Asset Inspection and Assessment

case study: trunk sewer assessment program

The Region of Peel is centrally located in the Greater Toronto Area and encompasses the Cities of Mississauga, Brampton and Caledon. The Region provides wastewater collection and treatment services for 1.4 million residents and 140,000 businesses. Andrews.engineer (A.E) was retained by the Region to carry out a multi-year, phased trunk sewer inspection and condition assessment program to identify short and long-term rehabilitation needs.

All inspection and field investigation services were provided by A.E. This included planning, co-ordination, and execution of CCTV, Sonar and Laser profiling surveys and maintenance hole (MH) inspections. The 5-year program included the following activities:

• Inspection of 250,000 m of trunk sanitary sewers (750 mm to 3050 mm diameter)
• Inspection of 875 manholes and special diversion/control chambers
• Sonar inspection of approximately 15 siphon locations (each including multi-barrel installations)
• Concrete coring and material testing at select locations
• Hydraulic performance evaluation at identified hot-spots

A.E compiled, analyzed and evaluated inspection findings; identified trends and prepared detailed annual inspection reports. These reports provided rehabilitation recommendations including suggested techniques as well as timing and budget estimates. Inspection findings were reviewed and translated into condition grades based on the WRc condition rating scheme. A detailed system atlas illustrating condition assessment results for both sewers and MH for the entire 250 km system was also produced. This Atlas is used by the Region of Peel for ongoing planning and project programming.