Contractor crews from Pure Technologies set up equipment around water main work area

This spring, we started a large-scale infrastructure upgrade project in preparation for future improvements. One of these projects will assess the condition of two of our largest water mains, called “rising mains,” that move water from our Water Treatment Plant in Aspinwall, through the Pittsburgh Zoo, and to the covered reservoir in Highland Park. Our crews have traversed through hillsides and near hyena enclosures as they unearth the 48 and 50-inch mains looking for signs of age.

Sonar tool lowered into the pipe to detect leaks

As work at the Water Treatment Plant and other locations in the distribution system begin in the coming years, the path treated drinking water takes through the system will change. More water will move through the covered Highland Park reservoirs when parts of the system go down for maintenance. For this reason, these large water mains need to be in their best condition to accommodate an increase in flow. To ensure this, crews began with remote-access leak detection through sonar technology by checking the reports for sonar waves. Waves that are longer or higher indicate a leak or air pocket in the pipes. They will also take some camera footage of the inside of the pipes for more data. Finally, in July, the pipes will be drained and experts will do a full visual inspection to look for any cracks or structural deficiencies. 

All this work will eventually inform a design for the repair or replacement of the pipes, depending on their condition. Repair or replacement work is anticipated to take place in 2021. Investigation, design, and construction of these repairs will cost an estimated $23 million and ensure reliable service to our customers as we move on to more large-scale water distribution projects. 

“We are grateful that this project could continue with minimal-to-no delays from COVID-19 due to its importance,” said Executive Director Robert A. Weimar.