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When the area’s boil-water alert was lifted last Saturday, residents brewed coffee, made ice, and kicked back to enjoy another day of the Skins’ self-destruction. The only lasting effect of the water panic seemed a collective ability to pronounce “cryptosporidium” and “turbidity.” But public health sources remain distrustful of the water treated by the Army Corps of Engineers. They also suggest that the Corps delayed public notification; that Dalecarlia treatment plant workers were scapegoated; that the negative cryptosporidium test results are misleading; and that the boil alert was prematurely lifted. For the obvious political reasons, these sources chose not to be identified.
One month ago, Washington City Paper detailed the systemic problems of the D.C. water supply (“Muddying the Waters,” The District Line, 11/12), disclosing that the water supply’s high bacteria levels violated Environmental Protection Agency (EPA) regulations and that the filtration systems at the Corps’ two treatment plants were hopelessly antiquated. Public health officials openly criticized the District’s water works then; now the HO wizards are whispering that, unless the Corps’ water infrastructure is revamped, boil-water alerts will become as common as traffic backups on the Wilson Bridge.
The fact that the testers failed to find cryptosporidium is not as reassuring as one might hope. According to a study by Dr. Jennifer Clancy, director of water quality at the Erie County (N.Y.) Water Authority, the best of labs can accurately detect the protozoa only 5 to 10 percent of the time even when samples are amply tainted.
Health officials further contend that the samples tested last week were not representative of the water supply. The highest levels of water turbidity occurred at 2 a.m. Tuesday, Dec. 7, but almost two days went by before testing for cryptosporidium and other pathogens began. When the tests were performed, the plant’s water was running clear, but by then the contaminants could have piggybacked on the excess sediment passing through Dalecarlia and entered District and Northern Virginia homes and businesses. Yet EPA and the Corps confined their three days of testing primarily to Dalecarlia. Additional samples were collected from only two other locations: an Arlington pumping station and a Bryant Street location in D.C. Such skimpy testing could have overlooked tainted water that may have entered the system during the “spike” (or highest level of turbidity), critics say. But Jim Elder, chief of EPA’s Ground Water and Drinking Water Division, says he’s confident that the testing sites were appropriate.
Yet no one doubts that some pathogens entered the Washington area’s water system during the high-turbidity period. Media reports stating that turbidity levels did not violate EPA regulations were in error, sources say. The EPA baseline for normal turbidity levels is .5 NTUs (a turbidity unit); any plant that operates above 5 NTUs for four hours is in violation of EPA regulations. On Tuesday, Dec. 7, the Dalecarlia plant recorded levels that maxed at 9 NTUs, almost twice the legal limit and 18 times normal operating parameters. EPA sources say this means that high levels of bacteria and parasites probably scurried through.
While heavy rains have been labeled the turbidity culprit, the Fairfax County Water Authority and Washington Suburban Sanitation Commission, both of which gather, treat, and distribute Potomac River water, kept their turbidity levels at or well below .5 NTUs.
Given that contaminants were present in the distribution systems of D.C. and much of Northern Virginia, local water authorities should have conducted widespread flushing to cleanse the systems. Arlington and Falls Church purged some of their pipes, but Washington’s Department of Public Works (DPW), whose reticence to flush its pipes was previously expounded here, did not flush at all. (Director of Public Works Betty Hager Francis defended DPW’s flushing policy in a letter to the editor of City Paper, published Dec. 3.) According to EPA, DPW told the federal agency that it will not maintain a flushing program during the winter months out of concern that the water might freeze on city streets and cause traffic tie-ups.
Some public health and EPA officials now say that the boil alert shouldn’t have been lifted until more water was tested and a greater effort was taken to flush the system. Many admitted that they are not drinking tap water themselves.
News accounts have laid blame for the water crisis on Mutt and Jeff, those nameless Corps workers who didn’t add the aluminum sulfite (alum) coagulant to reduce turbidity levels in a timely manner. The implication of this finger-pointing is that if the right blue-collar heads are smacked, our water will be safe. But that’s wrong. Turbidity levels began exceeding EPA regulations on Sunday, Dec. 5, a fact that EPA only learned Dec. 14. Four days of constant turbidity violations implicate many shifts of workers, as well as the highest levels of Corps management, EPA sources say.
