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City of Fernley Department of Public Works DESIGN STANDARDS 6.0 - PUMPING FACILITIES 6.1. GENERAL This section covers the requirements and equipment for pumping facilities to be offered for dedication to Public Works. Pumping facilities shall be designed by an engineer with specific related experience. Facilities shall be designed with long term operation and maintenance in mind. Electrical and mechanical designs shall accompany the design for all pumping facilities. Operation and maintenance information shall be provided for all equipment and material and shall consist of the names and addresses of the manufacturer, the nearest representative of the manufacturer, the nearest parts supplier, as well as lubrication information, control diagrams, start-up procedures, operating procedures, preventative maintenance, overhaul instructions, parts list, and a spare parts list. 6.2. WELL PUMPS Well pumps shall be either vertical turbine or submersible pumps. The selection of the type of pump to be used depends on the size of the motor, length of the pump column, and other considerations. In general, a submersible pump shall not be used when the motor size is larger than 100 Hp. Submersible pump facilities shall be equipped with a foot valve and pitless unit. When a submersible pump is used, the well shall be located outside the pumping facility building unless otherwise approved by the City Engineer. Wells equipped with vertical turbine pumps shall be located inside a pump building and shall be equipped with a water lubed shaft and anti- reverse ratchet. Water lubed pumps shall be equipped with suitable automatic pre-lube provisions if necessary as determined by manufacturer’s recommendations. All pumps shall have premium efficiency motors. Pumps shall be constructed in accordance with AWWA C101 Standard for Vertical Turbine Pumps-Line Shaft and Submersible Types. All well pumps shall have a water meter approved by Public Works with a pulse or 4-20ma signal for remote reading capabilities. The pumps shall also have adjustable speed check valves similar to the Clayton 81-02 and deep well pump control valves similar to the Cla-Val Model 61- 02 when required by Public Works. The pump capacity (discharge and total dynamic head) shall be matched as closely as possible with actual operating conditions. All pumps shall have premium efficiency motors unless otherwise authorized by Public Works. The submittal for review shall include pump performance curves, system curves, pump operating ranges and sufficient literature; with detailed specifications. The water system improvement plans shall identify the following operating conditions and performance criteria: • Operating System Functional Description • Casing Diameter • Depth of Well • Screen Location with Respect to Pump Setting • Static Water Level • Pumping Level • Pump Manufacturer and Model • Pump Materials of Construction • Certified Pump Curve from Manufacturer • Pump Intake Setting • Required Pump Discharge PF-1 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS • Total Dynamic Head at Required Discharge • Available Net Positive Suction Head Determination • Maximum Pump Speed (RPM) • Minimum Motor Horsepower • Minimum Efficiency • Motor Protection Features • Motor Soft Starters and/or VFD • Meter Sizing Determination • Air-Vacuum Valve Sizing Determination • Discharge Piping Sizing Determination 6.3. BOOSTER PUMPS Booster pumps shall be vertical line shaft turbines and pump can type. Horizontal-Split Case Pumps will be considered by Public Works on a case-by-case basis. The improvement plans shall state the following operating conditions and performance criteria: • Required Pump Discharge • Certified Pump Curve • System Curves • Pump Operating Range • Total Dynamic Head at Required Discharge • Available Net Positive Suction Head • Maximum Pump Speed • Minimum Motor Horsepower • Minimum Efficiency • Motor Protection Features • Additional booster pump and motor Booster pumps shall be used to move water from a lower pressure zone to a higher-pressure zone. Maximum Day Demands shall be met with 2 pumps operating in parallel and a third pump will be utilized as a back-up. Booster pumps located adjacent to existing water storage facilities are preferred as opposed to drawing suction from distribution lines. The minimum suction pressure allowed will be 30 psi under maximum day demands. A suction supply water tank may be required for proper operation of a booster pumping station. Closed loop pumping is not allowed. Package booster stations are preferred. All pumps shall have premium efficiency motors unless otherwise authorized by Public Works. Fire flow is to be provided from storage and not from booster pumps unless waived by Public Works and/or the Fire District. All design calculations must be stamped by a licensed civil engineer and provided to Public Works for review and approval prior to construction. PRV bypass stations may be considered at booster pumping stations on a case-by-case basis. PRV stations will be below-ground installations and all design calculations must be stamped by a licensed civil engineer and provided to Public Works for review and approval prior to construction. 