lincoln Street in Carlsbad, CA (Nayudu Residence). It is geographicaUy located at 33°09'20" North Latitude and 117°20'50" West Longitude. Based on the hydrologic data contained within this report, a system can be constructed to adequately intercept, contain and convey Qioo to the discharge points noted on the Hydrology Map. B. DISCUSSION Based on the USCS Soil Maps the hydrologic soil classification for the site was determined to be type "A". The methodology used herein to determine Qioo is rational method. The program utilized is by Advanced Engineering Software (AES). Please refer to Section D for Qioo calculations and other hydrology references. Section E contains hydraulic calculations and the Hydrology Map can be found in Section F. C. CONCLUSION Based on the calculations contained in this report it is the professiorial opinion of Pasco Engineering that a system can be constructed to adequately intercept, contain and convey Qioo to the discharge points noted on the Hydrology Map. D. HYDROLOGY CALCULATIONS ****************** + ***** + **********•**********-**•*•**-**********•**************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-92 Advanced Engineering Software (aes) Ver. 1.3A Release Date: 3/06/92 License ID 1388 Analysis prepared by: Pasco Engineering, Inc. 535 North Highway 101 Suite A Solana Beach, CA 92075 (858)259-8212 ************************** DESCRIPTION OF STUDY **************************** * Nayudu Residence Hydrology Study * * * ^****************** ****************************************-***-»•********•*•*-* FILE NAME: 856.DAT TIME/DATE OF STUDY: 12: 4 1/ 2/2002 USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: 1985 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.600 SPECIFIED MINIMUM PIPE SIZE(INCH) = 3.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = .95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED NOTE: ONLY PEAK CONFLUENCE VALUES CONSIDERED j^^jt.j.jnr*****************************************************-*-******-*******'*** FLOW PROCESS FROM NODE 1.10 TO NODE 1.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< SOIL CLASSIFICATION IS "A" / ' \^ ^ . SINGLE FAMILY DEVELOPMENT RUNOFF COEFFICIENT =( .4000 J-^ [AfCLt/P^ ^ yfi;UV^ /f\i INITIAL SUBAREA FLOW-LENGTH = 82.00 ^ y UPSTREAM ELEVATION = 51.70 '/ //J fLSfOtJi DOWNSTREAM ELEVATION = 50.83 ELEVATION DIFFERENCE = .87 URBAN SUBAREA OVERLAND TIME OF FLOW(MINUTES) = 11. 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.075 SUBAREA RUNOFF(CFS) = .08 TOTAL AREA(ACRES) = -05 TOTAL RUNOFF(CFS) = .08 ****************************************-»^*-********************************** FLOW PROCESS FROM NODE 1.10 TO NODE 2.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<«« SOIL CLASSIFICATION IS "A" SINGLE FAMILY DEVELOPMENT RUNOFF COEFFICIENT = .4000 INITIAL SUBAREA FLOW-LENGTH = 80.00 UPSTREAM ELEVATION = 51.70 DOWNSTREAM ELEVATION = 50.90 ELEVATION DIFFERENCE = .80 URBAN SUBAREA OVERLAND TIME OF FLOW(MINUTES) = 11.270 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.056 SUBAREA RUNOFF(CFS) = .07 TOTAL AREA(ACRES) = .04 TOTAL RUNOFF(CFS) = .07 ******* ***********************************-********************************** FLOW PROCESS FROM NODE 3.10 TO NODE 3.