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Home My WebLink AboutFire Flow Analysis B Bleyl & Associates 1722 Broadmoor Suite 210 (7L Planning . Engineering • Management Bryan. Texas 77802 A Ter. Reg. ,VO. F-678 February 25,2015 Matthew Brown Project Manager The Ben Brown Group RE: Sterling Heights Fire Flow Analysis Mr. Brown, As requested the fire flow capacity from the existing City of College Station 6" AC waterline on the north side of Sterling Street to the proposed Sterling Heights development has been analyzed. The subject tract is located on 218 Sterling Street in College Station approximately two blocks south of Holleman on the east side of Texas Avenue. A fire flow test was completed by the City of College Station on a fire hydrant located adjacent the property at 211 Sterling Street. This fire hydrant is known as FF1 (E-151) under the City of College Station nomenclature. Fire Hydrant (E-012) was also analyzed during this flow test for static and residual pressures while FI-i (E.-151) was flowed. The fire hydrant flow test is summarized in Table 1 below as well as attached for your reference. Table 1: Fire Hydrant Flow Test FH(E-151) FH (E-012) Flow(gpm) 1,455 NA Pilot reading(psi) 70 NA Static pressure (psi) NA 100 Residual pressure (psi) NA 94 The existing City of College Station waterline was modeled in Bentley \VaterCad V8i to determine the available amount of fire flow to the proposed development. A schematic layout of the model is attached for your reference. The first step in the modeling process was to calibrate the model to accurately represent the flows and pressures determined during the fire flow test. First the model was set up to have a static pressure in the system of 100 psi as determined in the fire flow test. The approximate elevation of the existing line at this location is 300'. A pressure head of 531' was assigned to the reservoir, "R-1", serving our model. This difference in pressure head is 231'or exactly 100psi.A reservoir was used to recreate the static pressure found in FH (E-112) simplifying the model to avoid recreating the system upstream of our area of concern. R-1 represents pressures served by the City of College Station water system. The second calibration was done was to ensure that FH-(E-151) was left with a pressure of 70psi when flowing at 1,455gpm. This was completed by assigning a calculated length to P-1, the pipe connecting "R-1" and FH-(E-151). This calculated length created the head loss required to decrease the pressure in FH-(E-151) to 70 psi when flowing at 1,455gpm. This length, although arbitrary in itself, represents the headloss determined in the City of College Station fire flow test through the existing piping, bends, etc. thus simplifying the model. Bryan Austin Conroe (979) 268-1125 (512) 328-7878 (936) 441-7833 (979) 260-3849 Fax (512) 328-7884 Fax (936) 760-3833 Fax once the model was calibrated three fire flow scenarios were completed. The results of all three scenarios are summarized in Table 2 below. Table 2: Fire Flow Analysis Construction Building IBC Fire Fire Flow Fire Sprinkler Peak Residential Type Area(SF) Area(SF) (gpm) Demand(gpm) Demand(gpm) Ultimate fire flow V-B 28,861 NA 2,280 180 17.8 Single unit/no fire V-B 28,861 28,861 2,250 180 17.8 wall required Split unit/one fire V-B 28,861 <15,600 1,750 180 17.8 wall required >18,000 P-1 flow/avg velocity(') P-2 flow/avg velocity Pressure in Pressure @ Sterling (gpm)/(ft/sec) (gpm)/(ft/sec) FH(E-151) Heights (psi) Existing 6"AC line Prop 4"Service Static Test 0/0 0/0 100 100 Fire Flow Test 1,455/8.26 0/0 70 70 Ultimate fire flow 2,478/14.06 198/5.05 21 20 Single unit/no fire 2,448/13.89 198/5.05 22 22 wall required Split unit/one fire 1,948/11.05 198/5.05 49 49 wall required Notes: (1) The average velocities were determined by taking the velocity in P-1 and dividing it by two. Currently the Bleyl & Associates model only feeds FH(E-151) from one direction. This assumption was made knowing that the actual distribution system feeds FH(E-151) from both directions creating a looping system. The flow was assumed to be fed evenly from both side of the distribution system in fire flow conditions thus decreasing the velocity in each supply pipe by half. The BCS Unified Guidelines limit velocities in a main to 12ft/sec under fire flow conditions.The maximum velocity may be increased on a case by case basis. The first scenario was "Ultimate Fire Flow" and analyzed the maximum fire flow that could be harnessed from the