Potable water is water from a public or private water supply system
or source which is accepted by the proper governing authority as suitable
for human consumption.
No potable water, when such use is specifically approved by proper administrative
authority, may be used for flushing water closets, urinals and other purposes
not requiring potable water, provided only that such water shall not be readily
accessible for drinking purposes. All piping conveying nonpotable water shall
be adequately and durably identified by a distinctively colored paint so that
it is readily distinguished from piping carrying potable water.
Potable and nonpotable water supplies shall be distributed through a
system entirely independent of each other, and any cross-connection between
such supplies is prohibited.
No cross-connection or interconnection of pipes, valves or other devices
which connect the water lines of the City to and with pipes or fixtures supplied
with water from any other source shall be made or permitted at any time except
in strict compliance with the rules and regulations of the Board of Public
Works and not until a signed permit has been issued by the Superintendent
of said Board.
Wherever possible, water service and house sewer should be laid in separate
trenches. Where they must be laid in the same trench, the water pipe shall
be laid on a bench or on solidly tamped backfill at least 12 inches above
the top of sewer pipe.
The water distributing system shall be protected against backflow, preferably
by having the outlet end from which the water flows spaced a distance from
flood-level rim of the receptacle into which the water flows sufficient to
provide a minimum required air gap as defined in American Standard for Air
Gaps in Plumbing Systems (ASA, A40-4, 1942). Where it is not possible to provide
a minimum air gap, the fixture shall be equipped with an accessibly located
backflow preventer, complying with the American Standard Backflow Preventers
in Plumbing Systems (ASA, A40.6), installed between the control valve and
the fixture or outlet.
Where it is not possible to provide a minimum air gap or backflow preventer,
as may be in the case in connections to cooling jackets, condensers or other
industrial or special appliances, then the governing authority shall require
a separate tank supply or such other means of protection as may be practicable
and desirable.
All nonpressure, potable water supply tanks shall be properly covered
to prevent entrance of foreign material into water supply. Soil or waste lines
shall not be permitted to pass directly over such tanks or over manholes in
pressure tanks.
All piping, tanks, appliances and devices subject to freezing temperature
shall be effectively protected against freezing.
If the discharge or waste from pressure tanks, boilers and relief valves
is connected by piping to the drainage system, it shall be connected as an
indirect waste.
Materials for water distributing pipes and tubing within a building
shall be of brass, copper, galvanized wrought iron or steel, lead or cast
iron, galvanized malleable iron fittings. Copper water tube and soldered fittings
shall conform to ASA Specifications H23.1-1947 and A40.3-1941.
Piping material that has been used for other than potable water supply
shall not be used in a potable water supply system.
When selecting the material and size of pipe for water supply, due consideration
shall be given to the action of the water on the interior of the pipe and
of the soil, fill or other material on the exterior of the pipe.
A. All water services shall be of Type K copper and the
minimum size shall be 3/4 of an inch, with inverted stop-waste cocks
for curb cock and house stop. Curb box shall be of an approved type, and only
flared fitting shall be used.
B. All other water services and water mains will be allowed
only with the approval of the Commissioner of Public Works.
Where flush valves are used or other devices requiring relatively high
rates of flow of water, the water service pipe must be designed to supply
this flow.
Separate stopcocks or valves, always accessible, shall be placed at
the foot of each riser line, and, in multiple dwellings or commercial buildings,
a valve to control each dwelling unit.
All water pipes shall be so graded or pitched that the entire system
or parts thereof can be drained. The formation of traps and sags shall be
avoided where possible, or provisions made for draining.
Supply lines taken from pressure or gravity tanks shall be valved at
or near their source.
Individual controls shall be provided for all water closets and for
any fixture isolated from a group.
[Amended 12-12-1973]
House tanks shall only be allowed with the approval of the Commissioner
of Public Works as to where required, design, as to inlet and air gap, contamination
and valves, and shall not be allowed to be connected directly to any drainage
system. Inlet and outlet valves shall be of the same size.
All plumbing fixtures shall be provided with an adequate supply of water
for flushing so that they may not become foul, unsanitary or dangerous to
health. Every water closet or pedestal urinal shall have an approved tank
or valve of at least six gallons flushing capacity for water closets and at
least two gallons for urinals, and shall be adjusted to prevent the waste
of water.
The minimum size of water supply pipes to fixtures shall be as follows:
Fixture
|
Pipe Size
(inches)
|
---|
Water closet and urinal tanks
|
3/8
|
Flush valves for water closets, siphon-jet, blowout and pedestal urinals
|
1
|
Lavatories
|
1/2
|
Bathtubs
|
1/2
|
Shower stalls
|
1/2
|
Sinks
|
1/2
|
Laundry tubs
|
1/2
|
Combination sink and tray
|
1/2
|
Service sink
|
1/2
|
Flushing rim sinks
|
3/4
|
Drinking fountains
|
3/8
|
Sill cocks
|
1/2
|
Hot water boilers
|
1/2
|
Self-closing devices shall be provided with air chambers or shock absorbers.
Where circulating hot water supply systems are installed, the hot water
pipes should be covered with approved insulating material.
A suitable pressure relief valve shall be installed on the hot water
storage tank or at some point in the hot water supply system. Such relief
valve shall be so located that there is no shutoff valve between the heating
boiler or device and the relief valve.
An approved temperature relief valve conforming to the requirements
of the American Standard Listing Requirements for Relief and Automatic Gas
Shut-Off Valves for Use on Water Heating Systems. (ASA, Z21.22) shall be installed
on the hot water storage tank to prevent the storage of hot water at a temperature
higher than boiling point at atmospheric pressure.
Any relief valve that meets the specifications of the National Board
of Casualty and Surety Underwriters shall be considered acceptable. All relief
waste from valves shall be run as an indirect waste.
All water service pipes shall be run in such manner with enough slack
and play to allow for the working of the ground, and each corporation cock
shall have a brick house protection.
All service pipes shall be protected from frost and shall be at least
four feet underground. If less, they shall be wrapped with felt and tar paper
securely fastened with brass bands or copper wire.
All new water service pipes shall be tested in the presence of the Inspector.
All excavations for water services and sewers shall be backfilled in
street and sidewalk areas with gravel.
Where there is danger of contamination of the water supply, or where
such contamination actually develops, the fixtures, apparatus or piping shown
to be responsible for the condition shall be altered or replaced to conform
to the requirements of this chapter.
Wherever the supply to a fixture is introduced into such fixture below
the overflow level, such supply shall be provided with an approved vacuum
breaker which will prevent the siphoning of water from such fixture into the
supply piping.
Direct water supply piping connections to sterilizers are prohibited.
The water piping for sterilizers shall not be connected directly with any
drainage system; such waste piping shall discharge above an open, water-supplied,
trapped and vented fixture.
Under no condition shall used pipe be used on any part of the water
system.