1220-04-03-.26
Standards Of Construction
Cite as Tenn. Comp. R. & Regs. 1220-04-03-.26
(1)
Mains
WATER REGULATIONS
CHAPTER 1220-04-03
(a)
Depths of Mains - Water mains shall be placed at such a depth below ground level, or
otherwise protected, as will prevent freezing during the coldest weather experienced in
the community in which laid, and to prevent damage by traffic.
(b)
Dead Ends - Insofar as practicable, the utility shall design its distribution system so as
to avoid dead ends in its mains. Where dead ends are necessary, the utility shall
provide hydrants or valves for the purpose of flushing the mains. Mains with dead ends
shall be flushed as often as necessary to maintain the quality of the water.
(c)
Segmentation of System - Valves or stopcocks shall be provided at reasonable
intervals in the mains so that repairs may be effected by the utility with interruptions to
the service of a minimum number of customers.
(d)
Disinfection of Water Mains - All new mains shall be thoroughly disinfected before
being connected to the system. The method of disinfecting shall be in compliance with
State Department of Health practices.
(e)
Grid Systems - Wherever feasible the distribution system shall be laid out in a grid so
that in case of breaks or repairs the interruptions of service to the customers shall be at
a minimum.
(2)
Service Pipes
(a)
Size of Service Pipe - The size, design, and material and installation of the service pipe
shall conform to such reasonable requirements of the utility as may be incorporated in
its rules and regulations, provided, however, that the minimum size of the pipe shall not
be less than nominal size except under unusual circumstances which shall be clearly
defined.
(b)
Depth of Service Pipes - All service pipes shall be laid at such a depth as will prevent
freezing, except when services are not intended for use during freezing weather, and
are actually drained during such periods.
(c)
Inspection of Service Pipe - In the installation of a service pipe the customer shall leave
the trench open and pipe uncovered until it is inspected by the utility or other duly
authorized agency and shown to be at proper depth, free from any tee, branch
connection, connection, irregularity, or defect.
(3)
Construction and Maintenance
(a)
Whenever normal excavation discloses unsatisfactory foundation one or more of the
following corrective measures shall be adopted:
1.
Excavate to good bearing soil and backfill to pipe grade with suitable material
well tamped to provide adequate support.
2.
Support with a concrete slab.
3.
Support with piling.
(b)
Pipe on a highway bridge shall be located so as to reduce hazard to a minimum and be
protected from freezing.
(c)
Pipes laid in trench with other facilities.
WATER REGULATIONS
CHAPTER 1220-04-03
1.
All water mains shall be laid clear of all other underground structures and should
not be laid in the same trench with other underground utilities in order to
minimize the possibility of water leakage by reason of any movement of such
structures or of the mains.
2.
Water services may be laid in the same trench with other underground utilities
with the exception of sewer pipes, provided such service pipes are laid at least
twelve (12) inches in a horizontal plane from other subsurface facilities.
3.
At crossings of mains and services with other underground structures clearances
shall be not less than twelve (12) inches.
4.
To secure compliance with the requirements of these rules by others doing
underground construction work, the utility should arrange with the other agencies
having highway subsurface rights for adequate notification and inspection
procedure.
(d)
Pipe laid shall be tested and made tight before being placed in service.
(e)
The ditch underneath, around and over the pipe shall be backfilled with good material
thoroughly tamped to secure a firm support. To disclose any settlement of the backfill
which may need correcting, newly filled ditches shall be reinspected at intervals for
sufficient period of time subsequent to completion of backfilling operations.
(f)
Service connections may be tapped into cast iron mains if the diameter of the hole
does not exceed one-quarter of the diameter of the main. Otherwise, and in mains
other than cast iron, a saddle, sleeve or welded connection may be used or a tee cut
into the line.
(g)
The service connection at the main or the run of service pipe shall allow for a
reasonable amount of flexibility to prevent fractures or leaks at the connection with the
main.