existing line. Under TCEQ rule 290.46(r) a minimum pressure of 20 psi is required during fire flow conditions. This requirement is also adhered to by the BCS Unified Guidelines. It was determined that a maximum fire flow of 2,280 gpm could be pulled from FH (E-151) and maintain 20psi in the distribution system. This fire flow scenario also took into account the peak residential demand of 17.8gpm and the fire sprinkler demand of 180 gpm. The second scenario analyzed was the development as a single unit with up, fire walls. The proposed apartments are a 28,861 SF Type V-B construction development. Under the International Building Code (IBC) a Type V-B construction area between 26,301 SF-29,300SF requires 4,500gpm of fire protection. Since this development will include fire protection sprinklers the required fire flow can be reduced by 50% to 2,250gpm. Under a fire flow analysis of 2,250gpm, including residential and fire sprinkler demand, a minimum pressure of 22psi was maintained at FH (E-151) and the proposed Sterling Heights development. The third scenario analyzed was the development as a "double" unit with one fire wall. As previously stated the proposed apartments are a 28,861 SF Type V-B construction development. Under the International Building Code (IBC) a Type V-B construction area between 15,601SF-18,000SF requires 3,500gpm of fire protection. Since this development will include fire protection sprinklers the required fire flow can be reduced by 50%to 1,750gpm. Under a fire flow analysis of 1,750 gpm,including residential and fire sprinkler demand, a minimum pressure of 49 psi was maintained at FH(E-151) and the proposed Sterling Heights development. To summarize, the analysis proves that if the building is constructed as proposed with 28,861SF, Type V-B construction, 17.8pgm maximum residential demand, and 180gpm fire sprinkler demand that no fire wall will be required to meet fire flow regulations. Under these conditions 2,250 gpm of fire flow will be required which would leave a pressure of 22psi in the distribution system. Under this flow scenario the velocity in the existing 6" main would be 13.89ft/sec which is 1.89ft/sec above the 12ft/sec limit. A discussion would be required with the City to see if this velocity would be accepted. If a fire wall is considered and 1,750gpm is used a pressure of 49gpm would be left in the distribution system. Under this flow scenario the velocity in the existing main would be 11.05 ft/sec. Sincerely (:). aeA *:avid L.Besly,P.E. fD81:8.713ESL.Y..41,::::*1 Project ManagerBleyl&Associates j •.• F-678 o‘�S�oAiAS 2- 2- �5' Scenario: Fire Flow Calibration FH-(E-151) P-1 R-1 w Sterling Heights Bentley Systems,Inc. Haestad Methods Solution Bentley WaterCAD V8i(SELECTseries 5) Sterling Heights Fire Flow.wtg Center [08 11 05.611 2/25/2015 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1686 College Station Utilities lw Reliable, Affordable, Community Owned Date test completed Thursday, February 19, 2015 Time completed 2;00 Test completed by JUSIN Witness HOWARD FLOW HYDRANT Location 221 STERLING, Nozzle size 2.5 Hydrant number E-151 Pitot reading in PSI 70 Flow in G P M 1455 STATIC HYDRANT Location 311 STERLING Hydrant number E-012 Static PSI 100 Residual PSI 94 Comments REQUESTED B Bleyl & Associates 1722 Broadmoor Suite 210 Planning • Engineering • Management Bryan. Texas 77802 A Ter. Reg. No. F-678 tit February 25,2015 Matthew Brown Project Manager The Ben Brown Group RE: Sterling Heights Fire Flow Analysis Mr.Brown, As requested the fire flow capacity from the existing City of College Station 6" AC waterline on the north side of Sterling Street to the proposed Sterling Heights development has been analyzed. The subject tract is located on 218 Sterling Street in College Station approximately two blocks south of Holleman on the east side of Texas Avenue. A fire flow test was completed by the City of College Station on a fire hydrant located adjacent the property at 211 Sterling Street. This fire hydrant is known as FH (E-151) under the City of College Station nomenclature. Fire Hydrant (E-012) was also analyzed during this flow test for static and residual pressures while FH (E-151) was flowed.The fire hydrant flow test is summarized in Table 1 below as well as attached for your reference. Table 1: Fire Hydrant Flow Test FH(E-151) FH(E-012) Flow(gpm) 1,455 NA Pilot reading(psi) 70 NA Static pressure(psi) NA 100 Residual pressure(psi) NA 94 The existing City of College Station waterline was modeled