The District routinely monitors for the presence of drinking water contaminants. Testing results from Quarter 3 of 2016 show that our system exceeds the standard, or maximum, contaminant level (MCL), for TTHM. The standard for TTHM is 0.080 mg/l. It is determined by averaging all the samples collected at each sampling location for the past 12 months. For Quarter 3 of 2016 the level of TTHM averaged 0.082 mg/l for sample site DBP2-01, 0.092 mg/l for sample site DBP2-03, and 0.082 mg/l for sample site DBP2-04. These test results exceed the MCL by 2.5%, 15%, and 2.5% respectively. The fourth test site (DBP2-02) result was below the MCL
What are Total Trihalomethanes (TTHMs)?
Trihalomethanes are a group of volatile organic compounds that are formed when chlorine, added to the water during the treatment process for disinfection, reacts with naturally-occurring matter in the water.
What does this notice mean to customers?
This is not an emergency. If it had been an emergency, you would have been notified within 24 hours.
You do not need to use an alternative water supply. However, if you have health concerns, you may want to talk to your doctor to get more information about how this may affect you. Some people who drink water containing trihalomethanes in excess of the MCL over many years may experience problems with their liver, kidney, or central nervous system, and may have an increased risk of getting cancer.
What is being done?
We continue to work to correct the problem. The District’s staff, engineers and water quality consultant have recommended the District take the following actions to address this issue:
1. TTHMs exist in water as dissolved gasses and can be stripped out of the water by aeration. The District has determined that the low-profile, perforated-stacked-tray type mechanical air stripper is the best choice and is proceeding with acquiring that type stripper for use at its largest production site (Water Well No. 7). The District has contracted with an engineering company and a water quality consultant to design an air stripper unit for Water Well No. 7 to remove TTHM’s before being pumped into the distribution system.
2. The District has negotiated the terms of an enforcement order with the TCEQ that outlines a plan and schedule for returning to compliance with regard to TTHMs. The compliance deadline is 635 days from June 22, 2016, or March 22, 2018.
3. Our customers, however, will continue to receive these notices quarterly until a 4-quarter-average compliance is achieved.
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.
lf you have questions regarding this matter, you may contact Orange County Water Control & lmprovement District No. 1 at 409-769-2669.