We asked Baltimore’s Department of Public Works several questions about its recent finding of cryptosporidium in the Druid Lake reservoir.

If this is only the second time Baltimore sampled and tested for cryptosporidium at Druid Lake and Lake Ashburton, how has the city until now verified that it is not present at concerning levels in these open-air reservoirs?

It hasn’t been legally required to and therefore hasn’t done so, the agency’s answer indicated.

“Each month DPW collects and analyzes samples for cryptosporidium and giardia at the three raw water reservoirs ( Loch Raven and Liberty Reservoirs). There have been no positive test results from any of the samples. In general, when cryptosporidium and/or giardia are detected in raw water, the parasites are removed during water treatment. Regarding finished water (i.e. treated), DPW is now required to test the water at the Druid Lake and Ashburton reservoirs each month for the presence of giardia and cryptosporidium as part of DPW’s recently modified Administrative Order on Consent between the City of Baltimore and the U.S. Environmental Protection Agency (EPA).

“Testing began in late-July 2023, and per the terms of the modified Administrative Order on Consent with the EPA, DPW is required to submit its monthly reports to the EPA and MDE by the fifteenth of each month until the underground tank projects are completed. August 2023 were the first reports submitted per the requirements of the modified Administrative Order on Consent with the EPA.”

Put more simply, DPW does monitor for cryptosporidium at the Loch Raven and Liberty Reservoirs, the system’s “raw water” reservoirs, and removes the parasite during water treatment.

But it has not done so at Druid and Ashburton that receive treated drinking water for temporary storage. The two open-air reservoirs, located in north and northwest Baltimore, are exposed to the elements and to potential contamination by birds or other animals.

In 2006, Baltimore and other jurisdictions with uncovered finished water reservoirs were required by EPA to either enclose the water in tanks or to further treat the water for potential contaminants.

Concerns about cryptosporidium in public water systems arose after a serious outbreak of illness in Milwaukee in 1993.

Federal health officials had stepped up concerns about cryptosporidium in public water systems after a serious outbreak in Milwaukee in 1993.

More than 400,000 people became ill after drinking contaminated water from the city’s supply system. Most recovered on their own, but those with compromised immune systems were sometimes unable to fight off the disease.

It is now believed that as many as 100 people may have died as a result of the incident.

• Ahead of cryptosporidium finding in Druid Lake, city was told repeatedly to end open-air drinking water storage (10/2/23)

In 2010, the EPA issued Baltimore a violation notice for having five open-air reservoirs. Since then, three of them (Towson Finished Water Reservoir, Montebello Filtration Plant II and Guilford Reservoir) have come into compliance.

DPW says it is on track to meet the EPA’s latest deadlines – a November 30 completion date for activating the Ashburton water tanks and December 31 for the Druid tanks.

Long Lab Wait?

Why, if these contaminants put residents – and especially the area’s vulnerable residents – at risk, can’t the city get the results back sooner than five to seven days?

“Five to seven days is the standard laboratory analysis time for these types of contaminants,” DPW replied.

At last week’s news conference, officials themselves pointed out that because of the week-long wait for lab results, the cryptosporidium found in samples collected on September 19 had reached users’ faucets and shower heads long before it was identified and disclosed.

A source with knowledge of the matter told The Brew that a single test for cryptosporidium costs approximately $1,100, not counting the expense to transport it to the lab.

“It’s not a little vial. It has to be, like, a gallon, and it has to be kept on ice,” the source said, noting that the nearest labs capable of conducting the tests are in New Jersey and Pennsylvania.

The Baltimore Banner found closer, quicker, cheaper labs that would do the test, but was also told by DPW it could get the test results no sooner than five to seven days, with no explanation as to why.

EPA reportedly made crypto and giardia testing part of a formal order in May because DPW expressed reluctance about conducting the monitoring.

“We thought it was very important, particularly after that [e. Coli] incident last summer,” Karen Melvin, director of the Enforcement and Compliance Assurance Division for the EPA’s Mid-Atlantic Region was quoted saying.

Tardy Public Notice?

Why didn’t  DPW notify the public right away on September 26 about the cryptosporidium finding?

State officials gave them permission to wait two days, according to DPW, which produced a letter from the Maryland Department of the Environment (MDE) saying so:

“Baltimore City customers, including consecutive systems, must be notified by 9 a.m. Thursday, September 28, that cryptosporidium has been detected in the finished water.”

The letter, from D. Lee Currey, MDE’s director of water and science administration, does not specify particular notification measures to be used, such as the city’s emergency text and robocall system.

DPW says it is working with MDE and other state and local agencies to develop public notification guidelines “to ensure that the most accurate message of water safety is clearly communicated to the public.”

A Level So Low?

“Why were the sample results described as ‘low level’?”

“DPW, Baltimore City Department of Health, MDE, and MDH believe that there is a low health risks resulting from the detected cryptosporidium levels,” DPW said.

At 0.09 oocysts-per-liter, the measurement indicates contamination at a lower level than would likely cause illness in the general public, these officials say.

According to a 1994 modeling exercise cited by the EPA, cryptosporidium exposure during the Milwaukee epidemic ranged from 0.6 to 1.3 oocysts-per-liter.

Richard Luna, interim DPW director, asserted last week that the laboratory also characterized the results as low.

“The sample that was collected and the results back were so low that it was even hard for the laboratory analysts to detect that bacteria, the crypto, in that sample,” he told reporters.

“Per their guidance, they said it would be too difficult to pinpoint the exact source.”

More Information

The city is now awaiting the results of a new sample, collected last Wednesday.

Meanwhile, for those concerned about drinking city water, the CDC’s cryptosporidium page is a good starting point.

It includes information on the life cycle of the parasite, proper techniques for boiling or filtering water and how to recognize symptoms:

• CDC on Cryptosporidium