Lead water service lines that were harvested from older homes, set on shelves that are having water run through them for lead testing at the Marston Water Treatment Plant May 3, 2018.
Six years after Denver Water detected elevated lead in tap water at some homes, state health officials have ordered the injection of a chemical into water supplies to slow lead-pipe corrosion — but utility officials are resisting.
The chemical, orthophosphate, would harm humans and hurt the South Platte River basin, worsening algae blooms and increasing the cost cleaning wastewater, Denver Water contends. Utility officials propose solving the problem with a different chemical to lower the acidity of drinking water, combined with accelerated replacement of old lead plumbing.
This disagreement has escalated into a legal fight, with Denver’s Metro Wastewater Reclamation District, Aurora and the Greenway Foundation battling the Colorado Department of Public Health and Environment in state court — possibly delaying action to deal with the problem.
No amount of lead in water is healthy, according to the U.S. Centers for Disease Control, and even low levels can hurt children — slowing growth, impairing hearing and digestion, shortening attention spans and stunting academic achievement. CDPHE director Larry Wolk, a pediatrician, says removing lead from metro Denver tap water is an immediate top priority.
Denver Water officials have known at least since 2012 about the lead contamination, caused mostly by an estimated 58,000 lead pipelines between water mains and homes that are expensive to replace.
In 2012, tap water tests in homes showed lead levels exceeded a federal health “action level” limit of 15 parts per billion, set in the early 1990s under the Safe Drinking Water Act. CDPHE records show 13 percent of tap water samples taken that year contained lead at levels above the limit as high as 57 ppb.
Subsequent testing in homes showed elevated lead levels ranging from 7 ppb to 13 ppb, with the levels at some homes (fewer than 10 percent) above the 15 ppb limit, CDPHE officials said.
The legal fight erupted after CDPHE officials on March 20 ordered Denver Water to inject orthophosphate. The CDPHE directed Denver Water to conduct a study. This took two years. Upon completion in 2017, CDPHE officials said they reviewed the results over six months — a study that concluded orthophosphate is the most effective method, reducing lead in tap water by 74 percent compared with a 50 percent reduction from using caustic chemicals to lower the acidity of drinking water.
“CDPHE is concerned about any amount of lead in drinking water. We also have a mission to reduce lead where we can,” CDPHE water quality control director Pat Pfaltzgraff said in an interview. “Now that we have this analysis and information, it is our designation that orthophosphate is the best alternative to remove lead from water coming out consumers’ taps.”
Denver Water engineer Ryan Walsh, project manager for the lead project corrosion control study stands behind shelves of harvested lead water service lines taken from older homes at the Marston Water Treatment Plant May 3, 2018.
CDPHE ordered implementation of the orthophosphate approach no later than March 20, 2020, though Pfaltzgraff said Denver Water should start as soon as possible.
“We’re still pressing forward” despite the lawsuit, he said. “We don’t see that the court action will delay our regulatory review.”
Denver Water chief executive Jim Lochhead acknowledged that no levels of lead in tap water are safe yet defended the utility’s preferred method of adjusting the acidity of water as a quick way to reduce pipe corrosion. Lochhead also said teamwork with the CDPHE and EPA would be better than litigation.
“Delivering safe water is our first responsibility. The water Denver Water delivers to our customers’ property is absolutely lead-free, but lead can get into water as it moves through customers’ lead-containing household plumbing and service lines. We are committed to taking the right steps to reduce the risk of lead leaching into water through customers’ plumbing,” Lochhead said in an emailed response to queries.
The problem with orthophosphate, he said, is potential health harm, environmental harm to reservoirs and the South Platte River Basin, and higher wastewater treatment costs.
“In the interest of public safety, we believe further study is needed regarding the potential impacts … before an irreversible change in treatment of our water is implemented,” Lochhead said.