6.4. SURGE TANKS A registered professional civil engineer must perform a transient surge analysis. A report specifying maximum and minimum pressures and tank size must be provided. A surge tank must PF-2 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS be of the pre-inflated bladder type. The tank shall be constructed of carbon steel and withstand a working pressure of 275 psig. The maximum pressure in the discharge piping shall be damped to 150 psig and minimum pressure at 0 psig. Interior surfaces shall be epoxy coated to 15 mils minimum, NSF approved for potable water systems. Exterior surfaces shall be primed and overcoat 10 mils minimum of Federal Safety Blue epoxy only. The surge tank shall provide an inlet/outlet with an orifice plate to prevent extruding the bladder from the shell. The top of the surge tank shall be removable for access and maintenance and inspections of the bladder. Bladder material shall be constructed of heavy-duty butyl or neoprene. One spare bladder shall be furnished with the tank. The top shall be equipped with a gas charging valve and pressure gauge. All surge tanks shall have operating tank pre-charge specifications on stamped nameplate or in operation manuals. 6.5. MECHANICAL REQUIREMENTS All pumping facilities shall have sufficient surge control to protect piping and other equipment. Pressure fluctuations shall be maintained within 15% of normal operating pressures during pump starting and stopping. Adequate provisions shall be made for pressure surges caused by power outages. Unless approved by Public Works, pressure relief valves or surge anticipator valves will not be permitted for surge protection. In addition, as determined by Public Works, pumps in excess of 25 Hp shall be equipped with "Soft Starters", unless pumps are installed with a Variable Frequency Drive (VFD). Vertical turbine pumps may be required to be equipped with pump control valves as determined by Public Works. The valves shall pump to waste upon start up, then slowly introduce flow into the system and reverse the process when the pump is signaled to stop. All pumps shall be equipped with mechanical seals and magnetic seals. The facilities shall also have a discharge meter and suction and discharge pressure gauges. The discharge meter shall indicate total flow and rate of flow. The discharge meter and pressure gauges (both suction and discharge) shall be suitable for remote reading and shall transmit to the stations control center. The flow meter shall provide an output signal capable of activating the chlorine chemical feed pump. Piping shall be flanged ductile iron or welded steel piping. Adequate pipe stands shall be provided for proper support of piping and equipment. Equipment shall be designed to operate at sound levels not exceeding the best standards established by NEMA or CBM. Provide adequate bases and vibration isolators to prevent transmission of noise. Adequate louvers, heating and ventilation shall also be provided. 6.6. CHLORINATION All well pumping facilities shall be equipped with sodium hypochlorite (HPC) systems utilizing bulk polyethylene containers of HPC solution and solution feed pump with wall mounted shelf. The volume of the hypochlorite storage tank(s) shall be determined by Public Works. The feed pumps must be approved by Public Works. All of the system components shall be according to the manufacturer’s recommendations to insure efficient chlorination system operation. The chlorine chemical feed pump must be electrically connected to the flow meter pulse signal. The chlorination solution drums and pump shall be located in a separate room and be isolated from the rest of the pumping facility. The separating walls shall be sealed masonry block. The design of the room shall comply with the applicable requirements of the most current adopted edition of the International Building Code (IBC) and International Plumbing Code (IPC). Proper warning signage must also be installed outside the separate room. Ventilation must be activated from the outside to provide ventilation prior to entering the room and the vent duct must exhaust outside. A concrete sump sized to handle a minimum of 150 gallons (a larger sump size may be required depending on the number of drums) with a 10 gpm HPC resistant sump pump shall be located in the HPC handling room for chemical spills. The sump pump shall be mounted above PF-3 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS the sump flood elevation and have a 25-foot long, 1” diameter, HPC resistant discharge tube. Chlorination facilities must also include mechanical agitators. Feed line must include check valves and injectors such that the injector can be removed while the main line is under pressure. The bulk drums must be seismically restrained. 