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HomeMy WebLinkAboutWater System Analysisop- 0 I Y/ Hester Engineering Company Civil Engineering Services 7607 Eastmark Drive, Suite 253 -B College Station, Texas 77840 Ph: 979 -693 -1100 Email: mhester @hester - engr.com January 26, 2004 Mr. Spencer Thompson College Station Engineering Division P.O. Box 9960 College Station, TX 77842 979 - 764 -3570 Re: Southern Trace Subdivision Water Distribution System Analysis Supplement to Original WDSA OF ♦.•M•••M M••••NNH�•y. MICHAEL G. HESTER ��MMl MM •.K� �•��4 Ra Dear Spencer, I ' Per your request attached is a water system model of the existing conditions and the proposed Southern Trace Subdivision. The proposed system will connect to an existing 8" waterline at the end of Oldenburg Lane in the Edelwiess Gartens Subdivision. Static pressure information was obtained from the College Station Utility Department and was based on an onsite pressure tests of fire hydrants located in the Edelweiss Gartens subdivision. The flow test reports are included in the original WDSA. The. proposed subdivision was modeled using the Haestead Methods ' WaterCad" program placing fire flow demands at each node in the system, see attached schematic. The maximum daily demand generated by the dwelling units is added to the fire flow demand. The results of the analysis has been included in this report. ANALYSIS REQUIREMENTS / CONSTRAINTS -PVC water line pipe with a roughness coefficient of 150 -Fire flows of 1500 gpm (gallons per minute) -8 -inch minimum waterline size - Minimum residual pressures at 20 psi (pounds per square inch) Velocities below 12 fps (feet per second) DAILY FLOW CALCULATIONS RESIDENTIAL (1 D.U.) *(2.67 PEOPLE /D.U.) *(100 GPCD) *(1 DAY/ 1440 MIN.)= 0.19 GPM Average Daily Flow * 1.5 = Adjusted Daily Flow Adjusted Daily Flow * 3.0 = Peak Hourly Flow Maximum daily flow for a section of waterline = 0.86 gpm times the number of lots. COMMERCI (ACRES)* (30 PEOPLE / ACRE)* (50 GPCD)* (1DAY/1440 MIN) = 1.04 GPM* 1.5* 3 =4.7 GPM CONCLUSION: In conclusion the proposed system can provide a fireflow demand of 1500 gpm at each fire hydrant with a residual pressure greater than 20 psi. Scenario: Base R -1 SOUTHERN TRACE SUBDIVISION WATER DISTRIBUTION SYSTEM ANALYSIS SEPTEMBER 25,2003 BOJ -11 FH J5 Title: Southern Trace Subdivision Project Engineer: Michael G. Hester, P.E. d: \haestad \wtr,lsouthertrace.wcd NESTER ENGINEERING COMPANY WaterCAD v4.1.1 [4.2014] 01/25/04 03:09:09 PM ©Haestad Methods, Inc. 37 Brookside Road Waterbury, CT06708 USA +1- 203 - 755 -1666 Page 1 of 1 Scenario: Base Fire Flow Analysis Pipe Report Label Diameter (in) Length (ft) Material Hazen- Williams C Minor Loss Coefficient Discharge (gpm) Velocity (ftts) P -2 ENCASEC ACROSS SH40 8.0 667.00 PVC 150.0 2.06 40.06 0.26 P -3 8.0 155.00 PVC 150.0 0.54 40.06 0.26 P-4 8.0 392.00 PVC 150.0 1.67 15.85 0.10 P -5 ALONG WELLBORN ROAD 8.0 562.00 PVC 150.0 1.94 6.67 0.04 P-6 6.0 125.00 PVC 150.0 0.35 0.00 0.00 P -7 8.0 144.00 PVC 150.0 1.67 6.67 0.04 P-8 8.0 852.00 PVC 150.0 0.35 3.33 0.02 P -9 8.0 158.00 PVC 150.0 0.74 -15.86 0.10 P -10 8.0 188.00 PVC 150.0 2.08 -22.54 0.14 P -11 SOUTHERN BREEZE 8.0 196.00 PVC 150.0 2.52 0.00 0.00 P -1 EXISTING 8" ALONG OLDENBURG 8.01 720.001 PVC 1 150.01 2.471 56.711 0.36 Title: Southern -race Subdivision Project Engineer: Michael G. Hester, P.E. d: \haestad \wtr,`.southertrace.wcd HESTER ENGINEERING COMPANY WaterCAD v4.1.1 [4.2014] 01/26/04 03:08:44 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1 -203- 755 -1666 Page 1 of 1 Scenario: Base Fire Flow Analysis Junction Report Label Elevation (ft) Demand (gpm) Available Fire Flow (gpm) Residual Pressure (psi) Calculated Minimum System Pressure (psi) Calculated Residual Pressure (psi) Pressure (psi) Fire Flow Balanced? TEE J -2 v 323.20 16.65 1,750.00 20.00 59.41 70.15 85.45 true J -3 BENDS 335.20 0.00 1,750.00 20.00 45.67 51.21 80.25 true TEE J-4 338.50 1.67 1,750.00 20.00 42.42 46.53 78.82 true FH J -5 333.00 9.18 1,750.00 20.00 41.47 44.71 81.19 true TEE J-6 336.00 0.00 1,750.00 20.00 39.14 41.30 79.90 true BO J -7 341.00 0.00 1,750.00 20.00 40.44 29.49 77.73 true FH J-8 338.00 3.34 1,750.00 20.00 40.04 40.29 79.03 true FH J -9 348.00 19.19 1,750.00 20.00 41.80 38.13 74.71 true J -10 343.00 6.68 1,750.00 20.00 39.61 41.56 76.87 true BO J -11 1 343.501 0.001 1,750.001 20.001 39.611 35.861 76.651 true Title: Southern - 'race Subdivision Project Engineer: Michael G. Hester, P.E. d: \haestad \wtr --'.southertrace.wcd HESTER ENGINEERING COMPANY WaterCAD v4.1.1 ]4.2014] 01/26/04 03:08.05 PM ©Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1 -203- 755 -1666 Page 1 of 1