The Philadelphia Water Department (PWD)
Pipe Diameter: 16" to 60"
Pipe Type: Cast Iron, Ductile Iron, and Steel
Distance Inspected: 22.2 miles
Service: Sahara® Leak Detection
The Philadelphia Water Department (PWD) has focused on water loss management programs for the past decade and is well known for its annual water audit and for pioneering new methods such as the use of District Metered Areas (DMA) and advanced pressure management. In 2007 PWD also began to use the Sahara® system for precise leak location on its large diameter water transmission mains.
Sahara® pipeline inspections are conducted while the main remains in service by inserting a sensor into any tap 2” or larger. A small parachute uses the flow of water to draw a sensor through the pipeline. The sensor is tethered to the surface, allowing for real-time results, and maximum control and sensitivity. Leaks and other pipeline features can be located above ground to within 18 inches.
In Philadelphia, Sahara® proved particularly useful in scanning two 48-inch diameter steel pipelines that passed under a portion of interstate highway in the city’s downtown core. The pipelines were believed to be suffering from leakage, however because of their underground depth, the use of traditional leak detection methods was not effective. The Sahara® system identified two large leaks on one of the transmission mains within minutes of being inserted into the pipeline. Not only did these findings allow the PWD to halt a longstanding source of non revenue water, but PWD was able to plan targeted rehabilitation programs for these pipelines to minimize the risk of failures that could impact water supply and traffic flow in a major urban corridor.
Coordinated by PWD staff, the Sahara® system has identified over 47 pipeline leaks for the City of Philadelphia. The proactive leak detection actions taken by the City reinforce the importance of long-term leak detection programs to maximize the revenue and operating life of transmission mains.