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< SOIL CLASSIFICATION IS "A" SINGLE FAMILY DEVELOPMENT RUNOFF COEFFICIENT = .4000 INITIAL SUBAREA FLOW-LENGTH = 30.00 UPSTREAM ELEVATION = 51.90 DOWNSTREAM ELEVATION = 50.4 0 ELEVATION DIFFERENCE = 1.50 URBAN SUBAREA OVERLAND TIME OF FLOW(MINUTES) = 4.036 *CAUTION: SUBAREA SLOPE EXCEEDS COUNTY NOMOGRAPH DEFINITION. EXTRAPOLATION OF NOMOGRAPH USED. TIME OF CONCENTRATION ASSUMED AS 5-MINUTES 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.850 SUBAREA RUNOFF(CFS) = .19 TOTAL AREA (ACRES) =. .07 TOTAL RUNOFF (CFS)^^= ^19 END OF STUDY SUMMARY: PEAK FLOW RATE(CFS).= .19 Tc(MIN.) = 5.00 TOTAL AREA(ACRES) = .07 END OF RATIONAL METHOD ANALYSIS COUffTY OF SAN DIEGO DEPARTMENT OF SANITATION & FLOOD CONTROL 100-YEAR 8-H0y^ PRECIPITATlOi^ ISOPLUVIALS PnECIFITATiOri m OF 100-YEAR 6-HOUR nmis OF Art li^Gii 33' PrcpA U.S. DEPARTMEN V OF COMMERCE UATIOUAL OCEANIC AND AT>]oSPllEKIC ADMINISTRATION SPECIAL STUDIES BRANCH, OFFICE OF II 30'. { COUNTY OF SAN DIEGO DEPARTMENT OF SANITATION S. FLOOD CONTROL 33' 30' 15' li5' U.S. DEPARTMEN NATIONAL OCUAMC ANO AT: SPECIAL STUDIES UKANCII. OKKICE OF II ( 100-YEAR 24-HOljR PRECIPITATION ^20-^ ISOPLUVIALS OF 100 -YEAR 24-llOUR PRECIPITATIOM IM EMTIIS OF AN IfJCH 30' I nil" 116" . ( INTENSITY-DURATION DESIGN CHART March 1982 ~n '"T^iTriTllHiltil 11 '•' m'lliiiuiiai.iiumtr:. . . V i i.i-i.i Li ininirlm Equation: I - 7.44 D • Intensity (In./Hr.) ' 6 Hr. Precipitation (In.) « Duration (Min.) 15 20 Directions for Application: 1) From precipitation naps determine 6 hr. and 24 hr. amounts for the selected frequency. These maps are printed 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. (Kot applicable 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: 0) Selected Frequency loo 1) Pfi =2'(D in.. P 2) Adjusted *Pg= 24 yr. Pg = S(o %* P24 In. 3) 4) I =• min. in/hr. *Not Applicable to Desert Region APPENDIX XI IV-A-14 Table 3-1 RUNOFF COEFFICIENTS FOR URBAN AREAS Land Use Runoff Coefficient "C Soil Type NRCS Elements County Elements % IMPER. A B C D^ Undisturbed Natural Terrain Pennanent Open Space 0* 0.20 0.25 0.30 0.35 Low Residential, 1.0 DU/A or less 10 0.27 0.32 0.36 0.41 Low Residential, 2.0 DU/A or less 20 0.34 0.38 0.42 0.46 Low Residential, 2.9 DU/A or less <2S 0.38 0.41 0.45 0.49 Medium Density Residential Residential, 4.3 DU/A or less 30 0.41 0.45 0.48 0.52 Medium Density Residential Residential, 7.3 DU/A or less 40 0.48 0.51 0.54 "075T Medium Density Residential Residential, 10.9 DU/A or less 45 0.52 0.54 0.57 0.60 Medium Density Residential Residential, 14.5 DU/A or less 50 0.55 0.58 0.60 0.63 High Density Residential Residential, 24.0 DU/A or less 65 0.66 0.67 0.69 0.71 High Density Residential Residential, 43.0 DU/A or less 80 0.76 0.77 0.78 0.79 Commercial/Industrial Neighborhood Commercial 80 0.76 0.77 0.78 0.79 Commercial/Industrial General Commercial 85 0.80 0.80 0.81 0.82 Commercial/Industrial Office Professional/Commercial 90 0.83 0.84 0.84 0.85 Commercial/Industrial Limited Industrial 90 0.83 0.84 0.84 0.85 Commercial/Industrial General Industrial 95 fl^.^-7 0^ 0.95 e^.l *The values associated with 0% impervious may be used for direct calculation of the runoff coefficient as described runoff coefficient, Cp, for the soil type), or for areas that will remain undisturbed in perpetuity. Justification must forever (e.g., the area is located in Cleveland National Forest). DU/A = dwelling units per acre NRCS = National Resources Conservation Service in Section 3.1.2 (representing the pervious be given that tlie area will remain natural TABLE 11.