Monday, March 9, 2015

February's Number of Water Main Breaks

Spring is just around the corner, but the frigid February of 2015 was hard on the region. Last week the Potomac Patch reported that the Washington Suburban Sanitary Commission (WSSC), which supplies drinking water to Montgomery and Prince George’s counties (as well as waste water treatment), suffered 426 broken water mains this past February. This was the second worst February on record- in 2007 479 water mains broke. On average, February brings WSSC 132 water main breaks

WSSC pointed to its aging infrastructure and a bitter cold month as the cause of the unusually high number of water main breaks. According to their most recent infrastructure plan WSSC is trying to replace 55 miles of water pipe each year and exercise (turn) 430 valves a year. Though that sounds impressive it is inadequate especially after years of neglect and the size of the system. The WSSC system has almost 64,500 vales in almost 5,600 miles of water pipes. So, the newly increased replacement rate for the water mains is over 100 years and it will take 150 years to exercise all the valves. The valves are needed to shut off water to a section of piping and divert water flow for repairs or when a pipe fails. That is an improvement, but not good enough.

The typical life of a steel pipe is 80 years and replacing less than 1% of water pipe each year and exercising (turning 0.67% of the valves a year is not going to improve the reliability of the system in the foreseeable future. After years of neglect it will take more than 100 years to replace the system. In addition WSSC has more than 350 miles of defective concrete pipe mains serving as the trunk lines in the system. This type of pipe has not been used since the mid 1970’s when they were found to suffer from early failures. WSSC needs to pick up the pace of their pipe replacement program to match the life and age of the system.

DC Water suffers many of the same problems. Their system is older than WSSC and much smaller consisting of 1,350 miles of water pipes, 43,860 valves, and more than 9,510 fire hydrants. The system was mismanaged for years and by 1996 some portions of the water delivery system were 100 years old and the sewage system was almost the same age. The water and sewage rates in place in the Washington Metropolitan Area covered the costs to deliver the water and treat the sewage and replace 0.33% of the system each year, an unrealistic and irresponsible repair and replacement rate. In 2012 that began to change after increasing incidence of failures in the system and DC Water announced that they had tripled the replacement rate to 1% (with of course the increase in water rates) so that in 100 years the system will be replaced. It is likely, given the age of the water system in Washington DC the increase in replacement rate was probably necessary to address what was failing each year. Broken water mains in Washington DC region are so common they are only mentioned in traffic reports.

You hear less about the water main repairs by Fairfax Water, but the cold weather also caused broken water mains in Virginia. Fairfax Water has two Water Treatment Plants the older Griffith Plant drawing from the Occoquan Reservoir and the Corbalis plant drawing from the Potomac River. Water from Fairfax Water is distributed through approximately 3,200 miles of water mains to the county’s homes and businesses. The county replaces about 42 miles of water distribution pipe each year through its system is less than 60% the size of WSSC. Yet, Fairfax Water delivers water to their customers significantly below the national average cost of water, and has the lower retail water rates than either WSSC or DC Water and has a repair and replacement program that responds not only to the water main breaks, but is designed to replace the entire water supply and distribution system ever 75 years within the lifespan of the piping.

The maintenance of the last portion of the water delivery systems are the responsibility of home owners, but it is not the same for all water companies. Fairfax Water’s system ends at the pipe that runs underground from the meter or valve in the center of the street to the main water valve inside the house. It is the responsibility of the homeowner to repair the pipe, street and sidewalk if repairs are necessary. Though the water meters and their settings are owned and maintained by Fairfax Water. The homeowner’s plumbing includes all of the pipes and fixtures on the property, from the meter or valve near the street to the faucets and pipes inside the home. The responsibility for maintaining and repairing the plumbing system falls to the homeowner. DC Water and WSSC system responsibility ends at the property line. WSSC is responsible for maintaining the individual water service (lateral) from the main to the property line. Homeowners are responsible for the piping on their land and in their homes.

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