Rehabilitation of Wastewater Collection and Water Distribution ...

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Purpose of White Paper
1.0 INTRODUCTION
This White Paper is intended to provide an overview of the current state-of-the-practice and current stateof-the-art
for rehabilitation of pipes and structures within the wastewater collection and water distribution
systems. Rehabilitation is defined as repair, renewal, and replacement of components to return the system
to near-original condition and performance. The document was produced for use as a basis for
discussions in an International Technology Forum, which was held on September 9 to 10, 2008 as part of
the U.S. Environmental Protection Agency (EPA) project Rehabilitation of Wastewater Collection and
Water Distribution Systems (Contract No. EP-C-05-057, Task Order No. 58 [TO 58]). Participants in the
Forum were invited to comment on the descriptions of the state of the water infrastructure technology
industry, provide different viewpoints as appropriate, propose additional issues to be considered, and
present information on specific technological advances underway in North America and elsewhere in the
world. The White Paper and Forum contributions together provide a clear documentation and analysis of
the current status of technology and practice for rehabilitation of water and wastewater pipe systems in
North America and clear guidance on how the demonstration activities planned within the project can best
contribute to advancing the technology and accelerating the adoption of favorable approaches. The key
Forum recommendations are included in this report in Section 8. While there is also an urgent need to
understand system-wide issues in the operation of water and wastewater systems (e.g., the interaction of
wet weather flow with wastewater treatment plant operation), this project and White Paper are focused on
the rehabilitation of the pipe systems themselves.
Development of Rehabilitation Practices
Some aspects of drainage and sewer systems can be dated back at least to 4,000 – 2,400 BC.
Archeological evidence (Schladweiler, 2002) indicates that in the Mesopotamian Empire, during this
period, stormwater drain systems were constructed using sun-baked bricks or cut stone, and clay was
molded to form pipes, tees, and angle joints. A later example (dating from approximately 1,500 – 1,300
BC) of a street drainage channel covered over with a stone slab and clay drainage pipes can be found in
the archaeological excavations at the site of the City of Troy in present day Turkey (Troia, 1999).
In Roman times, both storm and sanitary sewer systems were already in use; water supply systems
involving complex aqueduct systems and lead piping within houses can still be observed in old Roman
settlements. The “dark ages” and even the Renaissance period saw this acquired “know how” disappear,
resulting in dire unsanitary conditions in urban areas in many parts of the world. Urban conditions were
made much worse by the industrial revolution, which brought an influx of poor residents to the cities and
resulted in high-density urban development with little access to fresh water or sanitation. Paris introduced
sewer pipes and tunnels during the 13th century AD. In 1854, John Snow made the connection between
communicable diseases and clean water supply and sanitary conditions in London, which launched a
“modern” wave of construction of better water supply and distribution systems and increased attention to
sewerage needs. However, it took the “great stink” of 1858 along the River Thames to goad the English
parliament into approving the creation of a drainage system to carry the polluted water in tunnels to be
discharged well downstream of the capital city. Improved water supply and sewerage systems quickly
spread to many other cities in the Western world, although effective treatment of collected sewage often
lagged many decades behind the decision to transport and discharge it into receiving waters away from
populated areas. Some of the original systems installed in many cities are still in operation and in good
condition, but many portions of systems (including portions installed only a few decades ago) are in poor
condition and continue to deteriorate.
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