in Bentley WaterCad V8i to determine the available amount of fire flow to the proposed development. A schematic layout of the model is attached for your reference. The first step in the modeling process was to calibrate the model to accurately represent the flows and pressures determined during the fire flow test. First the model was set up to have a static pressure in the system of 100 psi as determined in the fire flow test. The approximate elevation of the existing line at this location is 300'. A pressure head of 531' was assigned to the reservoir, "R-1", serving our model. This difference in pressure head is 231'or exactly 100psi.A reservoir was used to recreate the static pressure found in FH (E-112) simplifying the model to avoid recreating the system upstream of our area of concern. R-1 represents pressures served by the City of College Station water system. The second calibration was done was to ensure that FH-(E-151) was left with a pressure of 70psi when flowing at 1,455gpm. This was completed by assigning a calculated length to P-1, the pipe connecting"R-1" and FH-(E-151).This calculated length created the head loss required to decrease the pressure in FH-(E-151) to 70 psi when flowing at 1,455gpm. This length, although arbitrary in itself, represents the headloss determined in the City of College Station fire flow test through the existing piping, bends, etc. thus simplifying the model. Bryan Austin Conroe (979) 268-1125 (512) 328-7878 (936) 441-7833 (979) 260-3849 Fax (512) 328-7884 Fax (936) 760-3833 Fax Once the model was calibrated three Eire flow scenarios were completed. The results of all three scenarios are summarized in Table 2 below. Table 2:Fire Flow Analysis Construction Building IBC Fire Fire Flow Fire Sprinkler Peak Residential Type Area(SF) Area(SF) (gpm) Demand(gpm) Demand(gpm) Ultimate fire flow V-B 28,861 NA 2,280 180 17.8 Single unit/no fire V-B 28,861 28,861 2,250 180 17.8 wall required Split unit/one fire V-B 28,861 <15,600 1,750 180 17.8 wall required >18,000 P-1 flow/avg velocity(') P-2 flow/avg velocity Pressure in Pressure @ Sterling (gpm)/(ft/sec) (gpm)/(ft/sec) FH(E-151) Heights(psi) Existing 6"AC line Prop 4"Service Static Test 0/0 0/0 100 100 Fire Flow Test 1,455/8.26 0/0 70 70 Ultimate fire flow 2,478/14.06 198/5.05 21 20 Single unit/no fire 2,448/13.89 198/5.05 22 22 wall required Split unit/one fire 1,948/11.05 198/5.05 49 49 wall required Notes: (1) The average velocities were determined by taking the velocity in P-1 and dividing it by two.Currently the Bleyl & Associates model only feeds FH(E-151) from one direction. This assumption was made knowing that the actual distribution system feeds FH(E-151) from both directions creating a looping system. The flow was assumed to be fed evenly from both side of the distribution system in fire flow conditions thus decreasing the velocity in each supply pipe by half. The BCS Unified Guidelines limit velocities in a main to 12ft/sec under fire flow conditions.The maximum velocity may be increased on a case by case basis. The first scenario was "Ultimate Fire Flow" and analyzed the maximum fire flow that could be harnessed from the existing line. Under TCEQ rule 290.46(r) a minimum pressure of 20 psi is required during fire flow conditions. This requirement is also adhered to by the BCS Unified Guidelines. It was determined that a maximum fire flow of 2,280 gpm could be pulled from FH (E-151) and maintain 20psi in the distribution system. This fire flow scenario also took into account the peak residential demand of 17.8gpm and the fire sprinkler demand of 180 gpm. The second scenario analyzed was the development as a single unit with no fire walls. The proposed apartments are a 28,861 SF Type V-B construction development. Under the International Building Code (IBC) a Type V-B construction area between 26,301SF-29,300SF requires 4,500gpm of fire protection. Since this development will include fire protection sprinklers the required fire flow can be reduced by 50% to 2,250gpm. Under a fire flow analysis of 2,250gpm, including residential and fire sprinkler demand, a minimum pressure of 22psi was maintained at FH (E-151) and the proposed Sterling Heights development. The third scenario analyzed was the development as a "double" unit with one fire wall. As previously stated the proposed apartments are a 28,861 SF Type V-B construction development. Under the International Building Code (IBC) a Type V-B construction area between 15,601SF-I8,000SF requires 3,500gpm