6.7. CONTROLS & TELEMETRY Water monitoring and control systems shall consist of a complete radio telemetry system to monitor the status of the pumping facilities. The storage tank level shall control well pumps. The signal to start and stop coming from the telemetry panel. An annual controls contract will be awarded, for the design and installation of all Public Works systems. Public Works has the right to extend the contract indefinitely if needed. The contract is intended to ensure compatibility with existing control and telemetry systems. Control panels shall be equipped with start counters and hour meters for all pumps. Typical functions to be monitored include: 1) Pump Status (if pumps have VFD, pump speed must be monitored) 2) Pump Alarms 3) High Motor Temperature 4) Successive Starts 5) Over-Voltage or Over-Amp draw 6) Water Levels in Wells 7) Suction and Discharge Pressure 8) Moisture in the Pump Room 9) Tank Levels 10) Intrusion alarms 11) Operating Voltage (for each phase leg) 12) Operating Amp Draw (for each phase leg) 13) Water Flow 14) Fire/Smoke Controls and Alarms Well stations shall be equipped with self-generating circular chart recorders, well depth transducers, pressure indicators, and moisture detectors. Moisture detectors shall be located on the floor, in a low point, in both the pump room and the chlorine rooms. 6.8. BUILDINGS & SITE All vertical turbine pumps, booster pumps, mechanical equipment, chlorination facilities, control equipment, electrical equipment and telemetry equipment shall be enclosed in a building. Buildings shall be masonry block (light tan color) with concrete floor and foundation. The building must comply with the applicable requirements of the most current adopted edition of the IBC. The building shall be equipped with chemical resistant fiberglass or Public Works approved coated steel doors with deadbolts keyed to Public Works specifications. The roof shall be brown in color, constructed of wood with 236 lb., Class A Fire Rated, 25-year fiberglass shingles. All wood trim shall be painted dark brown. Where vertical turbine pumps are located within a pump building, adequate provisions shall be made for removal and replacement of the motor, column and pump. These provisions shall include locating the pump within four feet of the wall with a minimum four foot by four foot x roof hatch for removal of the assembly or providing removable roof and/or wall sections. Suitable ventilation shall be required. Where pumps are located within the building, the ventilation equipment shall be suitable to provide five volume changes of room air per hour. PF-4 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS Fans shall be thermostatically controlled and maintain indoor air temperatures below 85 degrees Fahrenheit. Fans and louvers shall be provided with winter covers. The building shall be provided with suitable heaters to keep the interior air temperature above 45 degrees Fahrenheit. Floor drains shall be provided. The building floor shall slope to the drains and fall at a minimum slope of 2 percent. Slotted trench drains are permitted. A zone change to a public facility zone may be required if the parcel is not zoned for public use. The building site shall be landscaped and provided with an irrigation system with automatic controls. The irrigation system shall have backflow prevention and shall have automatic drains to prevent freezing. All well pumping facilities shall be fenced with six- foot high fabric with 2-inch mesh, 9- gauge zinc coated wire, wood or fiberglass slatted, and topped with three strands of barbed wire. Access shall be through a sixteen (16) foot wide double gate. The site access, size and layout shall provide adequate room for maintenance of the facility, including removal and reinstallation of well pumps. Ample room is required for pump pulling equipment and a stem trailer. The site shall provide for proper access and allow for adequate site drainage. Permits that are required for the construction of a pumping facility building shall be put in the name of the City of Fernley. 6.9. STAND-BY GENERATOR All pumping facilities shall be provided with a stand-by engine generator and shall be provided with automatic starting and load transfer equipment (automatic transfer switch) to operate the entire pumping load during power failure unless the pumps have a v-drive backup motor with an alternative fuel source. The generator shall have a seamless transfer of power during shutdown, when commercial power is re-applied to pump motor. The generator shall be located in a weather-protective, sound-proofed, lockable housing with access to all engine and generator components for servicing and maintenance. The generator shall be fueled by diesel with an above-ground storage tank and concrete pad for secondary containment, or by natural gas as approved by Public Works. The storage tank shall have a capacity to provide 24-hour continuous run time. The generator and engine block shall be equipped with a block heater and thermostat that will allow for instantaneous start-up at -10 degrees Fahrenheit. The engine shall be protected with shutdown safeguards, gauges and indicator lamps for over-temperature, low oil pressure, over-speed and over-crank. The engine shall be equipped with an automatic battery trickle- charger, installed on the hot side of the transfer switch enabling the battery to maintain a charge when idle. The machine will include vibration isolators. All power generation units shall be sized and designed by an electrical engineer licensed in the State of Nevada. 