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Project Report 001FORRESTER HEIGHTS Yelm, Washington WATER BOOSTER PUMP STATION PROJECT REPORT Prepared for. FH1, LLC 4200 6~" AVE SE Suite 301 Lacey, WA 96503 16 October 2007 Prepared by: Benjamin E. Enfield Nicholas D. Taylor Reviewed by Project No.: 406050.10 WVi~ Cons ul fi n9 En 9ineers 4200 Sixth Avenue, Suite 309 Lacey, VJA 98503 Forrester Heights Booster Pump Station Project Report TABLE OF CONTENTS Page Overview and Planning 1. Sizing Analysis 1 2. Hydraulic Analysis I Equipment Specifications 3 3. BuildinglPump-house Details 7 4. Reliability 8 6. Ownership 9 7. Maintenance 9 APPENDICES Appendix A System Plans Including Project Layout Map, Building/Pump-house Details, Structural Details, and Site Piping Plan Appendix B Equipment Specifications Appendix C Booster Pump System Controls Electrical Schematic Appendix D General Routine Operation and Preventative Maintenance Schedule KPFF Consulting Engineers i 18 October 2007 Project No.: 406050.10 Forrester Heights Booster Pump Station Project Report Overview and Planning This report has been submitted for the construction of a permanent closed system Booster Pump Station (BPS) near the intersection of Forrester Heights Drive and Highway 507 in Yelm, Washington, to meet required pressure demands for the proposed Forrester Heights Development Phase 1, which consists of 24 single-family residential lots. The proposed BPS includes three (3) skid-mounted booster pumps and their associated piping, a control system, a bladder tank, a backup power generator, and a sheltering structure as specified in the construction documents included in Appendix A. Manufacturers' material details, electrical schematics, and structural calculations will be submitted as part of the construction submittal package. Pressure testing of the newly constructed 10-inch water main serving the Forrester Heights Development indicates that adequate residual pressure is not available at the high point of the system, which is approximately 60-feet higher than the proposed BPS. Analysis of alternative solutions by the project engineer and the City of Yelm determined that the construction of a BPS is the most economical means to provide adequate residual pressure for the proposed residential lots. The proposed BPS will splice into the newly constructed 10-inch water main and is designed to provide adequate residual pressure to the high point of the system for the required fire flow and peak daily demand of the proposed Forrester Heights Development. The proposed BPS shall be constructed upon project approval by the necessary agencies. This report will demonstrate that the proposed BPS will provide adequate system capacity and reliability for the proposed Forrester Heights Development. The City of Yelm is aware of the proposed BPS and its necessity as well as the estimated capital and operating costs associated with the water system Improvement. This report has been prepared in accordance with Washington State Department of Health (WSDOH) Water System Design Manual dated August 2001. KPFF Consulting Engineers 1 19 October 2007 Project No.: 406050.10 Forrester Heights Boaster Pump Station Project Report 1. Sizing Analysis Determination of Pumoinc Svstem Discharoe Capacity Requirements: The BPS must be able to provide minimum capacity for both normal operating conditions and fire flow demand of the development. Normal Ooeratino Conditions: The BPS must be able to provide the peak hourly demand (PHD) to the service area and maintain a minimum of 30 psi at all service connections. Peak hourly demand is calculated using the Washington State Department of Health: Water System Design Manual, as follows: Service area=24 single family residences PHD = (MDD/1440)[(C)(N) +F] +18 Where: PHD = Peak Hourly Demand (gpm) C = Coefficient Associated With Ranges of ERU's N = Number of Service Connections, ERU's F = Factor Associated with Ranges of ERU's MDD = Maximum Day Demand, (gpd/ERU) =ADD x 2 ADD = Average Day Demand (gpd/ERU) =(8000/ARR)+200 ARR = Average Annual Rainfall, (in/yr) Knowing that 24 residential service connections(ERU's) are proposed and using table 5-1 of the Water System Manual; N= 24, C=3.0, and F=O. The closest rainfall monitoring station maintained by the Western Regional Climate Center(WRCC) is in Olympia, WA. The WRCC online database shows that the average annual rainfall is 50.68 in/yr. (ARR=50.88 in/yr) Therefore: ADD = (8000/50.88) +200 = 357.2 gpd/ERU' MDD = 357.2 z 2 = 714.4 gpd/ERU' PHD = (714.4/1440)[(3.0 z 24) + 0] + 18 = 53.7 gpm The peak hourly demand of the system is 53.7 gpm with a minimum pressure of 30 psi at all service connections. 