One reason the Corps can’t keep up with EPA standards is its antiquated, and apparently dangerous, water-treatment infrastructure. Months before the turbidity problem, obsolete equipment and outdated monitoring practices allowed high levels of bacteria to find their way into local taps, with fecal contamination discovered throughout the city, including at the White House (which has its own filtration system). In fact, according to EPA sources, at one point last month, a notice was posted at the Dalecarlia plant telling workers not to drink from the plant’s water fountains. EPA sources add that human error is inevitable, but a modern water plant with redundant safeguards would prevent mistakes from developing into public health crises.
Since September, the Corps has been under an EPA emergency order—which bound it to increase testing and share the results with the agency. Federal officials, who are increasingly losing faith in the Corps’ ability or willingness to report violations, suspect there may be a long-standing torbidity problem.
After issuing the emergency order, the EPA criticized the Corps’ filter-cleansing process, which occurs every 92 hours. During this cycle, the flow is reversed and water is pumped backward through the filters to free any gunk that has accumulated there. In most modern treatment plants, that cleansing water (known as “backwash”) is routed to sewage drains, or carefully recycled. At the Corps plants, backwash is dumped back into the reservoir and merely refiltered—an oversight that can actually serve to concentrate contaminants. Most plants also “filter to waste,” or discard the first batch of water that comes through the newly cleaned filters—the Corps plants do not.
Two weeks before the water scare, EPA national officials composed an order that instructed the Corps (via EPA Region III) to conduct a comprehensive examination of the filtration process—and to estimate the cost of needed upgrade and repairs—including problems with the backwash cycle. EPA also wanted an evaluation of filter run-times, composition, and maintenance schedules, and the capacity of the settling basins. EPA suspects that eels inhabiting the system’sreservoirs may be to blame for some of the contamination. Sickened by chlorine, the eels burrow into the filters, where they die and rot, leaving holes in the filtration medium of sand, gravel, and anthrafilt (a layer of hard coal). Better screens can repel the eels, but one EPA engineer estimated that the repairs needed to the two Corps treatment plants would cost at least $50 million. (Unfortunately, on Tuesday, Dec. 14, Region III officials informed headquarters they had not yet passed the maintenance prescription on to the Corps.)
Kim Fox, an EPA engineer who dealt with the recent drinking-water crisis in Milwaukee, says that maintaining a modern infrastructure is the best policy, since chlorine doesn’t kill protozoa like cryptosporidium. The best way to battle the parasite, he says, is to prevent it from entering the water system in the first place.
EPA officials are currently investigating why the public was not alerted to amplified turbidity until 18 hours after the Tuesday spike and four days after turbidity problems were first indicated. The Corps followed the tactic employed by DPW during the September water crisis, notifying the public as late as EPA regulations would allow. But ongoing water troubles have raised questions about EPA’s ability to enforce Safe Drinking Water Act regulations over another federal agency. Federal regulations permit the Corps to negotiate with EPA whenever it violates the water regs, unlike other jurisdictions that must automatically comply or face EPA fines.
EPA officials who are critical of DPW’s water standards also worry that the city agency will fail to reform its ways now that the Corps is being blamed for the latest fluid fiasco.
Though Elder denies that political pressures steered any EPA decisions, other EPA officials say that both the Corps and the mayor’s office wanted the problem dismissed quickly, which resulted in a premature lifting of the boil alert.
Acknowledging its faults, the Corps has announced that a contractor will evaluate both treatment plants for upgrades and repairs. One such modification, says Elder, might involve replacing the anthrafilt now used in the Corps filters with granular activated carbon (GAC). GAC is better at precipitating particulate matter and has the added advantage of lowering chloroform and other trihalomethanes (THM), carcinogenic byproducts of chlorine. The Potomac River is rich in organic material, so the Corps hits city water with doses of chlorine. Consequently, area water frequently exceeds THM levels set by EPA.
Switching to GAC and making other modifications to the Corps plants is a multiyear, multimillion-dollar process, says Elder. In the meantime, he adds, the Corps has promised to better supervise its operations and its data, and EPA is committed to making sure that they do just that.