Structural and Operational Review of Regional Trunk Sewers
In the mid 1990's, the Environmental Technical Services (ETS) section began a comprehensive assessment of the trunk sewers within the Regional jurisdiction.
Closed circuit television technology is used to inspect the sewer mains. A T.V. camera is either pulled from manhole to manhole or is placed upon a small crawler and driven through the pipe. Images are streamed to video tape as a record of both the structural condition of the pipe and its operating efficiency.
There are approximately 100 kilometres of trunk sanitary and combined sanitary/storm sewers currently within the Niagara Region's jurisdiction. The average diameter of the regions sanitary truck system is 900mm with the largest pipe being 1825mm. Approxiately 26 kilometres of pipe are logistically and technically very difficult to access for inspection.
These challenges include extreme depth (up to 22 metres below ground level), toxic gases such as hydrogen sulfide, and very high flows and pipe slopes that the camera crawler cannot negotiate. New technologies are currently becoming available that may allow for inspection of these problem locations. These technologies include towed sonar and alternative camera platforms. ETS has (and will continue to) experiment with these technologies to ensure that all infrastructure within the Regional jurisdiction is assessed on a regular basis.
Partially collapsed sanitary sewer pipe found during CCTV inspection of Regional trunk sewer mains. This is an example of an acute structural deficiency that must be addressed rapidly to assure the continuing operation of the sewer system. The pipe was immediately replaced.
Heavily infiltrating joint within a sanitary sewer. Millions of litres of ground water and rain water can enter a poorly maintained sewer system, adding significantly to operating costs, and robbing the system of capacity. This sewer was repaired using 'no-dig' or 'trenchless' technology, greatly reducing repair costs through conventional means.
For more information about this program, please contact Kyle Moate.