Drinking Water Violation Reported
Thursday Aug 27th, 2015
BALTIMORE, MD - Due to a violation for one drinking water chemical byproduct, the Baltimore City Department of Public Works will be sending a legally required notice to approximately 1,500 of our customers in the Carney area of Baltimore County. Although this incident was not an emergency, our customers have the right to know what happened and what we are doing to correct the situation.
The Baltimore City Department of Public Works (DPW) routinely monitors dozens of sampling stations across our distribution area for the presence of drinking water contaminants. Quarterly sampling from July 2014 to June 2015 resulted in an average value for haloacetic acids (HAA5) at the Carney sampling location that exceeded the maximum contaminant level by 1 part per billion. The maximum contaminant level for HAA5 is 60 parts per billion; this location indicated a value of 61 parts per billion. The annual averages for all other sampling locations were below the maximum contaminant level, including one in the same hydraulic zone of the water distribution system as the Carney site. Our most recent Carney sample value for HAA5 was below the maximum contaminant level.
What does this mean?
This is not an emergency. If it had been an emergency, customers would have been notified immediately. Haloacetic acids are five compounds which form when disinfectants react with natural organic matter in water. People who drink water containing HAA5 in excess of the maximum contaminant level (MCL) over many years may have an increased risk of getting cancer.
Prior to April 2012, the maximum contaminant level for HAA5 was based upon all samples taken from the entire water distribution system for a running 12-month period. Regulatory changes were enacted at that time requiring utilities to calculate running annual averages for each individual sampling location. In addition, sampling locations were selected based on those with the historically highest levels, and were to include the month with the highest value.
DPW performs monthly sampling for HAA5 three times as often as the mandatory quarterly sampling. If monthly values were used to calculate the annual average, the result would have been 58 parts per billion.
What should customers do?
There is nothing they need to do. They do not need to boil water or take other corrective actions. Should a situation ever arise where the water is not safe to drink, you will be notified immediately.
Certain people may be at an increased risk. Customers with severely compromised immune systems, infants, pregnant women, and the elderly, are at an increased risk, and should receive advice from their health care providers about drinking water.
What is being done?
As you may know, the City has a very old water system which includes large finished-water reservoirs and old water pipes. HAA5 values for water leaving the three water plants are relatively low but the size and age of the distribution system contributes to higher levels in some isolated areas of the water distribution system. DPW has a number of plans in place to help reduce HAA5, including building covered finished water reservoirs, better mixing of water at its storage tanks, replacing older distribution pipes, and implementing a distribution flushing program.
Some of these efforts are already being enacted, while others will require several years to complete. Our most recent Carney sample value for HAA5 was below the maximum contaminant level. For more information, please call 410-396-0150.