DC Water Failed to get the Lead Out

Washington DC’s recent internal audit has found that, based on reports submitted to the EPA there is still measurable amounts of lead in Washington DC households' drinking water. From testing it is know that lead is not present in the water before it enters the DC Water distribution system. The lead is coming from either the piping delivering water to the homes (the laterals) or from the household plumbing. The most effective way to minimize exposure to lead is to remove the source of lead, DC Water did not design its regulatory mandated system of controls to identify and remove all sources of lead in the piping and pumps that delivers water throughout the city. Furthermore, the DC Water did not ensure that all sites with lead service lines have been identified, and in  the testing that does take place all wards of the city are not equally represented. In short, DC Water and their plan to replace lead service lines has failed the city residents.

For decades instead of replacing lead pipes urban water companies, not just DC Water have used chemicals to control lead and other chemicals from leaching into the water supply. Many at the American Water Works Association and other trade groups have questioned the wisdom of this strategy, there is always some lead leaching and many of us believe that there is no safe level of lead in drinking water. Yet, having the Washington Aqueduct use chemicals to control lead has been DC Water's  strategy of choice.

In 2001 Washington DC had a lead in water problem much larger than the Flint Michigan “crisis.” The problem in Washington DC was sparked by the Washington Aqueduct’s change from chlorine to chloramine in its disinfection process. As in Flint, the change in water chemistry resulted in a disturbance in the bio-film on the pipes which resulted in lead leaching into the drinking water. It is, however; likely that the lead laterals in Washington DC were leaching lead at a lower level all along.

In 2003, the EPA required DC Water to begin an accelerated lead pipe replacement program. In support of this mandate, the city passed a resolution to fund an accelerated lead pipe replacement program in 2004. This resolution required DC Water to replace all known lead service lines in public space by September 30, 2010, and replace any newly discovered lead service lines within 90 days of discovery. The resolution also required DC Water to encourage customers to replace their private side portion of the lead service lines when the public side is replaced, offering the property owner the same rate as DC Water’s actual cost.

DC Water’s ownership of the distribution system stops at the property line when the homeowner or building owner becomes responsible. DC Water management indicated that the portion of the lead lateral on private property is not DC Water’s responsibility and would not be replaced at DC Water’s expense. Replacing only a section can induce a chemical reaction from the addition of other metals, like copper, in new sections of pipe. So, in 2008 the Board redirected DC Water to replace public lead service lines only with water main replacements. The Board instructed DC Water to use discretionary funds to replace public lead service lines only when a customer requests replacement and agrees to pay for their portion on their private property.

from DC Water

Based on information in DC Water’s service line inventory database, there are a total of 125,574 service lines in Washington DC. There are 19,103 sites with known lead service lines throughout the District. However, the pipe material for 98,969 of 125,574 service lines on customers’ properties were unknown. DC Water can not identify the pipe material for 79% of their customers. At the current rate of replacement, it would take 36 years to replace all 19,103 known sites with lead service lines. If a significant portion of the unknown service lines are made of lead, replacement could take many multiples of that estimate. 

From DC Water

When DC Water customers’ test their drinking water for lead, they did not equally represent all the District Wards. As you can see below, DC Water had fewer samples from Wards 1, 2, 7, and 8 than the other Wards. While the EPA's Lead regulations do not require samples to be evenly distributed throughout a city it is a problem. The material of 79% of the lateral pipes is unknown, so there is a potential risk of lead exposures for those areas not tested for lead. A geographically distributed sample is necessary to be representative of the population of homes with lead service lines in the District. 

DC Water needs a better plan for addressing the lead contamination in the city's drinking water. A few cities, including Madison, Wisconsin, and Lansing, Michigan, have taken steps to remove all of their lead pipes. Such projects can cost tens of millions of dollars for a small city and possibly hundreds of million of dollars for Washington DC. These costs have to paid for by an increase in water bills and also paid by property owners. It was estimated by the American Water Association that there are 6.5 million lead pipes still in service in the United States while the EPA estimates that number at around 10 million. That does not even consider all the homes in America that have copper pipes with lead solder or brass fittings with lead.

EPA regulates lead and copper in drinking water under the Lead and Copper Rule. This rule has undergone various revisions over the years, but requires that: (1) water utilities optimize their treatment system to control corrosion in customers plumbing; (2) determine the tap water levels of lead and copper for customers who have lead service lines or lead-based solder in their plumbing systems; (3) rule out the source water as the source of significant lead levels; (4) if lead levels exceed action levels (0.010 mg/L) the supplier is required to educate their customers about lead and actions they can take to reduce their exposure to lead. If a water utilities’ corrosion control treatment plan continues to fail to reduce lead below lead action level it must begin replacing the lead service lines under its ownership.

In the early 2000’s when the lead action level was lowered, water utilities discovered that just as changes in water chemistry can disturb the protective bio-film, removing lead lines improperly, or taking out only a portion of a line ends up disturbing the coating intended to prevent lead leaching inside old pipes. Replacing only a section can induce a chemical reaction from the addition of other metals, like copper, in new sections of pipe. DC Water needs to take action to address lead exposure now. Water rates will just have to cover the costs to supply a clean and safe water supply to all District residents.