Mo. Code Regs. tit. 10 § 20-8.130

Current through Register Vol. 49, No.12, June 17, 2024

Section 10 CSR 20-8.130 - Pumping Stations

PURPOSE: This amendment will retain and add minimum design standards for pumping stations that are required to protect or improve public health, safety, and water quality.

PURPOSE: This rule specifies the minimum standards for the design of pumping stations that are part of wastewater collection and treatment systems. This rule is to be used with rules 10 CSR 20-8.110 through 10 CSR 20-8.210. It does not address all aspects of design, and the design engineer may refer to other appropriate reference materials so long as these minimum standards set forth in this rule are met.

(1) Applicability. Wastewater systems that utilize pumping stations shall be designed based on criteria contained in this rule, published standards, applicable federal and state requirements, standard text- books, current technical literature, and applicable safety standards. In the event of any conflict between the above criteria, the requirement in this rule shall prevail.

(A) This rule shall not apply to treatment units covered in 10 CSR 20-8.300.

(B) This rule shall not apply to treatment units covered in 10 CSR 20-8.500.

(2) General.

(A) Flood Protection. For flood protection follow the provisions in 10 CSR 20-8.140(2)(B).

(B) Access Road. For access roads to pump station sites follow the provisions in 10 CSR 20-8.140(2)(D).

(C) Safety. For safety follow the applicable portions of 10 CSR 20-8.140(8).

(D) Potable Water Sources. The distance between wastewater pumping stations and all potable water sources shall be at least fifty feet (50') in accordance with 10 CSR 23-3.010(1)(B).

(E) Housed Wet Wells. Housed wet well ventilation shall be in accordance with 10 CSR 20-8.140(8)(J).

(3) Design.

(A) Structures.

1. Separation. Dry wells, including their superstructure, shall be completely separated from the wet well with gas tight common walls.

2. Access. Suitable and safe means of access to dry wells and to wet wells shall be provided to persons wearing self-contained breathing apparatus.

(B) Pumps.

1. Multiple units. Multiple pumps shall be provided except for design average flows of less than fifteen hundred (1,500) gallons per day.

2. Electrical equipment. Electrical equipment shall be provided with the following requirements:

A. Electrical equipment must comply with 10 CSR 20-8.140(7)(B);

B. Utilize corrosive resistant equipment located in the wet well;

C. Provide a watertight seal and separate strain relief for all flexible cable;

D. Install a fused disconnect switch located above ground for the main power feed for all pumping stations.

E. When such equipment is exposed to weather, it shall comply with the requirements of weather proof equipment; enclosure NEMA 4; NEMA 4X, where necessary; and NEMA Standard 250- 2014, published December 15, 2014. This standard shall hereby be incorporated by reference into this rule, as published by National Electrical Manufacturers Association, 1300 North 17th Street, Arlington, VA 22209. This rule does not incorporate any subsequent amendments or additions;

F. Install lightning and surge protection systems;

G. Install a one hundred ten volt (110 V) power receptacle inside the control panel located outdoors to facilitate maintenance; and

H. Provide Ground Fault Circuit Interruption (GFCI) protection for all outdoor receptacles.

(C) Controls. Water level controls must be accessible without entering the wet well.

(D) Valves. Valves shall not be located in the wet well unless integral to a pump or its housing.

(E) Wet Wells. Covered wet wells shall have provisions for air displacement to the atmosphere, such as an inverted and screened "j" tube or other means.

(F) Ventilation. Interconnection between the wet well and dry well ventilation systems is not acceptable. For ventilation follow the provisions in 10 CSR 20-8.140(8)(J).

(G) Water Supply. There shall be no physical connection between any potable water supply and a wastewater pumping station, which under any conditions, might cause contamination of the potable water supply. If a potable water supply is brought to the station, comply with conditions stipulated under 10 CSR 20-8.140(7)(D).

(4) Suction Lift Pumps.

(A) Self-Priming Pumps. The combined total of dynamic suction lift at the "pump off" elevation and required net positive suction head at design operating conditions shall not exceed twenty-two feet (22').

(B) Vacuum Priming Pumps. Vacuum priming pump stations shall be equipped with dual vacuum pumps capable of automatically and completely removing air from the suction lift pump.

(C) Wet Well Access. Wet well access shall not be through the equipment compartment. Access shall be provided in accordance with paragraph (3)(A)2. of this rule.

(5) Submersible Pump Stations. Submersible pump stations shall meet the applicable requirements under section (3) of this rule, except as modified in this section.

(A) Pump Removal. Submersible pumps shall be readily removable and replaceable without personnel entering, dewatering, or disconnecting any piping in the wet well.

(B) Valve Chamber and Valves. Valves required under subsection (3)(D) of this rule shall be located in a separate valve chamber.

1. Access. A minimum access hatch dimensions of twenty-four inches by thirty-six inches (24" x 36") shall be provided. For access, follow the provisions in paragraph (3)(A)2. of this rule.

2. Portable pump connection. A portable pump connection on the discharge line with rapid connection capabilities shall be provided.

(6) Alarm Systems. Alarm systems with an uninterrupted power source shall be provided for pumping stations.

(7) Emergency Operation.

(A) In addition to the required emergency means of operation and a storage/detention basin or tank, the following minimum retention time shall be provided:

1. For facilities with a design average flow of one hundred thou- sand (100,000) gallons per day or greater, a storage capacity for two- (2-) hour retention of the peak hourly flow; or

2. For facilities with a design average flow of less than one hundred thousand (100,000) gallons per day, a storage capacity for four- (4-) hour retention of the peak hourly flow.

(B) Independent Utility Substations. Where independent substations are used for emergency power, each separate substation and its associated distribution lines shall be capable of starting and operating the pump station at its rated capacity.

(C) Protection of Water Supplies. For separation between water mains and sanitary sewer force mains follow the provisions in 10 CSR 20-8.120(5).

(D) Locator wire. For locator wire follow the provisions in 10 CSR 20-8.125(5)(A) 5.

(8) Force Mains.

(A) Design. Force main system shall be designed to withstand all pressures (including water hammer and associated cyclic reversal of stresses), and maintain a velocity of at least two feet (2') per second.

(B) Installation. For installation follow the provisions in 10 CSR 20-8.120(3)(A).

(C) Protection of Water Supplies. For separation between water mains and sanitary sewer force mains follow the provisions in 10 CSR 20-8.120(5).

(D) Locator wire. For locator wire follow the provisions in 10 CSR 20-8.125(5)(A) 5.

10 CSR 20-8.130

AUTHORITY: section 644.026, RSMo Supp. 1988.* Original rule filed Aug. 10, 1978, effective 3/11/1979.

Amended by Missouri Register January 2, 2019/Volume 44, Number 1, effective 2/28/2019

The secretary of state has determined that the publication of this rule in its entirety would be unduly cumbersome or expensive. The entire text of the material referenced has been filed with the secretary of state. This material may be found at the Office of the Secretary of State or at the headquarters of the agency and is available to any interested person at a cost established by state law.

*Original authority 1972, amended 1973, 1987, 1993.