Current through Register Vol. XLI, No. 45, November 8, 2024
Section 64-77-8 - Pumping Facilities8.1. General. -- Pumping facilities shall be designed to maintain the sanitary quality of pumped water. Subsurface pits or pump rooms and inaccessible installations shall be avoided. No pumping station shall be subject to flooding.8.2. Location. -- The pumping station shall be located so that the proposed site meets the requirements for sanitary protection of water quality, hydraulics of the system and protection against interruption of service by fire, flood or any other hazard. 8.2.a. Site protection. -- The pumping station shall be: elevated to a minimum of three (3) feet above the one hundred (100) year flood elevation, or three (3) feet above the highest recorded flood elevation, whichever is higher, or protected to such elevations; readily accessible at all times unless permitted to be out of service for the period of inaccessibility; graded around the station so as to drain surface water away from the station; protected to prevent vandalism and entrance by animals or unauthorized persons. The pump station shall be located within a secure area such as a locked building or fenced area; and labeled such that the pumps and valves in the station are tagged to correspond to the maintenance record and for proper identification.8.3. Pumping Stations. 8.3.a. Both raw and finished water pumping stations: shall have adequate space for the installation of additional units, if needed, and for the safe servicing of all equipment; be of durable construction, fire and weather resistant and with outward-opening doors; have a floor elevation of at least six (6) inches above finished grade; have underground structure waterproofed; have all floors drained in such a manner that the quality of the potable water is not endangered; have floors slope to a suitable drain; provide a suitable outlet for drainage from pump glands without discharging onto the floor; provide sampling taps, suction and discharge pressure gauges with stop cocks; and provide metering facilities.8.3.b. Suction well. -- Suction wells shall be watertight, have floors sloped to permit removal of water and entrained solids, be covered or otherwise protected against contamination and have two pumping compartments or other means to allow the suction well to be taken out of service for inspection, maintenance or repair.8.3.c. Equipment servicing. -- Pump stations shall be provided with: crane-ways, hoist beams, eye bolts, or other adequate facilities for servicing or removal of pumps, motors or other heavy equipment; openings in floors, roofs or wherever else needed for removal of heavy or bulky equipment; and a convenient tool board, or other facilities as needed, for proper maintenance of the equipment.8.3.d. Stairways and ladders shall: be provided between all floors and in pits or compartments that are entered; and have handrails on both sides, and treads of non-slip material. Stairs are preferred in areas where there is frequent traffic or where supplies are transported by hand. They shall have risers not exceeding nine (9) inches and treads wide enough for safety.8.3.e. Heating. -- Provisions shall be made for adequate heating for the comfort of the operator and the safe and efficient operation of the equipment. In pump houses not occupied by personnel, only enough heat need be provided to prevent freezing of equipment or treatment process.8.3.f. Ventilation. -- Ventilation shall conform to existing local and state codes. Adequate ventilation shall be provided for all pumping stations. Forced ventilation of at least six (6) changes of air per hour shall be provided for all rooms, compartments, pits and other enclosures below the ground floor and any area where an unsafe atmosphere may develop or where excessive heat may be built up.8.3.g. Dehumidification. -- In areas where excess moisture could cause hazards to safety or damage to equipment, means for dehumidification shall be provided.8.3.h. Lighting. -- Pump stations shall be adequately lighted throughout. All electrical work shall conform to the requirements of the NEC and the relevant state and local codes.8.3.i. Sanitary and other conveniences. -- All pumping stations that are manned for extended periods shall be provided with potable water, lavatory and toilet facilities. Plumbing shall be installed so as to prevent contamination of a public water supply.8.4. Ground Water Pump Stations. -- Where pumping facilities are used, wells and springs shall be vented by properly hooded and screened pipe extending at least twelve (12) inches above the pump station floor or ground surface. Where necessary, provision shall be made for lubricating the pump from a point at least six (6) inches above the top of the well cover, by means that prevents contamination of the water supply. 8.4.a. Driven or Drilled Wells. -- Pumping stations located over driven or drilled wells shall: have riser pipe or casing extending at least six (6) inches, and preferably twelve (12) inches, above the floor, and equipped with a flange or suitable stuffing box; have riser pipe or casing firmly connected to the pump structure or have casing inserted into a recess extending at least one (1) inch into the base of the pump, if a watertight connection is not provided; have the base of the pump not less than six (6) inches above the pump room floor; and have the pump foundation and base designed to prevent water from coming into contact with the joint.8.4.b. Submersible Pumps. -- Where a submersible pump is used, the top of the casing shall be equipped with pitless adaptors or vents, or both, approved by the NSF or WSC with an approved cap to effectively seal against entrance of water under all conditions of vibration or movements of conductors or cables.8.4.c. Discharge Piping. -- Discharge piping shall be provided with means to pump to waste but shall not be directly connected to a sewer. The discharge line shall have control valves located above the pump floor, be protected against freezing, be valved to permit testing and control of each well, have watertight joints, and have all exposed valves protected.8.5. Pumps. 