6.10 START-UP AND OPERATION Prior to approval or acceptance by Public Works, the developer or owner shall commission all systems including pumps, controls, and equipment to verify performance, function, and correct operation by performing procedures to activate, startup, adjust, test, and demonstrate the system in operating order in accordance with the approved plans and specifications. To insure that the work is ready for full-time operation, the developer shall include procedures for the verification, balancing, calibration, witness testing, documentation, and inspection by equipment manufacturers. Training of Public Works operators shall also be provided. The developer shall include the following items in the start-up activities, and other items that are necessary to operate and maintain the system: PF-5 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS 1. Perform initial lubrication of equipment and have manufacturers check and adjust equipment. Provide maintenance, lubrication and personnel as required for test operation until Public Works accepts the project. 2. Perform testing of electrical work prior to energizing electrical systems. 3. Calibrate all instruments. 4. Test-operate all equipment. 5. Public Works shall be notified in writing 10 days before complete facility operation is to occur. Under the supervision of Public Works, the developer shall start-up and operate the facility on a complete full time basis beginning on the acceptance date. At no time during this initial operation shall the developer operate any Public infrastructure without Public Works approval. The developer shall provide the Engineer-of-Record, a mechanic, electrician, instrument engineer, representatives of manufacturers of equipment, and other personnel to adjust, repair, and correct deficiencies as required to keep the facilities in continuous operation for a period of 10 days. The developer shall also furnish all mechanical and electrical personnel as required to make adjustments to and perform all required maintenance for the operating equipment until the end of the 10-day initial operation period. Maintenance of equipment shall include lubrication, adjustments, replacements, and modifications as required. 6. Following completion and approval of the 10-day initial operation period, Public Works will take over operation and maintenance duties. If continuous operation is interrupted for a period of four consecutive hours or more due to a failure of equipment or work, the 10-day initial operation period shall be restarted at day one. At the end of one year from the date of acceptance, another test will be performed by Public Works to verify efficiency and operating condition of all pertinent facilities. Any deficiencies as evidenced by the test will be corrected by the developer under warranty. 7. Submit documentation of test reports and calibration results to Public Works during the 10- day initial start-up period within 10 days of completion. 8. Prior to the 10-day initial start-up period, the developer shall submit to Public Works affidavits from the manufacturers stating that the equipment has been properly installed, tested, and adjusted. The affidavit shall contain the following wording: “The (Name of Equipment) has been properly installed, tested, adjusted, lubricated, and calibrated, and is ready for full time operation. The installation has been inspected and been found to be in accordance with our (the manufacturer’s) standards and requirements.” 9. The developer shall provide training to Public Works operators which shall include a demonstration of the operation, maintenance, and safety procedures for all facilities. Training of Public Works operators shall be performed separate from facility start-up and commissioning. In the event that the facility does not meet the approved plans and specifications, the owner/developer will come up with a design to meet the original approved plans and specifications. Public Works will not submit a design by review. The costs of any additional designs, equipment and implementation will be paid by the developer. 6.11 OPERATIONS AND MAINTENANCE MANUAL Four copies of an operations and maintenance manual shall be submitted to Public Works upon completion of construction and prior to acceptance of facilities or improvements, pump stations, and distribution mains. The operations and maintenance manual shall contain the following as a minimum: 1) Listing of emergency telephone numbers for Public Works PF-6 May 2008 ---PAGE BREAK--- City of Fernley Department of Public Works DESIGN STANDARDS 2) Priority calling list 3) List of abbreviations 4) General narrative of the facility a) Introduction b) Objectives of the facility c) Facility design criteria 5) Operating instructions a) Facility description b) Emergency operation (discussion of potential facility failures and procedures for responding to emergency operations) 6) Operating records 7) Monitoring and treatment processes 8) Stand-by power operations 9) Maintenance instructions a) General instructions b) Maintenance records c) Maintenance of motors and drives d) Maintenance of pumps e) Maintenance of treatment/process equipment f) Maintenance of valves g) Maintenance of instrumentation and meters h) Maintenance of stand-by power i) Maintenance of pressure reducing stations (if applicable) 10) Facility safety a) General b) Confined spaces c) Electrical safety d) Explosion hazards e) Process facilities f) Pump rooms g) Collecting samples h) Equipment set-up and performance tests i) General safety considerations 11) Appendices and required a) Permits b) Figures and drawings PF-7 May 2008