San Francisco Public Utilities Commission has placed an order for a sewer leak detection van to help locate and measure defects that allow infiltration into its wastewater collection system, said Electro Scan, a leading electronics manufacturer.

The commission is a leader is using green technologies to manage its water resources, waste recovery and water use.

It, however, faces the same challenge as other global communities where coastal salt water seeps into its sewers reducing the ability to fully utilise reclaimed wastewater.

Lewis Harrison, manager, Wastewater Enterprise, Collection System Division, SFPUC, said: “Our industry’s long term goal is to achieve 100 per cent reuse of our potable water. But, with global warming, persistent drought, and an already high water table south of Market Street, it is important that we identify and patch unwanted openings into our combined sewer system to minimise salt water intrusion.

“With Electro Scan, we will have a new technology to find leaks and help reduce salt water entering our system so we can increase the beneficial reuse of our reclaimed wastewater.”

Using its patent pending technology, Electro Scan will automatically measure the variation of electrical current that flows through cracks and defects in pipes without relying on closed-circuit television (CCTV) cameras, acoustic sensors, or third party data interpretation, said a statement.

The results will be immediately available in the company’s Critical Sewers cloud application, it said.

Douglas J Lipps, mechanical engineer, Engineering Division, SFPUC, said: “This specialised van identifies defects that are not typically seen by operators using camera based systems.

“More importantly, it provides an estimated rate of infiltration in gallons per minute, for each defect and entire pipe, to help prioritise our repairs.”

Electro Scan’s low voltage technology is also the leading method to certify and accept rehabilitation, relining, and repairs for water and sewer pipes which previously relied on Acoustic or CCTV inspection techniques.

Chuck Hansen, chairman and chief executive officer, Electro Scan, said: “I am delighted to support the resource recovery initiatives at SFPUC and help California achieve its goal for recycled water use. New technologies, like Electro Scan, not only find problems that were previously undetected, but often change the way we prioritise rehabilitation and deliver needed benefits, sooner.”

On each non-rainy day an average of 80 million gallons of wastewater is collected and transported to one of SFPUC’s two treatment plants.When it rains, SFPUC’s wastewater system can collect and treat up to 575 million gallons a day (MGD) through a network of 1,000 miles of pipe.

High salinity or shock loads of sodium chloride adversely affect organic removal at the treatment plant, lowering the efficiency of the treatment process and lowering reusable water levels.

Additionally, high levels of unwanted water in a collection system means higher treatment and transportation costs due to greater pumping and electricity costs, contributing to higher CO2 emissions.
The company’s selection is an integral part of SFPUC’s ongoing commitment to pursue cleaner, greener, and smarter strategies to help manage its business. - TradeArabia News Service