Monday, August 29, 2016
You are Responsible for Your Water Quality
Although the majority of the United States' population gets its drinking water from pubic systems, approximately 43 million Americans or about 15% currently rely on a private water supply system (i.e. wells, springs, and cisterns) for drinking water. Most of these private water systems are private wells. The concentration of private wells is not evenly distributed throughout the country. The Census Bureau stop collecting information specific to private well use in 1990, and now most statistics related to private water supply systems are outdated. However, in 1992 the Commonwealth of Virginia began regulating the construction of private wells and is able to report that over 20% of the state’s population is dependent of private drinking water wells. The majority of households in the most rural 60 of the state’s 95 counties rely on private wells. During 2013-2014 14,791 permits for private wells were issued by the Virginia Department of Health.
The quality and safety of private or domestic wells, are not regulated under Federal or, in most cases, state law. In Virginia only construction and the absence of bacteria at well completion are required. The U.S. Environmental Protection Agency Safe Drinking Water Act (SDWA) cannot and should not regulate individual households, they are challenged enough with the regulation and monitoring of public water supplies. As a result, individual homeowners are solely responsible for maintaining their domestic well systems and for any routine water-quality monitoring that may take place. However, private well owners often lack a basic understanding of groundwater and wells and the mechanical components in private water systems and are often unaware of common issues with wells, and lack access to objective information and a framework for understanding problems and decision making.
As part of the National Water-Quality Assessment Program of the U.S. Geological Survey (USGS), water samples were collected during 1991–2004 from private water wells used for household drinking water from 1,389 wells all over the country. The USGS analyzed the drinking water samples physical properties and the concentrations of trace elements, nutrients, radon, and organic compounds (pesticides and volatile organic compounds); fecal indicator bacteria and radionuclides. The USGS found that 23% of wells the U.S. Environmental Protection Agency (EPA) Safe Drinking Water Act’s (SDWA’s) MCL (maximum contaminant level) for chemical contaminants (e.g. nitrate, fluoride, pesticides). In addition, 34% of samples tested positive for total coliforms and 8% tested positive for E. coli. Although the SDWA does not regulate domestic wells, its approach to evaluating the suitability of drinking water for public supplies is how water quality is typically measured.
Because private drinking water wells serve more than a fifth of its population Virginia has taken steps to assist private well owners monitor, understand and maintain their wells. The Virginia Household Water Quality Program (VAHWQP) was created by the Virginia Cooperative Extension to provide affordable water testing and education about private water wells to residents of the Commonwealth. Volunteers and Extension Agents hold drinking water clinics and other outreach programs. During 2012, the VAHWQP Drinking Water Clinics were held in 33 counties across the state and had a total of 831 participating households sample their water. Samples were analyzed for: iron, manganese, nitrate, lead, arsenic, fluoride, sulfate, pH, total dissolved solids, hardness, sodium, copper, total coliform bacteria and E. Coli bacteria. These are mostly the naturally occurring contaminants and common sources of contamination: a poorly sealed well or a nearby leaking septic system, or indications of plumbing system corrosion. Though this is not an exhaustive list of potential contaminants, these are the most common contaminants that effect drinking water wells.
In 2012 Drinking Water Clinics were held in the following 33 counties: Albemarle, Brunswick, Charlotte, Clarke, Essex, Fairfax, Fauquier, Fluvanna, Frederick, Greene, Halifax, King George, Lancaster, Loudon, Louisa, Lunenburg, Madison, Mecklenburg, Montgomery, Nelson, Northumberland, Orange, Page, Prince William (yeah us!), Rappahannock, Richmond County, Russell, Shenandoah, Spotsylvania, Stafford, Tazewell, Warren and Westmoreland. In the years since 2012 the VAHWQP has continued to hold drinking water clinics throughout the state and has amassed the largest database of well information in the nation,
In 2012 42% (349) of samples tested positive for total coliforms, and approximately 7% (55) samples tested positive for E. coli. The percent of homes with coliform bacteria present was significantly higher than the USGS national findings, but the percent of homes with fecal bacteria present was slightly lower. Coliform bacteria are not a health threat itself, it is used to indicate other bacteria that may be present and identify that a well is not properly maintained or sealed from surface bacteria. The federal standard for coliform bacteria is zero, but the federal standard allows that up to 5% of samples can test positive for coliform during a month. Coliform bacteria presence can be seasonal. Fecal coliform and E. coli are bacteria whose presence indicates that the water is contaminated with human or animal wastes. Disease-causing microbes (pathogens) in these wastes can cause diarrhea, cramps, nausea, headaches, or other symptoms. These pathogens may pose a special health risk for infants, young children, and those with compromised immune systems.
Nitrate-N concentrations were generally low compared to previous studies (Bauder et al., 1993; Gosselin et al., 1997), with only three samples exceeding the EPA MCL of 10 mg/L. Nitrate can contaminate well water from fertilizer use; leaking from septic tanks, sewage and erosion of natural deposits. The MCL for nitrate is 10 mg/L. Infants below the age of six months who drink water containing nitrate in excess of the MCL could become seriously ill from blue-baby syndrome and, if untreated, may die. Closer attention to the potential for nutrient contamination in our waterways could be the reason that elevated levels of nitrate were below earlier studies.
More than half of participating households in the 2012 study did not have water treatment of any kind. For those systems that did include a treatment device, sediment filters and water softeners were the most common. These devices treat aesthetic contaminants and are aggressively sold by home stores and water treatment companies that offer free testing for water hardness. Filters and water softening systems cannot reduce microbial contamination. Only 4.2% of the households sampled in 2012 used treatment device designed to kill microbial organisms (chlorination and UV systems).
If a system is properly constructed and maintained then high levels of contaminants should not be present in the system, but over 42% of wells tested found coliform bacteria present in the sample. Given the prevalence of coliform bacterial, there appears to be a lack of proper maintenance and over time a deterioration in the elements of proper well construction that allows the entry of surface bacteria to enter a well. This is believed to be a result of system neglect and the absence of regular water testing and renders these households vulnerable to exposure to waterborne disease outbreaks. There is a demonstrated need for the VAHWQP affordable water testing clinics, technical assistance and educational materials for private water wells owners in the Commonwealth, but it is also necessary for well owners to be responsible and informed.