Current through Register No. 13, March 27, 2025
(a) Where
operational pressure is anticipated to be less than 30 pounds per square
inch(psi), the service line shall be oversized so as to reduce frictional
losses.
(b) Maximum system pressure
shall be 100 psi. Any portion of the water distribution piping system where
pressure is expected to exceed 100 psi shall have pressure reducing valves
installed on each individual water service line or on the water main to
maintain pressure at less than 100 psi. Any bypass line around a water main
pressure reducer shall also have a pressure reducer. The water system shall
maintain all pressure reducing devices.
(c) For non-community water systems serving
campgrounds, the following shall apply:
(1)
The water distribution piping system shall be capable of passing peak flow
without excessive frictional loss, such that at peak flow, pressure at each lot
or site shall be at least 20 psi;
(2) Consideration shall be given to possible
future expansion in the sizing and layout of the proposed water distribution
piping system;
(3) The water
distribution piping system shall be so valved as to allow isolation of major
sections of the water distribution piping system for repairs while still
providing service to most of the water system;
(4) The spacing for on-line gate valves
installed on water mains shall not exceed every 1,500 feet, and gate valves
shall be provided at all intersecting pipes;
(5) Blow-offs shall be installed to allow
flushing of the water distribution piping system near the ends of the water
mains, and shall be sized so as to permit high velocities, at least 2.5 feet
per second, to be developed in the water distribution piping;
(6) Where possible, dead-end piping shall be
avoided. Near the temporary end of a water main, a gate valve shall be
installed to allow future piping extension without shutting down the system or
jeopardizing the health of existing consumers;
(7) Water distribution piping shall be bedded
in sand or other appropriate material with a minimum cover of not less than 5
feet for year-round systems;
(8)
Piping and valving material and installation techniques shall conform with the
appropriate American Water Works Association (AWWA) specification, in
accordance with Env-Ws 307, for that type of piping material where such
specification exists. Where such specification does not exist for the size pipe
specified in the system design, the minimum pressure rating for piping shall be
200 psi and the piping shall meet the manufacturing requirements of the
American Society of Testing and Materials (ASTM) specification 2241;
and
(9) All buried non-metallic
piping shall be backfilled with an effective metal tracing element located
above the pipe approximately 6 inches below the finished grade.
(d) Subject to (e), below, if a
water main and sewer pipe are to be installed adjacent to one another, a
minimum horizontal separation of 10 feet shall be maintained.
(e) When conditions prevent 10 feet of
separation, the following shall be considered by the water system:
(1) Where other utilities or obstacles, not
including bedrock, prevent such separation, a waiver may be requested to allow
location of the sewer pipe not less than 3 feet from a water main horizontally,
provided that the water main is in a separate trench or on an undisturbed earth
shelf located on one side of the sewer and at an elevation so the bottom of the
water main is at least 18 inches above the top of the sewer pipe;
(2) If a water main shall cross a sewer pipe,
the water main shall cross above the sewer pipe, with not less than 18 inches
of clear separation;
(3) Water
piping may cross under sewer piping only when this is demonstrated to be
unavoidable and only when granted by specific waiver. Special construction,
including use of ductile iron water and sewer pipe, no pipe joints within 9
feet of the crossing points, and minimum 18 inches clearance shall be required;
and
(4) Technical criteria
supporting a waiver of sewer pipe and water main separation criteria shall
include:
a. The topography of the area;
and
b. The number of utility
interferences.
(f) Other utilities,
including, but not limited to natural gas, storm
drainage, electric, telephone, steam, and cable television, shall not be
installed within 3 feet of water mains.
(g) On-line gate valves and service shut-offs
shall be equipped with cast iron gate box extensions. Gate valve boxes shall
have cast iron covers clearly marked by the word "water" or other appropriate
water supply marking and shall be installed flush with the finished
grade.
(h) Rigid connections shall
not be used to construct or repair water distribution piping systems.
(See Revision Note at chapter heading for Env-Ws 300); ss
by #8499, eff 11-30-05