The Port Washington Water District has been granted an extension allowing for needed time to construct systems to treat 1,4-dioxane in the water supply, and is advising its customers across the Port peninsula, in Flower Hill and in Plandome Manor to reduce irrigation 20 percent to meet the district’s goal of keeping impacted wells offline until treatment is completed.
The district announced Tuesday that it had received a compliance deferral from New York State which will allow the district the needed time to design and construct the treatment systems to remove 1,4-dioxane from the water supply.
The state will only grant the two-year compliance deferral to water providers that have an action plan to construct the advanced oxidation process, or AOP, treatment system, which is required to meet the State’s new maximum contaminant level, or MCL, for 1,4-dioxane, according to water district Chairman David Brackett.
“The district’s goal is to keep the impacted wells offline by requiring the community to reduce irrigation by 20 percent while we work aggressively to get the needed treatment systems up and running,” Brackett said in a statement. “The compliance deferral is a proactive measure reserved for extreme weather or emergency circumstances. However, if we are to meet the water needs of our community during the hotter months—while simultaneously keeping wells offline to construct required treatment—the Port Washington community must reduce irrigation usage by 20 percent.”
On Aug. 26, the state Health Department finalized regulations establishing MCLs for 1,4-dioxane at 1 part per billion. Currently, three of the District’s 12 supply wells have had detections of 1,4-dioxane at or above 1 part per billion.
According to the department, “The MCLs are set well below levels known to cause health effects in animal studies. Therefore, consuming water with PFOA, PFOS or 1,4-dioxane at the level detected does not pose a significant health risk…water continues to be acceptable for all uses.”
“Extensive analysis went into creating a water resource management plan for this summer that manages our limited capacity,” Water Commissioner Mindy Germain said in a statement. “It is important that residents start taking steps now to prepare to reduce irrigation.”
“We are alerting you now to provide plenty of time to advise contractors, consider landscaping choices and consider applying for a smart irrigation controller rebate,” Water Commissioner Peter Meyer added.
Port water district customers are advised to turn back watering times for each zone by four minutes, as it will help save up to 20 percent on overall usage; check for leaks or broken sprinkler heads that wastewater unnecessarily; ensure that automatic rain and soil moisture sensors are working properly; make good landscaping choices, such as integration of native/drought-resistant plants and xeriscaping, as this will lead to lower water usage; and consider installing a smart irrigation controller, since the district has $150 rebates available to residents who make the switch; among other things..
AOP treatment, when coupled with granular activated carbon, is currently the only approved method in Nassau County to rid the water supply of 1,4-dioxane. This treatment combination is also capable of removing perfluorooctanoic acid and perfluorooctanesulfonic acid, should detections of these contaminants ever near the State’s new maximum contaminant levels.
AOP treatment works by mixing an oxidant, in this case hydrogen peroxide, with water and running it through ultraviolet light. This makes a chemical reaction that destroys the 1,4-dioxane molecules. The water then runs through the GAC filters which removes any remaining hydrogen peroxide and impurities prior to entering the public distribution system.