'The City of Yelm has documented an ADD of 300 gpd. Fire Flow Condition: The BPS must be able tc provide a fire flow of 750 gpm, as dictated by the City of Yelm, plus the calculated peak hourly demand to the service area and maintain a minimum of 20 psi at all points in the distribution system. Fire Flow Demand = 750 gpm + 53.7 gpm = 803.7 gpm The fire flow demand of the system is 803.7 gpm with a minimum pressure of 20 psi at all points of the distribution system. KPFF Consulting Engineers 2 16 October 2007 Project No.: 406050.10 Forrester Heights Booster Pumc Station Total Dvnamic Head Required: The total dynamic head (TDH) that the booster pump must work against is shown as follows: TDH = He+ ~' Hr+ H~- Hs Where: HQ = Static Discharge Head (ft) s'. Hr = Sum of Minor Losses (ft) [pipe friction, fittings, etc] H~ = Discharge Head (ft) Hs = Suctign Head (ft) He= 65ft (elevation difference between high point of system and pump) Minor losses include friction losses (His), fittings losses and losses through the pumps. Friction losses were computed using the Hazen-Williams equation. Fora 10" PVC pipe at 804 gpm the friction loss is 0.316 ft/100-ft of pipe. Added to this is a conservative estimate of 10.0 ft for fittings losses and 15.0 ft of losses through the BPS itself. ~'Hr= (1580ft/100)x0.316+30ft For peak hourly demand and fire flow demand a minimum pressure of 30 psi and 20 psi is required respectively. A pressure of 30 psi correlates to H~ of 69.3 ft and 20 psi correlates to a H°of 46.2 ft. The existing pressure of 44 psi at the connection correlates to a Hsof 101.6 ft. Therefore: Peak Hourly Demand TDH @ 30 psi, 53.7 gpm = 65ft + 30ft + 69.3ft - 101.6ft = 62.7ft Fire Flow Demand TDH @ 20 psi, 803.7 gpm = 65ft + 30ft + 46.2ft - 101.6ft = 39.6ft The system demand information was used to select the pumps and equipment for this project. 2. Hydraulic Analysis/Equipment Specifications Pumps The specified pumps are three (3) Grundfos CR 64-1-1 vertical, non-self priming, multistage, in-line, centrifugal, variable speed pumps. Figure 1 below indicates that one (1) Grundfos CR 64-1-1 pump will be capable of supplying the required residual PHD pressure of 30 psi (62.7 ft TDF) at 339 gpm; much more than the required 53.7 gpm. Single pump effciency will be 70.8%. KPFF Consulting Engineers 3 18 October 2007 Project Na.: 406050.10 Forrester Heighfs Booster Pump Station Project Report Figure 1 37253000 CR 647-1 H GA gat-t ~fll D=33B US GPU H=82]C t]0 T_=].B HP ~ ``~ ~` PA ~~. ~` ~ ` 74 53 ._ \. ..... .. /~ ` ` A l\ ' ~ t q0 ~ ~. ap i. 1~. Z] 1e 00 SA tOC 15e 200 250 300 350 400 ptl:5 GPR11 P2 (HP) tV B e p 2 0 KPFF Consulting Engineers 4 180ctober 2007 Project No.: 406050.10 Forrester Heights Booster Pump Station Project Report Figure 2 37257000 CR 547-0 H z cn Sal-i fftY C= eA ^5 @PM H=36.5 P. P2=1.dHP ~~ _ W ~ ` ~` ~ Pl \ ~ A A ~ ~\ i 7 ~.\ ~ ea `.~ ` ~ ~ \ A '., \ . ~ 43 . \ _. ,~ 3a \. ~. ?~ in d G WO 20G 360 600 5C0 8G3 iCO SOG ~y1G GPMI P2 ~HP7 18 L' 3 ~~ _. KPFF Consulting Engineers 5 18 October 2007 Project No.: 406050.10 Forresfer Heights Booster Pump S[ation Project Report 2. Hydraulic Analysis /Equipment Specifications (Continued) Figure 2 above indicates that two (2) Grundfos CR 64-1-1 pumps in parallel will be capable of supplying the required residual fire flow demand pressure of 20 psi (39.6 ft TDH) at 821 gpm; more than the required 803.7 gpm. Dual pump efficiency will be 52.9% and is acceptable as very infrequent use of a second pump is foreseen. The third pump shall only operate in a backup capacity and will be utilized during maintenance or emergency periods when another pump is off-line. The specified pumps are variable speed and shall be operated by the control system as specified below. Technical specifications for the proposed pumps are provided in Appendix 8. Pump startup and performance testing routines shall be performed as prescribed by the pump manufacturer's data. Pioin All interior piping and fittings within the pump house shall be ductile iron, AWWA C205 steel, galvanized iron pipe, or copper piping. PVC piping shall not be used. All piping to and from the BPS is in place and connection of the BPS shall entail ftting the intake and outlet pipes of the BPS to the existing 10"x6" reducers. Due to the supplemental nature of the proposed BPS, a pipe by-pass around the pumping equipment is already in place. All piping shall be secured using strapping, thrust blocking, and/or necessary restraint as prescribed by AWWA specifications. Valvino All system valves shall be resilient wedge, non-rising stem, with o-ring seals. Valve ends shall be mechanical joint or ANSI flanges. Valves shall conform to AWWA C509-80. Valves shall be Mueller, M & H, Clow, Kennedy, or equal. Controls All three (3) BPS pumps shall be connected by wire to the BPS control system. The control system shall consist of a surge arrestor, voltage control monitor, ammeters, enclosure lighting control, system alarm control, thermostat, emergency operation controls, control panel signal unit, primary and suction pressure sensors, water shortage switch, external fault, remote setpoinVredundant sensor, overpressure protection, system fault, facility data communication link, surge suppression capability, and the like. The BPS control system electrical wiring schematic featured in Appendix C is the Grundfos Model F, 3-pump control system. Final control system wiring schematic and/or any variation from the specified control system shall be approved by the design engineer prior to construction. The