Tubercles form inside water mains as a result of corrosion. They consist of layers of rust, building up over time to form lumps and mounds inside the pipe. Tubercles can severely reduce the full flow of water through a pipe. If your water pressure is low or your water is cloudy, it could be caused by tubercles.
In 1983, the City of Richmond Department of Public Utilities created a rehabilitation program for the city’s water pipe system. This Cleaning and Lining Program was designed to improve water quality at a lower cost than replacing existing water mains by drilling out and relining existing water mains with cement mortar.
Neighborhoods targeted for cleaning were the ones that had a high frequency of water pressure complaints, aging pipelines, cloudy water, and a history of water main breaks.
Cleaning and lining was done from spring to fall, so neighborhoods as large as the Fan took four to five years to complete, one section at a time. The project was completed in 2014.