Nevada Administrative Code › Chapter 445A - Water Controls › PUBLIC WATER SYSTEMS › Design, Construction, Operation and Maintenance › Section 445A.67025 - Pumping facilities: Suction piping

Current through June 11, 2024
1. Except as
				otherwise justified by an engineer and approved by the Division or the
				appropriate district board of health, a supplier of water shall ensure that,
				with regard to the suction piping of the public water system:
(a) The velocity of water in the piping is in
				compliance with the specifications and recommendations of the manufacturer of
				the pump and Standard
				9.6.6 of the American National
				Standards Institute and Hydraulic Institute, as adopted by reference in NAC
				445A.6663.
(b) The diameter of the piping is sized in
				compliance with the specifications and recommendations of the manufacturer of
				the pump and Standard
				9.6.6 of the American National
				Standards Institute and Hydraulic Institute, as adopted by reference in NAC
				445A.6663.
(c) The reducer between the piping and the
				pump is an eccentric reducer and not a concentric reducer.
(d) A fitting is installed between the inlet
				valve and pump which will allow easy removal of the pump. For pumps in suction
				lift, unions must not be used, and valves, except for foot valves, must not be
				installed on suction lines.
(e)
				There is a continuous slope up from the surface of the water to the pump. The
				suction line must be as straight as possible, and the restriction of suction
				must be minimized.
(f) If there is
				a valve on the suction line, except as otherwise provided in subsection 2,
				there is installed between the valve and the pump, preferably on a spool, a
				permanent pressure gauge that:
(1) Operates
				within the appropriate range of pressure; and
(2) Is equipped with a pet cock or ball
				valve. Except when the gauge is being read, the pet cock and ball valve must
				remain closed.
(g) If
				elbows are required in the suction line, the elbows are designed in compliance
				with the specifications and recommendations of the manufacturer of the pump and
				Standard 9.6.6 of the American National
				Standards Institute and Hydraulic Institute, as adopted by reference in NAC
				445A.6663.
(h) Each inlet of a suction pipe in a suction
				well or clear well is:
(1) Bell-shaped in such
				a manner as to reduce head loss at the entrance. Square-cut inlets are
				prohibited.
(2) Adequately
				submerged, in accordance with the specifications of the manufacturer, at a
				depth of at least six times the diameter of the pipe.
(3) Located away from:
(I) The floor of the suction well or clear
				well at a distance specified by the manufacturer of the pump or, in the absence
				of such a specification, at a distance of not less than four nor more than five
				times the diameter of the pipe.
(II) The sidewall of the suction well or
				clear well at a distance specified by the manufacturer of the pump or, in the
				absence of such a specification, at a distance of not less than one-half the
				diameter of the pipe nor more than the diameter of the pipe.
(i) If an inlet screen
				is installed:
(1) The inlet screen is
				designed in such a manner that an adequate flow can enter the pump when half of
				the screen is plugged.
(2) The
				diameter of the screen inlet is at least three times the diameter of the
				suction pipe inlet.
(j)
				If a foot valve is used, the diameter of the foot valve is at least 2 inches
				greater than that of the inlet piping.
(k) If a pump is connected to a header used
				for suction:
(1) The connection is at an angle
				relative to the header of not less than 30 degrees nor more than 45 degrees;
				or
(2) If it is necessary to
				connect the pump to the header at an angle of 90 degrees, the pump is located
				away from the header at a distance in compliance with the specifications and
				recommendations of the manufacturer of the pump and Standard
				9.6.6 of the American National
				Standards Institute and Hydraulic Institute, as adopted by reference in NAC
				445A.6663.
(l) If a pump is in suction head, a valve is
				installed in the suction line to facilitate the removal of the pump for
				maintenance. The valve must not be used to throttle the pump.