proposed electrical system shall meet all applicable federal, state, and local codes. KPFF Consulting Engineers 6 18 October 2007 Project No.: 406050.10 Forrester Heights Booster Pump Station Project Report The control system shall be equipped with a generator activation feature to start the emergency power generator, which is specified in section 4 of this report, during loss or surge of power. The control system alarm shall feature an external visual and auditory alarm that is signaled by a pump failure, overheating, loss of necessary net-positive suction head, dry running, and any other less than ideal operating states. An alarm battery back-up shall be provided to operate the alarm system during power outages. Bladder Tank/Surge Protection Although the specified pumps are equipped with variable speed motors, constant running and frequent starts lead to faster pump degradation, more frequent maintenance, and earlier replacement. The proposed BPS system shall include a 132 gallon, American Society of Engineers (ASME) certified bladder tank. The tank size is specified by the Grundfos pump manufacturer to adequately protect boaster pumps. A bidder proposed bladder submittal shall be approved prior to construction of the proposed BPS. The bladder tank will also act as surge and water-hammer protection for the BPS. General All materials, installation, and workmanship shall conform to the Standard Specifications for Road, Bridge, and Municipal Construction published by the Washington State Department of Transportation (WSDOT) and the American Water Works Association (AWWA) standard specifications latest editions thereof. Performance and sizing standards shall conform to AWWA, American Public Works Association (APWA), WSDOT, and WSDOH guidelines. All components in contact with water shall be NSF approved. 48 hours notice shall be given to customers for a planned interruption of service. Every effort shall be made to keep the service interruption to a minimum. Excavations and shoring shall conform to Labor and Industries (LI) standards for worker safety. 3. Building/Pump-house Details The pump-house shall be bidder designed, however certain pump-house features, as outlined below, are required. The final pump-house design shall be approved by the design engineer prior to construction based on contractor provided submittals. A conceptual pump-house layout is included in Appendix C. Mounting Surface The proposed pump-house shall be mounted to a flat reinforced broom-finished concrete pad and shall be affixed to the pad by embedded threaded anchors. Concrete pad, reinforcement, and mix design shall be constructed as specified in the construction documents included in Appendix A. KPFF Consulting Engineers 7 18 October 2007 Project No.: 406050.10 Forrester Heights Booster Pump Station Project Report Electrical Panel The electrical panel shall be wall or post mounted and shall be a 200 amp 120/208V/B- phase panel with auto-transfer switch. The panel shall also include one (1) 120 volt, 20 amp, GFI outlets Temperature Control Pump-house temperature shall be monitored by the BPS control system. Internal high ambient temperature thermal protection is provided by the specified pumps. Low temperature thermal protection shall be provided by a single 1500 watt forced air electric heater that is wall mounted and Includes a remote thermostat. One 50 cfm exhaust fan shall be installed with a remote timer and shall be ducted to the exterior to control humidity and prevent overheating in the summer. Pump-house insulation shall be provided as required by the pump-house equipment manufacturer's specification. Liohtin Besides exterior alarm system lighting, one exterior 200 watt flood light shall be provided. Two interior 100 watt lights shall be provided with a switch near the pump-house door. Security The BPS doors shall be kept locked at all times. A City of Yelm official or appointed facility management agency shall maintain responsibility for access to the proposed BPS. The exterior generator area shalt be surrounded by a 6 foot high chain-link security fence with a locking gate. Access to the fenced area shall also be controlled by a City of Yelm official or appointed facility management agency. Miscellaneous A sample tap shall be installed within the pump-house and shall be connected to the BPS outflow pipe. A pressure relief valve shall be installed on the outlet side of the BPS. Pump-house and pump-house access shall be constructed in a manner that will allow access to the BPS by any necessary equipment. 