SMALL DAMS PETITS BARRAGES

Destruction and
Replacement
New Pipe
Installation
PIPE
BURSTING
AND PIPE
SPLITTING
PIPE EATING
HORIZONTAL
DIRECTIONAL
DRILLING
MICRO-
TUNNELING
Conditions Pros Cons Comments
shapes.
varied using optional curing 3. Closed-circuit television
techniques.
inspection will be required
immediately
renovation.
prior to
1. May be partially blocked; 1. It can replace existing pipe 1. This method must be This method is most useful for
existing structural capacity with larger diameter pipe. modified by adding pipe increasing existing pipe
should be less than the
splitting techniques to repair diameters. If they are
bursting forces.
2. Existing pipe is broken non-brittle pipe.
deteriorated or not. Careful
and left surrounding the new
consideration should be taken
pipeline.
2. This technique may not in determining if this technique
burst reinforced or previously will be able to burst the existing
repaired pipelines.
pipe.
2. Common diameter is
305 mm (12 in.), yet up to
1 194 mm (47 in.) diameter is
possible.
1. Useful for deteriorated and
unreinforced clay, partially
reinforced concrete, and
highly deteriorated ductile
iron pipe.
2. Any diameter.
1. Appropriate for flexible
polymer pipe installation.
2. Useful for almost any
diameter pipeline.
1. Appropriate for high
compressive strength pipe
1. It allows for upsizing
existing pipe diameters.
2. Existing [pipe materials
are removed from the
ground.
3. Realignment of the newly
installed pipeline is possible.
1. Open trench and pit
excavations may be
eliminated altogether.
2. Flexible pipeline, drilling
machine, and monitoring
instruments allow for
controlled direction and depth
during installation.
1. It can perform
installation of pipe at great
1. Only old clay pipe without
reinforcing, asbestos
concrete with or without
mesh reinforcement and
some highly deteriorated
ductile iron pipe may be
replaced.
2. Substantial insertion and
extraction excavation will be
required.
1. Some drilling machines
require excavations to place
the machine at the desired
pipeline depth.
2. Only flexible pipes, such
as polyethelene or steel, may
be installed with this method.
1. Substantial excavations
will be required for
This technique is useful for
eliminating the need for opentrench
pipeline replacement for
select existing pipe types.
Where applicable, this
technique can be very useful in
upsizing and realigning a new
pipeline.
This technique is most useful
for flexible-type pipe, which
commonly is used for cable and
electric lines. Gravity pipelines
are less common, but are
becoming more common with
the use of direction and depth
monitoring systems.
This technique is useful for
situations where open-
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