Before rehabilitation techniques can be selected, it is necessary to identify the performance deficiencies of the pipeline. This requires comprehensive, and often costly investigations, particularly when sewers in excess of 48-inch diameter are involved. A major collapse of a 72-inch diameter brick line in 1957 highlighted the potential problems associated with the ageing brick sewers in Seattle. Therefore, following its creation, Seattle Metro launched a comprehensive and continuing inspection and rehabilitation program. This program has included condition evaluation and monitoring, repointing, grouting, and structural lining. The grouting programs have been extensive, and several sections have been grouted more than once.
Television and Scanning Sonar in Seattle Metro’s Siphons and Brick Sewers
Authors: Graham Knott, Roger Browne
1992 PNPCA Conference