Public Utilities
A "Pipeline" to the Future
Folded pipe debuts in Portsmouth

Portsmouth is a historic seaport city with a rich maritime history. Parts of Portsmouth's sanitary sewer system mirror the city's history. These older sewers may show their age with blockages and failures that can result in sewage backups and overflows and even cave-ins that can effect the condition of the streets above.

Clay Pipe Woes
Clay pipe was the material of choice for sewer lines in the U.S. for many years. Portsmouth used it from 1890 until 1972. While very resistant to sewage and gases, clay pipe can have joint problems. Its brittleness can cause pipe failures in wet, shifting soil conditions. Until recently replacement was the one sure way to fix failing clay pipes. This was costly as the overlying street would have to be torn up and replaced along with the pipe!

Rehab Uses Folded Pipe
A new rehabilitation technique using PVC pipe is being used in Portsmouth. Folded into a "U" shape for easier insertion, long lengths of PVC pipe are pulled into the clay sewers through manholes. Heat and pressure are applied to the PVC and it returns to its round shape, tightly hugging the old clay pipe, providing strength and restoring the sewer. 4,000 feet of sewer mains on Allard Road, London Boulevard, Washington Street, Bolling Road and Green Street have been restored using the folded "U" shaped liner. It has proven to be a cost effective and reliable way to restore clay sewers. Folded liner restoration is up to 50% lower in cost than total replacement.

Folded Liner

Expanded Liner

Lining makes good $ense

Maintaining Portsmouth's 350 miles of sanitary sewer lines can be costly. That is why our Department of Public Utilities is putting new technology to work to reduce cost and extend the impact of its maintenance dollars. The use of "no dig" methods like the folded sewer liner featured in this article are one way Public Utilities is using good $ense to benefit the citizens of Portsmouth.