York-Peel Feedermain Emergency Repairs

The York-Peel Feedermain provides approximately 30% of the water supply for the Regional Municipality of York (the Region) and consists of an 1,800-millimetre-diameter prestressed concrete cylinder pipe. During a routine leak detection inspection using SmartBall technology, the Region discovered two leaks. One was severe, at an estimated 30 litres per second and located directly beneath the Humber River within an environmentally sensitive area. Swift action was needed to address the issue before the peak spring water demand to ensure continued uninterrupted service to the community.    

In collaboration with TYLin and Robinson Consultants Inc., the Region selected carbon fiber reinforced polymer (CFRP) lining as the optimal solution. This project marks the first use of CFRP in the Region. The decision followed our comprehensive review of available technologies for similar-sized transmission mains, the water main’s operating pressure and geometry, available access points, minimal environmental disruption, and an expedited project schedule.  

CFRP’s advantages include the option for spot repairs, the ability to maintain internal pressure up to 350 psi, and minimal environmental impact. It involves applying layers of carbon fiber fabric coated with a polymer resin to strengthen and repair structures from within. CFRP provides several benefits, including a high strength-to-weight ratio, corrosion resistance, and excellent fatigue performance.  
 
Completing this repair within the given time limit was critically important to minimizing stress on the existing water supply system. Selecting the appropriate technology and assembling team members skilled in this application were also key to project success.  

The Region, TYLin, and the contractor worked together to develop the work plan needed to decommission the feedermain, inspect the condition, design the repair, complete the repairs, and recommission the feedermain in only six months. Traditional repairs would have taken one to two years. 

Project Highlights:

• A total of 370 metres of feedermain was rehabilitated using CFRP. 
• The project required extensive consultation with the Toronto Regional Conservation Authority. 
• During the draining of the feedermain, about 18,000 cubic metres of water was neutralized using sodium thiosulphate before being pumped into energy dissipation pools and monitored to ensure no adverse impacts to the nearby Humber River systems. 
• At peak, crews efficiently applied 61 metres of two-liner thickness per day.  
• We developed a site-specific Project Safety and Emergency Response Plan with zero health and safety incidents reported.  
• The team kept the community informed on progress and impacts, using portable message boards and signs to advise of lane and trail closures.