4. Reliability The BPS is designed to provide adequate service during periods when one pump is not in operation. This designed redundancy will ensure that peak hourly and fire flow demand at the required residual pressure are available to the service connections at all times. A configuration of three identical pumps in parallel is specified with the third pump strictly for redundancy in the case that one pump fails. The system will be setup with one variable frequency drive (VFD) in the control panel to provide more efficient operation for average KPFF Consulting Engineers 8 18 October 2007 Project No.: 406050.10 Forrester Heighfs Booster PUmo Station system demands. When the demand increases beyond the capacity of the first pump then the other pumps will activate one by one as needed. One pump will be able to supply domestic demand and two pumps will be able to supply fire flow demand. The third pump is provided for redundancy In case of a pump failure or maintenance outage. The BPS will also include a 35 KW diesel generator, as specified in Appendix B, to supply power to the pumps in the event of a power outage. Any power outage or interruption of normal BPS operation shall be signifed by an exterior visual and auditory alarm. 5. Ownership After construction and acceptance, the water system infrastructure will be owned and maintained by the City of Yelm as part of the City water system. 6. Maintenance Table A, General Routine Operation and Preventative Maintenance Schedule, which is included in Appendix D, outlines suggested daily, monthly, quarterly and annual maintenance activities for the system. It is the responsibility of the system owner to ensure that maintenance of the water system as described in the table is carried out. Records of maintenance performed, as well as any repairs made to the system, shall be kept on file with the water system. Operational data shall be recorded monthly. A log shalt be maintained recording system pressure, service logs, run-time meter readings, etc.... Provided herein are more specific guidelines for operation and maintenance of equipment for this water system: Booster Pumps This centrifugal pump requires little or no service other than reasonable care and periodic cleaning. Occasionally, however, a shaft seal may become damaged and must be replaced. The procedure as outlined by the manufacture will enable replacement of the seal. Most pump problems are caused by electrical problems. Minor control boz components or outside electrical difficulties (such as low voltage) can cause a malfunction. Before removing the pump from service, check motor windings for damage (check winding resistance with an ohmmeter per owners manual). Centrifugal pumps need to be manually operated on a monthly basis to ensure that they are functioning properly. Also, on a monthly basis the hourly run-time meters for each pump must be read and recorded. Bladder Tanks Bladder tanks are relatively maintenance free. The air pressure in each tank should be checked monthly and the air replenished as needed. Each bladder tank should be drained and recharged with air annually to ensure that it is functioning properly. With age, the bladder inside the tank may develop small cracks. This allows water inside the tank between the bladder and the tank wall. This is not a sterilized area and may be a KPFF Consulting Engineers 9 18 Project No.: 406050.10 Forrester Heights Booster Pump Station Project ftepoR source of bacterial contamination. If a tank does become waterlogged due to a failure of the bladder membrane, the tank must be replaced. Until the tank can be replaced, it should be taken out of service to prevent any possible contamination of the water system. Svstem Valves All the valves in the water system shall be operated quarterly through their full operating range. Exercise valves once a year to ensure that they will be operable when needed for maintenance or emergency repairs. Replace or repair valves that do not operate properly. Electrical Svstem A complete Inspection of the electrical system shall be performed annually. Loose connections shall be tightened. Pump relays, switches, and all other controls shall be checked to ensure they are in operating order. Be sure to check the ground system ground as well. Backup Generator An automatic transfer switch starts the generator when there is a power failure. The generator will also start up once a week and run for approximately 15 minutes. This will ensure the system is working when the power goes out. Check weekly to make sure the system is operating properly, especially during winter months. The fuel for this generator is diesel. The fuel level must be checked monthly at a minimum. Replenish fuel as required. Fluid levels in the generator engine must be checked and replenished as required. Follow the manufacturers recommendations. Make necessary repairs in a timely manner so that the generator is functional when needed. Disinfection If a distribution main breaks or other components of the water system that are in contact with the water are exposed to the atmosphere or other potential contamination source, the equipment shall be disinfected prior to being put back into service per the appropriate AWWA specification for disinfection. The following is a list of the AWWA specifications. AWWA C651, Disinfecting Water Mains AWWA C652, Disinfection of Water Storage Facilities AWWA C653, Disinfection of Water Treatment Plants AWWA C654, Disinfection of Wells KPFF Consulting Engineers 10 18 October2007 Project No.: 406050.10 Appendix A Sysfem Plans Including Project Layout Map, Building/Pump-house Details, Structural Details, and Site Piping Plan