Section 410IAC6-10.1-67. Sewage lift stations and force mains

   (a) Sewage lift stations:

(1) must be protected from damage by a one hundred (100) year flood event; and

(2) shall remain fully operational and accessible by maintenance vehicles during a twenty-five (25) year flood event and all weather conditions.

  (b) Submersible pumps and motors must be designed specifically for raw sewage use. Pumps must be readily removable for maintenance, repair, or replacement by installation with guide rail systems, breakaway flanges, and lifting chains.

  (c) Except where grinder or cutter pumps are used, raw sewage pumps shall be capable of passing spheres of at least three (3) inches in diameter. Effluent pumps may be used in lift stations following septic tanks.

  (d) At least two (2) pumps shall be provided in each lift station. Pumps shall be of the same capacity. Each shall be capable of handling at least the expected maximum flow to the lift station.

  (e) Controls other than float switches shall:

(1) be installed outside the lift station;

(2) comply with the Indiana Electrical Code (675 IAC 17); and

(3) include automatic pump alternators.

Encapsulated mercury float type switches are preferred over other types. Motor controls shall be protected by a conduit seal or other appropriate measures to exclude moisture from the wet well. Power cords shall meet the requirements of the Mine Safety and Health Administration for trailing cables. Ground fault interruption protection shall be used to de-energize the circuit in event of any failure of the cable.

  (f) An audio-visual alarm system shall be provided to indicate power failure, pump failure, excessive water level or any cause of pump station malfunction. The alarm shall be:

(1) located in an area where it can be observed twenty-four (24) hours a day; and

(2) powered by a circuit separate from the pump circuit.

  (g) Overflows from lift stations are not permitted.

  (h) Pump discharge lines shall include suitable shutoff and check valves. Check valves shall be located between the pump and the shutoff valve and only in the horizontal portion of the line. Check valves should be omitted in discharge lines connected individually to pumps where the lines must drain back into the pump station wet well between pumpings.

  (i) Force mains should be sized to provide a scouring velocity of at least two (2) feet per second at the design capacity of the pump.

  (j) Automatic air relief valves shall be installed at high points in the force main to prevent air locking.

  (k) Separation distances between sanitary force mains and water lines shall be the same as required for gravity sewers. A ten (10) foot horizontal separation is required between parallel water lines and force mains, and an eighteen (18) inch vertical separation is required where force mains cross water lines.

  (l) Force mains crossing other properties will have to be kept accessible through construction and maintenance easements. (Indiana State Department of Health; 410 IAC 6-10.1-67; filed Oct 19, 2012, 2:07 p.m.: 20121114-IR-410120157FRA)