8.5.a. At least two pumping units shall be provided. With any pump out of service, the remaining pump or pumps shall be capable of providing the maximum daily pumping demand of the system. The pumping units shall: have ample capacity to supply the peak demand against the required distribution system pressure without dangerous overloading; be driven by prime movers able to meet the maximum horsepower condition of the pumps; be provided with readily available spare parts and tools; be served by control equipment that has proper heater and overload protection for air temperature encountered; and be able to pump the maximum pumping demand of the system.8.5.b. Suction lift. -- Suction lift shall be avoided, if possible, and be within manufacturers specifications, preferably less than fifteen (15) feet. If suction lift is necessary, provision shall be made for priming the pumps.8.5.c. Priming. -- Priming water shall not be of lesser sanitary quality than that of the water being pumped. Means shall be provided to prevent backpressure or backsiphonage backflow. When an air-operated ejector is used, the screened intake shall draw clean air from a point at least ten (10) feet above the ground or other source of possible contamination unless the air is filtered by an apparatus approved by the BPH. Vacuum priming may be used.8.6. Booster Pumps. 8.6.a. Booster pump stations shall be constructed in accordance with "Pumping Stations," in subsection 8.3 of this section, and shall contain sampling taps and sufficient room for booster chlorination facilities.8.6.b. Booster pumps shall be located or controlled so that they do not produce negative pressure in their suction lines. Pumps installed in the distribution system shall maintain inlet pressure as required in Subdivision 10.2.b under all operating conditions. Pumps taking suction from storage tanks shall be provided adequate net positive suction head. Automatic shutoff or low pressure controller shall maintain at least 20 psi in the suction line under all operating conditions, unless otherwise approved by the BPH. Pumps taking suction from ground storage tanks shall be equipped with automatic shutoffs or low pressure controllers as required by the pump manufacturer. Automatic or remote control devices shall have a range between the start and cutoff pressure that prevents excessive cycling. A bypass shall be available.8.6.c. Duplicate pumps. -- Each booster pumping station shall contain not less than two (2) pumps with capacities such that peak demand can be satisfied with the largest pump out of service.8.6.d. Metering. -- All booster pumping stations shall be fitted with a flow rate indicating and totalizer meter.8.6.e. In-line booster pumps. -- In-line booster pumps shall be accessible for servicing and repairs.8.6.f. Individual home booster pumps. -- Individual home booster pumps shall not be allowed for any individual service from the public water supply main where residual pressures are less than five (5) pounds per square inch under any flow conditions. Where used, backflow prevention, approved by the BPH, consisting of at least a double check valve assembly shall be provided by the customer to protect the public water supply.8.7. Automatic and Remote Controlled Stations. -- All automatic stations shall be provided with automatic signaling apparatus that reports when the station is out of service. All remote controlled stations shall be electrically operated and controlled and shall have signaling apparatus of proven performance. Installation of electrical equipment shall conform with the applicable state and local electrical codes and the National Electrical Code.8.8. Appurtenances. 8.8.a. Valves. -- Each pump shall have an isolation valve on the intake and discharge side of the pump to permit satisfactory operation, maintenance and repair of the equipment. If foot valves are necessary, they shall have a net valve area of at least two and a half (21/2) times the area of the suction pipe, and they shall be screened. Each pump shall have a positive-acting check valve on the discharge side between the pump and the shut-off valve. Surge relief valves or slow acting check valves shall be designed to minimize hydraulic transients.8.8.b. Piping. -- In general, piping shall: be designed so that the friction losses are minimized and not be subject to contamination; have watertight joints; be protected against a surge or water hammer; be such that each pump has an individual suction line or lines are so manifolded that they insure similar hydraulic and operating conditions,8.8.c. Gauges and meters. -- Each pump shall have a pressure gauge on its discharge line, shall have a compound gauge on its suction line, shall have recording meters and gauges in the larger stations (250 gallons per minute or larger) and shall have a means for measuring the discharge. The station shall have indicating, totalizing and recording metering of the total water pumped.8.8.d. Water seals. -- Water seals shall not be supplied with water of a lesser sanitary quality than that of the water being pumped. Where pumps are sealed with potable water and are pumping water of less sanitary quality the seal shall be provided with either an approved reduced pressure backflow assembly or a break tank open to atmospheric pressure and have an air gap of at least six (6) inches or two (2) pipe diameters, whichever is greater, between the feeder line and the spill line of the tank.8.8.e. Controls. -- Pumps, their motors and accessories, shall be controlled in such a manner that they operate at rated capacity without dangerous overload. Where two (2) or more pumps are installed for redundancy, provision shall be made for alternation. Provision shall be made to prevent energizing the motor in the event of a backspin cycle. Electrical controls shall be installed in accordance with NEC requirements. Equipment shall be provided, or other arrangements shall be made, to prevent surge pressures from activating controls that switch on pumps or activate other equipment outside the normal design cycle of operation.8.8.f. Standby power. -- To ensure continuous service when the primary power had been interrupted, a power supply shall be provided from at least two (2) independent sources or a standby or an auxiliary source shall be provided. If standby power is provided by on-site generators or engines, the fuel storage and fuel line shall be designed to protect the water supply from contamination.8.8.g. Water pre-lubrication. -- When automatic pre-lubrication of pump bearings is necessary and an auxiliary direct drive power supply is provided, the pre-lubrication line shall be provided with a valved bypass around the automatic control so that the bearings can, if necessary, be lubricated manually before the pump is started or the pre-lubrication controls shall be wired to the auxiliary power supply.8.8.h. Oil or grease lubrication. -- All lubricants which come into contact with the potable water shall be certified for conformance to ANSI/NSF Standard 60.