Haloacetic Acid 5 (HAA5) MCL VIOLATION


(State Water System ID# 3220003)


The Joint Municipal Water and Sewer Commission (JMWSC) has received notice from the SC Department of Health and Environmental Control (DHEC) that DHEC sampling has indicated a violation of the Stage 2 Disinfection Byproducts Rule (DBPR) required by the federal Safe Drinking Water Act.  This is based on sampling that is conducted quarterly by DHEC at JMWSC’s drinking water distribution system (DHEC conducts this quarterly sampling at all other similar drinking water systems across South Carolina).  DHEC’s sample results from July 2015 through June 2016 show that our system exceeds the standard (called “maximum contaminant level” or MCL), for haloacetic acids (HAA5).  HAA5 are five haloacetic compounds that form in water when disinfectants react with natural organic matter in the water.  The MCL for HAA5 is 0.06 milligrams per liter (mg/L).  Compliance with the MCL is determined by averaging all the samples collected at each sampling location over the past 12 months.  The level of HAA5 averaged 0.061 mg/L at two of our system’s locations for July 2015 through June 2016, which represents a .001 mg/L exceedance.  This reported violation indicates a potential long-term health effect as defined by the US Environmental Protection Agency.  *Some people who drink water containing haloacetic acids in excess of the MCL over many years may have an increased risk of getting cancer.* 

The JMWSC purchases and delivers water that has been treated by the City of West Columbia at the City’s Lake Murray Water Treatment Plant.  As our water supplier, the City of West Columbia has responsibility for treatment of your water, and for minimizing Disinfection Byproduct (DBP) formation during the treatment process.  Although the JMWSC does not have full authority over the treatment processes and operations at the City of West Columbia treatment plant, we work closely with DHEC and the City of West Columbia to monitor water quality. 

This is not an emergency.  It is important to note that this reported violation is related to a long-term health advisory.  If there were a water quality concern that required immediate action, we would take steps to notify you quickly (within 24 hours).  If we find that the water entering our system from the City of West Columbia’s treatment plant continues to present compliance challenges, we are prepared to take the steps that are necessary to meet the needs of our customers.  No action is required of you at this time except that we ask that you *please share this information with all the other people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools, and businesses).  You can do this by posting this notice in a public place or distributing copies by hand or mail.*  Also, there is no need for the use of alternative water supplies at this time.  If you have a severely compromised immune system, have an infant, are pregnant, or are elderly, you may be at increased risk and should seek advice from your health care providers regarding drinking water. 

As water professionals we keep a sharp eye on changing state and federal regulations to understand the reality of impacts to our community.  We take seriously our role in providing safe drinking water, understanding and interpreting state and federal drinking water regulations, assessing risk, and keeping you informed while ensuring we do not create undue concern.  We will continue to update you should additional measures become necessary. 

Thank you for your continued support of our critical mission to deliver safe drinking water.  Should you have questions, please do not hesitate to contact us at 803-359-8373 or 

Jay Nicholson

General Manager

For more information about Disinfection Byproducts

Environmental Protection Agency

Centers for Disease Control and Prevention

Public Notification Mailed July 2016




Friday, July 15, 2016 6:05:00 PM