Current through Register Vol. 49, No. 13, September 23, 2024
Subpart
1.
General.
Pumping stations must be designed to maintain the sanitary
quality of the water being pumped. All raw or finished water pump stations
must:
A. provide space to access and
service all equipment;
B. have
outward opening doors;
C. have a
floor elevation at least six inches above the finished grade and at least 24
inches above the regional flood level. Below grade installations shall be
permitted only if the terrain at the site is such that a gravity drain system
can be provided;
D. have all floors
drained without impairing the quality of water being handled; and
E. provide a suitable outlet for drainage
from pump glands without discharging onto the floor.
Subp. 2.
Pumping station suction
well.
Suction wells, including installations where the pumps are
installed on top of a reservoir, must:
A. be watertight;
B. have bottoms sloped to permit removal of
water and entrained solids;
C. be
vented by means of a pipe or other device terminating in a screened U-bend at
least 24 inches above the floor; and
D. have curbs a minimum of four inches around
all access openings, pipes, and other equipment which extend through the top of
the suction well. Access openings must have covers which overlap at least two
inches.
Subp. 3.
Pumping station pumps.
Pumping stations must:
A. have at least two pumping units except
where additional pumping stations which can meet the peak demand are available
or where the commissioner determines that ample time will be available between
pumping periods for necessary repairs. If only two units are provided, each
must be capable of carrying the peak demand. If more than two units are
installed, each must have sufficient capacity so that any one pump can be taken
out of service with the remaining pump capable of carrying the peak
demand;
B. have controls for proper
alternation where two or more pumps are installed. Provision must be made to
prevent operation of the pump during the backspin cycle. All electrical
controls must be located above grade;
C. provide a power supply from at least two
independent sources or from a standby, auxiliary power source; and
D. provide a prelubrication line with a
valved bypass around the automatic control and backflow protection where
required, whenever automatic prelubrication of pump bearings is necessary and
an auxiliary power supply is provided.
Subp. 4.
Pumping station suction
lift.
A suction lift shall be allowed only for distances of less than
15 feet and where provision is made for priming the pumps. A suction lift shall
not be permitted if used with buried piping carrying finished water.
Subp. 5.
Pumping station
priming.
Prime water must not be of lesser sanitary quality than that of
the water being pumped. Means must be provided to prevent backflow. When an
air-operated ejector is used, the screened intake must draw clean air from a
point at least ten feet above the ground or other source of contamination,
unless the air is filtered by apparatus approved by the commissioner. Vacuum
priming may be used.
Statutory Authority: MS s
144.383
