Water Treatment Changes are Coming: Why and What to Expect
Kittery Water District is committed to providing drinking water that maximizes public health and minimizes potential health risks. Our customers, which include our families, health and safety is our number one priority. Due to concerns expressed by some of our customers, the Board has voted to postpone the transition to allow more time to discuss, improve, and enhance our information process. We have also brought on board a local expert to help us better answer your important future questions and have provided the following, important rational and information relevant to this change and the decision-making process.
What are Chloramines/Monochloramines:
Chloramine is a disinfectant used to treat drinking water. The type of chloramine formed for drinking water treatment is known as “Monochloramine”. It is formed by mixing free chlorine with ammonia at a specific ratio and under specific conditions such as pH >7. Ammonia is added at a relatively low level depending on the amount of free chlorine present. A common dosage for a drinking water with a chlorine level of 2.0 mg/L is 0.44 parts per million (mg/L) of ammonia. Chloramines are safe for humans and most household pet’s consumption except for those animals that absorb water directly in the blood stream such as fish.
Maintaining a level of disinfection in the water distribution system is required to keep water safe. Under the Safe Drinking Water Act, the EPA allows drinking water treatment processes to use free chlorine and chloramine to disinfect drinking water. It is important to note that the target type of chloramine formed for drinking water treatment is known as “Monochloramine”. Research shows that chloramine and free chlorine both have their benefits and drawbacks, however, both disinfection types are tried and true US EPA listed best available technology for use in drinking water. Chloramines use is closely regulated and has been used widely for over 90 years in the U.S. (1926), Canada, and Great Britain and its use has been on the rise in recent years because it reduces disinfection byproducts associated with use of free chlorine.
More than one in five Americans consume drinking water treated with monochloramine. It has been used safely for decades in major cities such as Boston, Dallas, Houston, San Diego, San Francisco, Tampa Bay, Miami, Denver, Philadelphia, Minneapolis among others. In southern Maine, Portland Water District, Maine Water (Biddeford & Saco), Kennebunk, Kennebunkport, and Wells Water District, and York Water District use monochloramine to serve nearly 15% of the population of Maine.
The benefits of chloramine use are extensive and out-weigh the disadvantages;
- Use of monochloramine residual can maintain a better water quality over a longer period of time in the distribution system than free chlorine.
- Water treated with monochloramine has less of a chlorine taste and smell than water with free chlorine.
- Water treated with monochloramine is more stable and lasts longer in the distribution system thereby providing better protection against bacterial regrowth.
- Chloramine forms fewer Disinfection Byproducts compared to chlorine.
- According to the EPA, water utilities switching from chlorine to monochloramine report fewer consumer concerns about the taste and odor of the water.
- The use of monochloramine is often more affordable and requires less new equipment than other alternatives, especially if a water utility is already using chlorine.
- Chloramine technology is easy to install and operate.
- It’s long been understood that interconnected water systems should seek to avoid differences in water quality to optimize the efficiency and effectiveness of the interconnections.
- A few of these efficiencies include; water service redundancy, augmented fire flows, improved service response to major main breaks and other events.
There are however some special circumstances where chloramines must be removed;
- Like chlorine, chloramine must be removed from water used when keeping pets like fish, reptiles, some amphibians, and other aquatic life when it directly enters the blood stream through the gills. Freshwater and saltwater life, like Koi fish, lobster, shrimp, frogs, turtles, snails, clams, and living coral also require its removal. Dogs, cats, ferret, birds, and other animals can safely drink chloraminated water. Consult a local pet dealer or veterinarian if you are unsure about your pet.
- Like chlorine, chloramine must be removed from water used for kidney dialysis. Kidney dialysis patients can safely drink, cook, and bathe in chloramine treated water. The normal digestive process neutralizes chloramine before it enters the bloodstream.
- Like chlorine, chloraminated water may slightly affect beer and bread making. Treatment of process water may need to be additionally adjusted. Carbon filtration remains the best and most economical method, but removal will utilize more carbon and require more contact time. Filters may need to be changed more often. If the remaining small amount of ammonia is desired to be removed, additional treatment is necessary.
- Poor chloramination practices can lead to potential water quality problems; most notably is nitrification. Nitrification results from the bacterial reduction of ammonia to nitrite/nitrate, may decrease disinfectant residual, and cause corrosion. Providing the treatment process is carefully controlled and operational practices are appropriately adjusted and monitored this problem is avoided. Our staff will use accurate and reliable equipment to ensure we provide high-quality drinking water and ensure our system meets all regulatory standards.
Monochloramines and Health:
According to the CDC, Chloramine is recognized as a safe disinfectant and a good alternative to chlorine and has been used as a drinking water disinfectant in places like Philadelphia, San Francisco, Tampa Bay, and Washington D.C. According to the CDC, in 1998, an EPA survey estimated 68 Million Americans were drinking water disinfected with chloramine. Most places have switched to the disinfectant in order to meet EPA standards to reduce disinfection byproducts. The expected 40-80% reduction in DBPs (TTHMs & HAAs) would be a secondary benefit for us.
We take pride in our ability to provide high-quality, safe, drinking water that complies with the Safe Drinking Water Act. EPA and the State of Maine Drinking Water Program requires water utilities to meet strict health standards when using chloramines and other disinfectants. Like with free chlorine, EPA regulates certain disinfection byproduct chemicals formed when chloramines react with natural organic matter. Since the formation of disinfection byproducts (DBPs) is influenced by the disinfectant, we would be required to monitor for additional unregulated DBPs like Nitroso-dimethylamine or NDMA. If it or something new was found, we would make the necessary adjustments to minimize any risk. NDMA was not found in York Water District water so is not expected to be found in KWD water.