of fire protection.Since this development will include fire protection sprinklers the required fire flow can be reduced by 50% to 1,750gpm. Under a fire flow analysis of 1,750 gpm,including residential and fire sprinkler demand, a minimum pressure of 49 psi was maintained at FH(E-151) and the proposed Sterling Heights development. To summarize, the analysis proves that if the building is constructed as proposed with 28,861SF, Type V-B construction, 17.8pgm maximum residential demand,and 180gpm fire sprinkler demand that no fire wall will be required to meet fire flow regulations. Under these conditions 2,250 gpm of fire flow will be required which would leave a pressure of 22psi in the distribution system. Under this flow scenario the velocity in the existing 6" main would be 13.89ft/sec which is 1.89ft/sec above the 12ft/sec limit. A discussion would be required with the City to see if this velocity would be accepted. If a fire wall is considered and 1,750gpm is used a pressure of 49gpm would be left in the distribution system. Under this flow scenario the velocity in the existing main would be 11.05 ft/sec. Sincerely h • ys1�i David L.Besly,P.E. j DAVID L. BESLY i Project Manager ��j 9 81873 'Q� Bleyl&Associates F-678 ,. ..'�!CENSSC?•'. �? %Sez5-- - c Scenario: Fire Flow Calibration FH-(E-151) P-1 R-1 i d Sterling Heights Bentley Systems,Inc. Haestad Methods Solution Bentley WaterCAD V8i(SELECTseries 5) Sterling Heights Fire Flow wtg Center 108.11.05.61] 2/25/2015 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1.203-755-1688 College Station Utilities Reliable,Affordable, Community Owned Date test completed Thursday, February 19, 2015 Time completed 2.00 Test completed by JUSIN Witness HOWARD FLOW HYDRANT Location 221 STERLING Nozzle size 2.5 Hydrant number E-151 Pitot reading in PSI 70 Flow in G P M 1455 STATIC HYDRANT Location 311 STERLING Hydrant number E-012 Static PSI 100 Residual PSI 94 Comments REQUESTED Sterling Heights Apartment Public Water Line Cost Estimate Item Qty Unit Description Unit Cost Total Furnish and install 4-inch PVC (C-900) water line, 1 275 LF including all fittings, excavation, embedment, and $ 25.00 $ 6,875.00 trench backfill as per the plans and specifications, complete and in place Furnish and install 4" MJ gate valve and box as per 2 2 EA the plans and specifications, complete and in place $ 500.00 $ 1,000.00 Furnish and install 2" MJ gate valve and box as per 3 1 EA the plans and specifications, complete and in place $ 300.00 $ 300.00 Furnish and install 6"X4" MJ tee including all blocking 4 1 EA and restraint as per the plans and specifications, $ 400.00 $ 400.00 complete and in place Furnish and install 4"X4" MJ tee including all blocking 5 1 EA and restraint as per the plans and specifications, $ 300.00 $ 300.00 complete and in place Furnish and install 4"X2" MJ reducer including all 6 2 EA restraint as per the plans and specifications, $ 300.00 $ 600.00 complete and in place Furnish and install 4" MJ plug including all blocking 7 1 EA and restraint as per the plans and specifications, $ 400.00 $ 400.00 complete and in place Sawcut, remove, and replace asphalt pavement as 8 120 SY per the plans and specifications, complete and in $ 45.00 $ 5,400.00 place Sawcut, remove, and replace 6" curb and gutter as 9 10 LF per the plans and specifications, complete and in $ 15.00 $ 150.00 place Replace one joint of existing 6" AC water line with 6" 10 1 LS C-900 PVC $ 500.00 $ 500.00 CONSTRUCTION TOTAL $ 15,925.00 --'CE OF rF� h1 * : e� •• * 'l SAM J. VERNON �i 99353 l a i I' '•.• ENS,.• ' ,t„syoNAL-?-.S n ORwwsN 1{'' 1 '1\ - Z:\11500\11533- Sterling Heights\ENG\Public Waterline Cost Estimate 4/15/2015 CST se,t,oec .134- 111 r7 e . 4A A ! :. . mer 2 corvN ie+c Add Y1o4-c cv eiv Ccorl vta4ef oorLICohry (Al r cQ.r4- --h/ o or MA.e;r )e Tr-4k, cy oy- o 1 -Nw t4atfar inckaAiii5 neeL � W P.er-1.a4Lirtcli.d4 A -� -1-e1- (gAsed - oY -!a_ - rder t_r lbok.s X1162._ n I ow;n.e.e,r- 'q e weq-ex vices .-SYS ►-, et441fv4441)75)11 >Cinoo-v-rzi ' I sD►rn e._de-ki�Ci C.! $e Gn I1-Lule. A..rit A Cu dt�x=cre -- sae 5ef1Lice._cAn I \a- frbvicuA , k invo1,t 1c, ^ -9 flirt )v\.e $( 3e ry►02' lin-e& C b ClA (teki,Q -I-,.e Puc con 44\s , - t' I int. o - m'e- rl' hted etMey-41re-eS f>k0A,IJ th tdR. of e nAne. 1€-k-( - ov A _ oy\ -�'�•-e_ X12 - r r ►�2 (of ,P1 10o, -tu I gx Yvl is \ 14 wv\ C 'ev-b o✓) 1iU l'e✓V4 I ds +DIoW CJ r . 741, .11.f;4#,;‘/.. 0ilLax f W . Fire I&vlLl 146-4k? 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