30 Tex. Admin. Code § 217.61

Current through Reg. 49, No. 45; November 8, 2024
Section 217.61 - Lift Station Pumps
(a) General Requirements. A raw wastewater pump, with the exception of a grinder pump, must:
(1) be designed to prevent clogging;
(2) be capable of passing a sphere of 2.5 inches in diameter or greater; and
(3) have greater than 3.0 inch diameter suction and discharge openings.
(b) Submersible and Non-submersible Pumps.
(1) A non-submersible pump must have inspection and cleanout plates on both the suction and discharge sides of each pumping unit that facilitate locating and removing blockage-causing materials, unless the pump design accommodates easy removal of the rotation elements.
(2) A pump support for a submersible or non-submersible pump must prevent movement and vibration during operation.
(3) A submersible pump must use a rail-type pump support system with manufacturer-approved mechanisms designed to allow personnel to readily remove and replace any single pump without entering or dewatering the wet well.
(4) Submersible pump rails and lifting chains must be constructed of a material that performs to at least the standard of Series 300 stainless steel.
(5) All lift station pumps and associated appurtenances must be designed to prevent the discharge of wastewater from the lift station and at all points in the upstream collection system.
(c) Lift Station Pumping Capacity. A lift station must have at least two pumps. The firm pumping capacity of a lift station must handle the peak flow.
(d) Pump Head Calculations.
(1) An owner must select a pump based upon analysis of the system head and pump capacity curves. The owner must determine the pumping capacities and pressure head requirements of a single pump operating alone, and with other pumps.
(2) The engineering report must include pipe head loss calculations, using the American National Standards Institute's Hydraulic Institute Standards pertaining to head losses through pipes, valves, and fittings.
(3) The engineering report must include the friction coefficient (Hazen-Williams "C" value) used in friction head loss calculations. The selected friction coefficient must be based on the pipe material.
(4) For a lift station with more than two pumps, a force main in excess of one-half mile, or a lift station with a firm pumping capacity of 100 gallons per minute or greater, the engineering report must include system curves for both the normal and peak operating conditions at friction coefficient values (C values) for the force main pipe.
(e) Flow Control.
(1) A lift station or a transfer pumping station located at or discharging directly to a wastewater treatment facility must have a peak pump capacity equal to or less than the peak flow, unless equalization is provided.
(2) Each lift station or transfer pumping station located at or discharging directly to a wastewater treatment facility with a peak flow that is greater than 300,000 gallons per day must use three or more pumps, unless duplex, automatically controlled, variable capacity pumps are used.
(3) Each lift station or transfer pumping station located at or discharging directly to a wastewater treatment facility with a peak flow that is less than or equal to 300,000 gallons per day must use at least two pumps.
(f) Self-Priming Pumps.
(1) A self-priming pump must be capable of priming without relying on a separate priming system, an internal flap valve, or any other external method for priming.
(2) A self-priming pump must use a suction pipe that produces flow with velocity of at least 3.0 feet per second but not more than 7.0 feet per second. A self-priming pump must have its own suction pipe.
(3) A self-priming pump must vent air back into the wet well during priming.
(g) Vacuum-Priming Pumps.
(1) A vacuum-primed pump must be capable of priming by using a separate positive priming system with a dedicated vacuum pump for each main wastewater pump.
(2) A vacuum-priming pump must produce a suction pipe velocity between 3.0 and 7.0 feet per second. A vacuum priming pump must have its own suction pipe.
(h) Vertical Positioning of Pumps. A raw wastewater pump must maintain positive static suction head during normal on-off cycling. A submersible pump with "no suction" pipes, a vacuum-primed pump, or a self-priming unit capable of satisfactory operation under any negative suction head anticipated for the lift station is not required to have positive static suction head during normal on-off cycling.
(i) Individual Grinder Pumps. A grinder pump is not subject to the requirements of this subchapter if:
(1) the grinder pump is not part of an alternative collection system as defined by this chapter; and
(2) the grinder pump only serves a single connection to a wastewater collection system.
(j) Pump for Low-Flow Lift Station. A pump used for a lift station with a peak flow of less than 120 gallons per minute must be submersible and include a grinder.

30 Tex. Admin. Code § 217.61

The provisions of this §217.61 adopted to be effective August 28, 2008, 33 TexReg 6843; Amended by Texas Register, Volume 40, Number 47, November 20, 2015, TexReg 8307, eff. 12/4/2015