Stormwater Manual - Pima County Flood Control District

Pipe bedding shall meet the requirements set forth in the Kentucky Highway Department
Standard Specifications for Road and Bridge Construction, latest edition, and the LFUCG
Standard Drawings, latest edition.
The pipe trench shall be overexcavated six (6) inches and properly backfilled prior to laying
pipe. In no case shall pipe be laid on solid or blasted rock.
Pipe bedding material shall be placed in six (6) inch loose lifts and compacted to 95 percent
maximum dry density at ± 2 percent of the optimum moisture content.
When the subgrade is found to be unstable or to include ashes, cinders, refuse, organic
material, or other unsuitable material, such material shall be removed to the depth ordered by
the Design Engineer and replaced under the directions of the Design Engineer with clean,
stable backfill material. When the bottom of the trench or the subgrade is found to consist of
material that is unstable to such a degree that, in the judgment of the Design Engineer it
cannot be removed, a foundation for the pipe and/or other appurtenance shall be constructed
using piling, timber, concrete, or other materials as the direction of the Design Engineer.
All pipe shall be laid with ends abutting and true to the lines and grades indicated on the
Drawings. The pipe shall be laid straight between changes in alignment and at uniform grade
between changes in grade. Pipe shall be fitted and matched so that when laid to grade, it will
provide a smooth and uniform invert.
The pipe shall be thoroughly cleaned prior to placement. Any piece of pipe or fitting which
is known to be defective shall not be laid. If any defective pipe or fitting shall be discovered
after the pipe is laid, it shall be removed and replaced with a satisfactory pipe or fitting.
The interior of the pipe, as the work progresses, shall be cleaned of dirt, jointing materials,
and superfluous materials of every description. When laying of pipe is stopped for any
reason, the exposed end of such pipe shall be closed with a plug fitted into the pipe bell so as
to exclude earth or other material. Other precautions shall be taken to prevent flotation of
pipe by runoff into trench.
All pipe shall be laid starting at the lowest point and installed so that the spigot ends point in
the direction of flow.
All joint surfaces shall be cleaned immediately before jointing the pipe. The bell or groove
shall be lubricated in accordance with the manufacturer’s recommendation. Each pipe unit
shall then be carefully pushed into place without damage to pipe or gasket. All pipes shall be
provided with home marks to insure proper gasket seating. Details of gasket installation and
joint assembly shall follow the direction of the manufacturer’s of the joint material and of the
pipe. The resulting joints shall be watertight and flexible. No solvent cement joints shall be
allowed.
STORMWATER MANUAL 10-26 January 1, 2009
LEXINGTON-FAYETTE CO., KY.