—INTERPRETATIONS FOR LAND MANAGEMENT--Continued Map synribol Soil Hydro- logic group Erodibility Limitations for conversion from brush to grass LfE LpB LpC LpC2 LpD2 LpE2 LrE LrE2 LrG LsE LsF Lu LvF3 Md MlC MIE MnA MnB MoA MpA2 MrG MvA MvC MvD MxA OhC GhE OhF OkC OkE PeA PeC PeC2 PeD2 PfA PfC Py Las Flores-Urban land complex, 9 to 30 percent slopes: Las Flores Urban land Las Posas fine sandy loam, 2 to 5 percent slopes to 9 percent slopes- to 9 percent slopes. to IS percent slopes, 15 to 30 percent slopes, 9 to 30 percent 9 to 30 percent 30 to 65 percent Las Posas fine sandy loam. Las Posas fine sandy loam, eroded. Las Posas fine sandy loam, eroded. Las Posas fine sandy loam, eroded. Las Posas stony fine sandy loam, slopes. Las Posas stony fine sandy loam, slopes, eroded. Las Posas stony fine sandy loam, slopes. Linne clay loam, 9 to 30 percent slopes Linne clay loam, 30 to 50 percent slopes- Loamy alluvial land • Loamy alluvial land-Huerhuero complex, 9 to 50 percent slopes, severely eroded: Loamy alluvial land Huerhuero Hade land )4arina loamy coarse sand, 2 to 9 percent slopes Carina loamy coarse sand, 9 to 30 percent slopes Mecca coarse sandy loam, 0 to 2 percent slopes Mecca coarse sandy loam, 2 to 5 percent slopes Mecca sandy loam, saline, 0 to 2 percent slopes Mecca fine sandy loam, 0 to 2 percent slopes, eroded— Metamorphic roclc land Mottsville loamy coarse sand, 0 to 2 percent slopes Mottsville loamy coarse sand, 2 to 9 percent slopes Mottsville loamy coarse sand, 9 to 15 percent slopes— Mottsville loamy coarse sand, wet, 0 to 2 percent slopes. Olivenhain cobbly loam, 2 to 9 percent slopes Olivenhain cobbly loam, 9 to 30 percent slopes Olivenhain cobbly loam, 30 to 50 percent slopes Olivenhain-Urban land complex, 2 to 9 percent slopes: Olivenhain Urban land — Olivenhain-Urban land complex, 9 to 30 percent slopes: Olivenhain Urban land Placentia sandy loam, 0 to 2 percent slopes Placentia sandy loam, 2 to 9 percent slopes Placentia sandy loam, 5 to 9 percent slopes, eroded Placentia sandy loam, 9 to 15 percent slopes, eroded-— Placentia sandy loam, thick surface, 0 to 2 percent slopes. Placentia sandy loam, thick surface, 2 to 9 percent slopes. Playas D D D D D D D D D D C C B D D D A A B B B B D A A A D D D D D D D D D D 0 D D D D Moderate 2- Moderate 2- Moderate 2- Moderate 2- Moderate 1- Moderate 1- Moderate 1- Severe 1— Moderate 2- Severe 1— Severe 16— Severe 1 — Severe 1— Severe 2— Severe 2— Severe 16 Severe 16 Severe 16 Severe 16 Severe 1— Severe 2— Severe 2— Severe 2— Severe 2— Severe 16— Severe 16— Severe 1— Severe 9— Severe 9— Severe 9— Severe 9— Severe 16-- Severe 16— Moderate 2 Slight. Sli5»t. Slight. Slight. Slight. Moderate. Moderate. Moderate. Moderate. Moderate. Slight. Severe. Severe. Slight. Slight. Severe. Slight. £/ Slight. 4/ Slight. 4/ Slight. £/ Slight. Slight. Moderate. Slight. Slight. Slight. Slight. Slight. Slight. See footnotes at end of table. 36 E. HYDRAULIC CALCULATIONS Nayudu Residence Hydraulic Calculations Area Drain Calculations CALCULATE CAPACITY OF 12"x12'' AREA DRAIN W/ 2" OF AVAILABLE HEAD FORMULA: Qcap = 3.0(P)(D*1.5) / 3. DIVISION BY 3 ACCOUNTS FOR GRATE & REASONABLE BLOCKAGE. PERIMETER AVAIL HW GRATE FACTOR QIOO (CFS) P(FT) D(FT) 3' CAPACITY (CFS) INLET TYPE 0.08. 4 0.2 0.36 12"x 12" AREA DRAIN 3" PVC CAPACITY Cross Section for Circular Channel Project File c:\haestad\academic\fmw\856.fm2 Worksheet Nayudu Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Section Data Mannings Coefficient Channel Slope Depth Diameter Disdiarge 0.009 0.010000 ft/ft 0.14 ft 3.00 in 0.08 cfs 3.00 in H 1 NTS 01/02/02 12:06:23 PM Academic Ed-|tion Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FlowMaster v5.17 Page 1 of 1 F. HYDROLOGY MAP