“Once fully studied, Denver Water will implement the best approach, regardless of cost,” he said. “Denver Water would like to work with CDPHE, EPA and other affected stakeholders on a phased approach where we could accelerate enhanced treatment for corrosion control by beginning to implement pH/alkalinity adjustments within the next few months, while taking time to work together to study other viable alternatives that will be potentially less impactful than orthophosphate injection as currently proposed.”
Denver Water for years has held homeowners responsible for replacing the lead pipelines that run from water mains into houses. This typically costs $5,000 to $10,000. But, since 2016, utility crews that discover lead connector pipes while working on water main breaks and replacing water mains have replaced lead pipes at no cost to homeowners, utility officials said this week.
Loans will be available for homeowners who want to replace lead lines, a utility spokesman said this week. And Denver Water provides free lead testing kits for customers who request them.
Nationwide, federal officials say they are ramping up a “war on lead” that may include tougher rules for utilities. Cities currently rely mostly on manipulation of water supply chemistry to try to slow lead pipe corrosion, rather than replacing old infrastructure. Orthophosphate is widely used.
But Denver Water officials this week said injection of orthophosphate would take two years, at an overall cost of more than $6 million, compared with a few months to adjust the acidity of drinking water using a caustic chemical at a cost of less than $2 million.
The lawsuit filed April 19 in Denver District Court argues orthophosphate would raise water provider and sewage treatment costs by “hundreds of millions” for equipment “to treat the phosphorous-laden waters.” It claims increased algae would clog reservoirs and waterways and trigger growth of bacteria that could cause human health harm “from rashes to paralysis to death.”
Metro Wastewater, Greenway and Aurora officials declined to discuss their claims.
Under the Clean Water Act, Metro Wastewater already is obligated, by 2027, to improve its water-cleaning systems to remove phosphorus before water is discharged into the South Platte River.
CDPHE has issued no public health warnings about led in metro Denver tap water since 2012. Denver Water has posted information on a website.
But details of any accelerated replacement of lead plumbing remained unclear.
“Denver Water has never provided us an exact schedule for removing lead service lines,” CDPHE drinking water program manager Ron Falco said.
Overall cost estimates weren’t available.
“Certainly, lead line replacement is a good thing,” Pfaltzgraff said. “We have not ordered that. It is something we would be willing to discuss with Denver Water, in terms of how that would impact the optimal corrosion control treatment designation.”
The U.S. Environmental Protection Agency has backed up the CDPHE’s order, and regional administrator Doug Benevento said he encourages voluntary replacement of lead pipelines and plumbing.
“Working toward the elimination of lead exposure is one of EPA’s top national priorities,” Benevento said in an emailed response to queries. “Overhauling America’s water infrastructure will take several years and millions of dollars but the effort is underway with a significant increase in state revolving loan funding having been authorized in the federal budget.
“We are developing an action plan to work with tribes and state and local partners to address multiple sources of lead exposure here in Colorado and in other Region 8 states,” he wrote.
Federal rules require water providers to replace lead pipelines only if they cannot meet the 15 ppb limit after injecting corrosion-control chemicals. Denver Water currently is considered in compliance because tests have shown tap water in 90 percent of homes contains less lead.
Even when utilities inject anti-corrosion chemicals, old lead connector lines still break down putting low levels of lead into drinking water. But replacing those lines doesn’t address the problem entirely, federal water experts say, because pipelines aren’t the only source of lead in drinking water. The feds say corrosion control chemicals still are necessary even where old connector lines are replaced to address lead that spreads from pipe fittings and faucets.
CDPHE officials this week told the Denver Post they have invited Metro Wastewater, Aurora and the Greenway Foundation to forego their legal fight in favor of working together to protect people and the environment. For months, the CDPHE has encouraged Denver Water to work with them to evaluate water treatment options, but the agency has “not seen anything in writing about moving forward,” state officials said in an email.
“If these parties continue their litigation and we are forced to fight this out in court,” the officials wrote, “we will vigorously defend our decision.”