• Client Project A
• Client Project B
• Client Project C

Client Project C

Wet weather flows to the client's wastewater treatment plant exceeded the hydraulic capacity of this facility. While the City anticipates the diversion of these excessive flows to a proposed wastewater treatment plant, efforts to reduce rainfall dependent infiltration/inflow (RDi/i) would mitigate hydraulic overloads until plant construction can be completed. Interra Hydro was selected to conduct a field investigation identifying sources of collection system leaks in the sanitary sewer collection system.

The field investigation incorporated the standard collection system defect identification techniques along with a defect database linked to the City’s ArcView GIS system for customized reporting capability. Some of the tasks associated with the project were:

• Historical data review
• Flow monitoring
• Smoke testing
• Manhole inspection
• Pipe lamping (with digital image recording)
• Closed-circuit televising
• Database development and population
• Graphic representation of defect information

As the investigation of each sub-area was completed, Interra Hydro provided the City’s Engineering Department with manhole and mainline asset and defect information in a Technical Memorandum. This step-wise approach allowed the engineers and in-house construction crews to address defects within each sub-area in a quick and timely manner.

The scope of this project also included Interra Hydro training City personnel assembled from the various collection system and operations departments to form an elite team of in-house field investigators. Further analysis of the remaining basins will be accomplished as rehabilitation efforts migrate across the City.

Customizable reporting capability, links to the ArcView GIS application, and the shared network functionality has made the sanitary sewer rehabilitation program for the City a success for all departments.