Published: Jun 28, 2013 | 21:09 PM

Properly Maintained Sewers Help Prevent Spills

With more than 933 miles of sewer mains, and 14 sewage pump stations conveying millions of gallons of wastewater per day, Irvine Ranch Water District maintains a goal of zero sewer spills, and takes a proactive approach, rather than a reactive to inspection and maintenance of these facilities.

“Wastewater collections systems can be vulnerable to potential failure, with probable impacts to the environment and to public safety,” said Greg Springman, IRWD Collection Systems Manager.

IRWD’s collection system (sewer system) serves a population of 330,000 including all of the city of Irvine, Newport Coast, and portions of Tustin, Lake Forest, Orange and Costa Mesa. It’s important to point out that IRWD does not maintain storm drains, which is a separate system from sewers.

The District has 17 collection system employees who keep the sewer lines flowing, maintain lift stations, manhole covers and respond to emergencies. There is a fleet of specialized vehicles that help workers do their jobs.

Collection system employees use CCTV trucks to monitor various conditions of eight-inch to 60-inch sewer mains using closed circuit television. Employees are able to inspection these sewer mains by inserting an 80-pound brass mechanical tractor, with an attached adjustable camera which resembling a torpedo on wheels. The tractor and camera is then lowered through a manhole opening where it is controlled by an operator,  tethered on a 1,000-foot cable.

The camera travels through the sewer mains while an employee watches the images on a computer screen inside the CCTV truck. Sewer mains are checks for cracks, roots, and any other type of blockages which may occur. Employees also inspect all new sewer mains prior to being placed into service.

Collection system employees also utilize Hydro/Combination Units to cleaning all sewer mains throughout our community. This specialize piece of equipment can carry approximately 1,500 gallons of water, which is pumped through 600 feet of one-inch hose under high-pressure. The high-pressure hose is inserted into the sewer mains through the manhole opening. The high-pressure stream of water scours the pipe walls as it is propelled through the sewer main removing all accumulated debris. Employees also visually inspect the conditions of the manhole structure as well. Special attention is given to inspecting and cleaning sewer mains within shopping centers because of the potential of grease problems from food service establishments.

The collection system must answer to a host of regulatory agencies, including the Santa Ana and San Diego Regional Water Quality Control boards, the county health department, city code enforcement, and potentially, the Department of Fish and Game.

IRWD’s collection system has won the Collection System of the Year award for medium size systems in 1992, 1995, 1996, 1997, 1998 and 2000 from the Santa Ana River Basin Section of the California Water Environment Association. In 1996 and 2000, IRWD went on to win the Collection System of the Year Award for the entire state of California. The award is based on a site inspection, regulatory compliance and evaluation of preventive maintenance programs, corrective maintenance programs, safety programs and procedures, training programs and emergency procedures.