Parasite found in drinking water could make vulnerable people in Baltimore area sick, DPW says
BALTIMORE -- Low levels of a microscopic parasite were found during routine testing of Druid Lake Reservoir, the Baltimore Department of Public Works said, meaning the drinking water could sicken some vulnerable populations in parts of Baltimore, Baltimore County and Howard County.
The parasite Cryptosporidium could potentially cause gastrointestinal problems in those who are immunocompromised, elderly, or children, officials said. Those populations are advised to take precautions like boiling their drinking water.
"Please rest assured that our drinking water remains safe for the general population. This is not related, or in any way comparable, to previous water-related issues," the agency said in a statement.
West Baltimore resident Clarence Young said he's concerned by the situation.
"We're just getting off a pandemic, and now you have a situation with the water. One would be a little afraid or paranoid about that," Young said.
Dr. Tamar Green from the Baltimore City Health Department said that the risk has been determined to be low based on data from DPW.
Since the samples take a week to return results, water from the reservoir has been released.
What area is impacted?
Residents can use this Interactive Map to determine if they live in an impacted area.
The impacted area includes much of and west and north Baltimore City, as well as the Towson, Parkville and Cockeysville areas. In Howard County, parts of Elkridge may be affected.
The area within the red line of this image from the interactive map is impacted:
DPW officials said samples were collected on September 19, and the results of the test came back on Tuesday, September 26.
The agency said it does water testing monthly and August testing showed no signs of Cryptosporidium.
What is the parasite?
The DPW said Cryptosporidium is a microscopic parasite that is commonly found in lakes and rivers, and it is found in every region of the U.S. and around the world.
The parasite can cause cryptosporidiosis which, according to the CDC, can cause watery diarrhea. The agency said other symptoms of the illness include:
- Watery diarrhea
- Stomach cramps or pain
- Dehydration
- Nausea
- Vomiting
- Fever
- Weight loss
The CDC said the parasite was the leading cause of waterborne disease outbreaks linked to recreational water in the United States.
Am I safe?
The DPW said the levels of Cryptosporidium detected "indicate a low risk for the general population," meaning the water is safe to drink for most people.
Vulnerable populations should consider taking precautions. Those populations include:
- Those with inherited diseases that affect the immune system
- Those with HIV/AIDS
- Cancer and transplant patients who are taking certain immunosuppressive drugs
- Elderly people
- Children
What should I do?
Those who may be part of a vulnerable or sensitive population are advised to:
- Drink bottled water
- Boil water for one minute before consuming
- Filter tap water using a filter labeled to ANSI/NSF 53 or 58 standards, or a filter designed to remove objects 1 micron or larger. These may be labeled "absolute 1 micron." (i.e., not Brita-type filters)
What happens next?
Cryptosporidium is extremely chlorine tolerant so secondary treatment is unlikely to reduce its levels, the DPW said.
The agency said it will conduct more frequent sampling for the parasite at Baltimore's finished water reservoirs until it is not detected, and it will notify the public of the results.
This is a developing story and will be updated.
