PARALLEL INSTALLATION:
| |||||
A building sewer or drain shall not be placed
in the same trench with a water service pipe unless the water pipe
rests on a solid shelf at one side of the common trench and the water
pipe invert is at least 18 inches above the top of the building sewer
or drain and a minimum of five feet edge to edge horizontally. See
Figure 8-1 provided.
| |||||
A water main shall be at least 10 feet horizontally
from any sanitary sewer, storm sewer, sewer manhole, building sewer
or drain. The distance shall be measured edge to edge. See Figure
8-1A provided.[2]
| |||||
CROSSINGS:
| |||||
1.
|
Normal conditions. Water services and mains
crossing house sewers, storm sewers or sanitary sewers shall be laid
to provide a separation of at least 18 inches between the bottom of
the waterline and the top of the sewer whenever possible.
| ||||
2.
|
Unusual conditions. When local conditions prevent
a vertical separation as described above, the following construction
shall be used:
| ||||
a.
|
Nonpotable lines passing under or over waterlines
shall be constructed of materials and with joints that are equivalent
to water main standards of construction and shall be pressure tested
to assure water tightness prior to backfilling.
| ||||
b.
|
Water mains passing under sewers shall, in addition,
be protected by providing:
| ||||
1.
|
A vertical separation of at least 18 inches
between the bottom of the sewer and the top of the water main.
| ||||
2.
|
Adequate structural support for the sewers to
prevent excessive deflection of joints and settling on and breaking
the water mains.
| ||||
3.
|
That one full length of water pipe shall be
centered at the point of crossing so that the joints will be equidistant
and as far as possible from the sewer.
| ||||
3.
|
Variances to the above must be requested, and
approved jointly, through the Code Enforcement Division and the Water
District, where appropriate.
|
(4)
|
No gray water heat recovery unit or similar
device designed to warm potable water by means of bathing or submersion
of potable water supply piping in sewage, wastes or other hazardous
materials shall be installed.
|