The US Environmental Protection Agency (US EPA), Center for Disease Control and Prevention (CDC), and the World Health Organization (WHO) have research and experience that indicates chloramine levels up to 4 mg/L are considered safe and beneficial in drinking water. At this level, no harmful effects are likely to occur. Our normal target dose is expected to be around 2.5 mg/L to maintain at least 1.0 mg/L throughout our system. Please see the Links provided at the end of this document for more information.
According to the EPA, chloraminated water that meets the EPA standard is safe for drinking and other general household activities such as bathing, cooking, laundry, and cleaning. The water can also be used for gardening and for watering lawns with no adverse effects. There are no known interactions between chloramine treated water and any kind of medication.
In 1994 EPA examined inhalation and dermal studies in developing the drinking water health goal (4.0 mg/L) for chloramine but there was not much information available at the time. These studies included both human clinical cases and animal studies. EPA based its health goal on the lowest dose to show any adverse effects then made further adjustments lower to allow for an adequate safety margin. The available studies do not link respiratory, skin, or digestive problems to chloramine at the level the public is exposed to in drinking water. It is possible that some individuals may be sensitive to chloramines, just as some are sensitive to chlorine. There are many different causes of irritations, and the source is difficult to identify and varies with each person. If you believe you experience symptoms connected to chloramine, please immediately consult your physician.
EPA continues to encourage research on the safety of chloramines as a drinking water disinfectant. We will continue to monitor the recommendations of the US EPA and CDC as well as relevant research to make sure operations are based on the best available information.
System Lead and Copper Monitoring:
Changing the chemical properties of any water can affect lead and copper pipes. Lead and Copper levels are strictly regulated in drinking water. The EPA has developed a guidance manual that provides recommendations to systems switching disinfectants in order to minimize increases in the rate of lead and copper corrosion. As recommended, we consistently add a phosphate chemical to form a protective coating on pipes. In addition, for decades now, we have maintained optimal system corrosion control water quality parameters demonstrated by always passing our system’s routine Lead and Copper compliance sampling. The third recommendation applies to optimizing the actual chloramination process. This will also be performed from day one of our transition. To achieve this, we are again collaborating with our interconnected water systems, York Water District and Kennebunk, Kennebunkport, and Wells Water District to learn first-hand the best management practices and take-aways from their successful implementation of chloramination.
We are confident that risks are minimized with this transition with optimization of water quality and the continued use of phosphate corrosion chemical that coats the pipes thereby reducing potential corrosion. However, we will also be required to demonstrate this optimization more regularly through increased State compliance monitoring for Lead and Copper throughout our distribution system. While we continue to closely monitor water quality parameters, we are also required to take 60 samples every 6 months to ensure optimization and continued compliance with the EPA Rule. If we were to fail, immediate public notification would be required.
We have applied and received approval for the change to chloramines from the State of Maine CDC regulatory body known as the Drinking Water Program. They will further inspect and approve our new infrastructure and plans prior to the start of transition.
Use of Gas Ammonia versus Liquid Ammonia for Monochloramine Formation:
Ammonia anhydrous gas, ammonium hydroxide liquid, and ammonium sulfate liquid can all be utilized effectively and efficiently in the formation of Monochloramine residual. While ammonia gas is the least expensive alternative in terms of chemical cost, its use brings with it the most safety challenges. Ammonia gas is used safely and reliably in many industries, but it is a known extremely hazardous substance (EHS) and can be easily released into the air. Its use therefore requires that much higher safety measures be in place and maintained when in use as opposed to the liquid alternatives. These safety measures include but are not limited to; maintaining and updating an extensive Hazardous Materials emergency response plan, maintaining specific monitoring and response equipment, and annual training on the plan with local and regional emergency responders, officials, and fire departments. Gas chlorine must first be dissolved in water before use so a dual feed system must be maintained. Kennebunk, Kennebunkport, and Wells Water District has also determined that using gas ammonia for their system might have led to problems with co-precipitation with minerals and potential breakdown of rubber gaskets over time, although York Water did not find or see such problems.
Both York Water District and Kennebunk, Kennebunkport, and Wells Water District, both of which utilized gas ammonia at one time, have moved to the safer Ammonium Sulfate liquid, produced here in Maine, which provides a much greater measure of safety for staff and residents nearby the filtration plants. KKW also avoids the problems thought to be previously associated with use of gas. The Districts strongly believe that the safety gained offsets the minor increases in budget over use of gas ammonia. For the safety of our staff and customers, ease of handling, economy of scale, consistency of water qualities, and corresponding relatively minor increase in total chemical budget, KWD has also chosen to use ammonium sulfate liquid.
Home Devices that Remove Chloramine:
According to US EPA, boiling water or letting water sit out in an open container at room temperature will not effectively get rid of residual chloramine. Whole house and point of use devices can be used to eliminate the chloramine in household water. These devices are filtration systems with granular activated carbon or charcoal. The National Sanitation Foundation (NSF) independently tests and certifies water treatment systems for chloramine removal. Information on NSF certified drinking water treatment units can be found at the link below.
For more information or if you have additional questions please visit our website (http://kitterywater.org/) or call our office at (207) 439-1128.