Gibbs Station 1-CS 921102TOPS gFORM 4151
(c)
~-~
Locati~
needed to maintain water quality.
of mains.
(1)
When new water mains and new sanitary sewers are installed,
they shall be installed no closer to each other than 9 feet
in all directions and parallel lines must be installed in
separate trenches. Where the 9 foot separation distance
cannot be achieved, the following procedures shall be used.
(A)
Where a new sanitary sewer force main parallels the
water main, the sanitary sewer shall be constructed of
cast iron, ductile iron, or PVC pipe meeting AWWA
Specifications, having a minimum working pressure
rating of 150 psi or greater, and equipped with pres-
sure type joints. The water main and'sanitary sewer
shall be separated by a minimum vertical distance of
two feet, and a minimum horizontal distance of four
feet, measured between the nearest outside diameters of
the pipes, and the water main shall be located above
the sewer.
.005. Water Distribution. (Cont.)
(B)
(c)
(D)
Where a new gravity, sanitary sewer parallels a new
water main, the sanitary sewer shall be constructed of
cast iron, ductile iron, or PVC pipe meeting AWWA
Specifications, or having NSF approval for use as
potable water pipe, with a pressure rating for both the
pipe and the joints of greater than or equal to 100
psi. The new water line may be placed no closer than
two feet vertically and four feet horizontally from the
sewer, with the separation distances measured between
the nearest outside pipe diameters. The water main
shall be installed at a higher elevation than the
sanitary sewer.
Where a new sanitary sewer crosses the water main, and
that portion of the sewer within 9 feet of the water is
constructed as described in .005(c)(1)(B), the water
line may be placed no closer than 6 inches from the
sewer. The separation distance must be measured
between the nearest outside pipe diameters. The water
line shall be located at a higher elevation than the
sewer wherever possible and one length of the sewer
pipe must be centered on the water line.
Where a new sanitary sewer crosses under the Water
main, and the sanitary sewer is constructed of ABS
truss pipe, similar rigid plastic composite pipe, clay,
or concrete pipe with gasketed Joints, the water main
shall be placed no closer to the sewer thantwo feet,
measured between the nearest outside diameters, provided
the initial backfill zone of the sewer trench is backfilled
with well mixed cement stabilized sand (2 or more bags
of'cement per cubic yard of sand) in the initial backfill
'zone of the trench, for all sections of sewer within 9
feet of the water line. The initial backfill zone of
the trench is defined as extending from a point one-
fourth pipe diameter above the bottom of the pipe to an
elevation in the trench which is one pipe diameter (but
not less than 12 inches) above the top of the sewer