Pipe Bursting
Over the next 12 years, the City of Atlanta will inspect,
repair and where necessary, replace every foot of the 2,200
miles of sanitary sewers. This unprecedented $1.2 billion
project is an integral part of the City’s comprehensive
efforts to meet and surpass all federal and state water quality
standards.
The successful completion of the Clean Water Atlanta projects
will benefit Atlanta’s citizens and ratepayers, and
our neighbors downstream and throughout the region by providing
the infrastructure necessary to improve water quality and
sustain Atlanta’s economic vitality.
The SSES project is the first step in bringing Atlanta’s
aging sewer system up to world class/modern-day standards
and protecting Atlanta ratepayers’ quality of life by
eliminating Sanitary Sewer Overflows (SSOs). Through the efforts
of the SSES, approximately 60,000 manholes and 2,200 miles
of sanitary sewers will be inspected for cracks, collapses,
and blockages. After extensive investigation and documentation
of defects is completed, a rehabilitation plan will be developed,
identifying necessary sewer repairs and replacement. In severe
situations, immediate repair may be required.
This document explains a method of sewer rehabilitation known
as Pipe Bursting that may be used during the SSES project.
It also outlines what you might expect during the project.
What is pipe bursting?
Pipe bursting is a method for inserting a new plastic pipe
of equal or larger diameter into an existing pipeline by bursting
open the existing pipe and pulling or pushing the new pipe
into the old pipe and expanded surrounding soil. The new pipe
is simultaneously inserted into the enlarged hole created
by the burster (or expander). This concept was first developed
in Europe to replace cast-iron, gas-distribution pipes with
minimum impact to surface improvements. Pipe bursting has
been used in the United States since 1986 for rehabilitating
up to one million linear feet of pipe per year. The following
figure provides a schematic view of the process of pipe bursting.
What conditions allow for pipe bursting methods
to be used?
Typical pipe diameters for this method range from 4 inches
to 36 inches, though pipes as large as 42-inches have been
burst. Pipe bursting is suitable for replacing pipes made
of brittle material such as vitrified clay, un-reinforced
concrete, asbestos cement, some polyvinyl chloride (PVC),
and cast iron. It is less appropriate for the replacement
of steel, ductile iron, reinforced concrete pipes, polyethylene
(PE) pipes, or composite, though methods for pre-cracking/splitting
and then bursting these pipe materials are being developed.
Bursting progress of 2 to 10-feet per minute is possible.
 
What are the benefits of pipe bursting?
Pipe bursting has several advantages over open-cut trenching
and other trenchless rehabilitation methods:
- Pipe bursting allows for replacement of pipes without
disturbing surface structures.
- Potential problems with existing pipes are minimized because
pipe-bursting methods follow the existing pipe path.
- For smaller sizes of pipe, pipe bursting is the only
trenchless technology that can be used to upsize the existing
pipe.
- Because it is trenchless, excavation is minimized, which
lessens effects on existing landscaping and structures.
The bursting heads on the piercing tool can be removed at
the end of the line so that the tools may be removed through
the new line. This can eliminate the need for an exit pit
in some instances.
- Pipe bursting reduces the amount of site restoration required.
Why does the City need access to my property for
180 days?
The actual process of pipe bursting will likely take less
than one day to complete. However, there are several activities
that may require access to property to ensure rehabilitation
is successfully completed; these activities include the following:
1. Planning and logistics for construction purposes.
2. Inventory of fences, trees, etc. that may impede free
access for construction/maintenance equipment.
3. Determine location of proposed cleanouts and existing
private service connections to main sewer.
4. Assess logistics to disconnect/reconnect service connections.
5. Conduct soil testing as needed.
6. Perform landscaping pre-construction survey and protection
plan and post pipe bursting restoration plan and work.
7. Pre- and post-pipe bursting building surveys (internal
and external).
8. The management of flows from property – planning
and actual maintenance of flows.
9. Dye testing to confirm abandoned as opposed to active
connections as well as connectivity between buildings and
sewers.
10. Meet with property owner to address questions and to
obtain permission to access sewer through property, where
required.
For additional SSES Project information, please
call the CWA Hotline at 404.529.9211
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