Section 890.180 Sewer and Water Pipe Installation

Section 890

Section 890.180  Sewer and

Water Pipe Installation

a)         Trenching and Bedding.  Trenches shall be of sufficient width

to permit proper installation of the pipe.  If shoring is required, ample

allowance shall be made in the width of the trench for working conditions,

based on the materials and installation methods.  If trenches are excavated to

a depth so that the bottom of the trench forms the bed for the pipe, solid and

continual bearing between joints shall be provided and bell holes shall be

provided at points where the pipe is joined.  If trenches are excavated to a

depth so that the bottom of the trench does not form the bed for the pipe, the

trench shall be backfilled to the grade of the pipe with sand or fine gravel

placed in layers of 6 inches maximum depth and compacted after each placement.

The pipe shall not be supported on blocks.  If rock is encountered in

trenching, it shall be removed to a point at least 3 inches below the grade

line of the trench; the trench shall be backfilled to grade with the sand

tamped in place to provide a uniform bearing for the pipe between joints.  The

pipe shall not be allowed to rest on rock at any point.  If soft materials of

poor bearing qualities are found at the bottom of the trench, stabilization

shall be achieved by over-excavating at least 2 pipe diameters and refilling

with fine gravel or sand or a concrete foundation.  A concrete foundation shall

be bedded and sand tamped in place to provide a uniform bearing for the pipe

joints.  All piping in the ground shall be laid on a firm bed for its entire

length.

b)         Backfilling.  Trenches shall be backfilled until the crown of

the pipe is covered by at least 18 inches of tamped earth to ensure that the

pipe beneath is secure.  Loose earth that is free of rocks, broken concrete,

frozen chunks or other rubble shall be carefully placed in the trench in 6 inch

layers and tamped in place

the ground shall be laid on a firm bed for its entire

length.

b)         Backfilling.  Trenches shall be backfilled until the crown of

the pipe is covered by at least 18 inches of tamped earth to ensure that the

pipe beneath is secure.  Loose earth that is free of rocks, broken concrete,

frozen chunks or other rubble shall be carefully placed in the trench in 6 inch

layers and tamped in place.  The backfill under and beside the pipe shall be

thoroughly compacted to ensure that the pipe is properly supported. Backfill

shall be placed evenly on both sides of the pipe and tamped to retain proper

alignment.

c)         Breakage and Corrosion.  Pipes passing under or through walls

or floors shall be protected from breakage caused by stress or strain. Pipes

passing under or through cinder, concrete or other corrosive material shall be

protected from external corrosion, stress or strain by a protecting sleeve or a

wrap-on material.  (See Appendix B.Illustration AA.)

d)         Sleeves.  In exterior walls or floors, the annular space

between sleeves and pipes shall be filled or tightly caulked with a cold tar,

asphalt compound or other equally effective material.  (See Appendix B.Illustration

AA.)

e)         Buried Piping Parallel to Footings.  No buried piping shall be

laid parallel to inside or outside footings, closer than 18 inches to the

footing. (See Appendix B.Illustration BB.)

f)         Depth.  Piping installed parallel to footings or bearing walls

shall not extend below the 45 degree bearing plane of the wall or footing. (See

Appendix B.Illustration BB.)