The continuous struggle to remediate contaminated natural waters, and to reduce the impact of emerging challenges on the supply of safe potable water are key drivers for research and development in the global water industry today.
Managed by the private, non-profit South Jasper Water Supply, Buna, Texas’ water system contains 91 miles of un-looped distribution pipe with historical water losses of up to 30%. A small operations team is responsible for monitoring two water plants, reading 700 meters, repairing leaks, and flushing water to control the water quality. In an effort to spend less time manually flushing hydrants and focus more time on repairing leaks to reduce non-revenue water loss, South Jasper Water Supply purchased and installed two (2) Hydro-Guard® HG-1 Basic/S Flushing Systems.
Chromium is a naturally occurring metal common in the earth’s crust. There are multiple forms of chromium, and one form, called chromium‐3, is actually a required nutrient for human health, in the right amount.
When the City of Midlothian, Texas, was ready to expand their water treatment plant to accommodate a growing population, they carefully considered and investigated their water disinfection options.
Hendersonville Utility District (HUD) serves one of the most populous suburbs of Nashville, Tennessee.
Ensuring the quality and safety of drinking water across the U.S. EPA-monitored 155,000 public water systems has become a national issue.
California’s inland communities have been hit hard by four years of drought, lower groundwater levels, and reduced allocations from the State Water Project.
In April 2013, City Utilities started up three Microclor Model MC‐1500 skid systems, each rated at 1,500 pounds per day of free available chlorine.
Ultrafiltration (UF) membranes have already gained worldwide acceptance in the treatment of drinking water for their removal of chlorine resistant pathogens such as cryptosporidium.
What’s the most sustainable way of dealing with reverse osmosis and nanofiltration membrane concentrate, particularly in water-scarce Florida? Treat it and drink it.
When the Cobb County-Marietta Water Authority (CCMWA) anticipated the need to upgrade the Hugh A. Wyckoff water treatment plant, they turned to granular activated carbon (GAC) technology after vetting several alternatives. The plant, a wholesaler in a two-plant system, processes up to 72 million gallons per day and serves about 350,000 people. Comprising of Wyckoff and the James E. Quarles treatment plant, CCMWA is the second largest water provider in Georgia.
Rapid detection of changes in water quality is critical in water delivery systems, wastewater treatment, and industrial plants for process optimization, environmental regulatory requirements, and consumer health.
The City of Somersworth has a historical background dating back to the early 1900s when it became the first community to start using chlorine to disinfect it’s drinking water.
The removal of contaminants from public drinking water systems in the US is mandated by the Environmental Protection Agency’s (EPA) National Primary Drinking Water Regulations. These are legally enforceable standards that protect public health by limiting the levels of contaminants in drinking water. Similar regulations are managed by agencies worldwide to protect their citizens from drinking water contamination.
There are a plethora of drinking water contaminant removal technologies that public and private water systems use to comply with the EPA’s drinking water regulations. These include reverse osmosis, membrane, nanofiltration, ultrafiltration, chlorine disinfection, UV disinfection and Ozone-based disinfection practices.
The EPA’s list of drinking water contaminants is organized into six types of contaminants and lists each contaminant along with its Maximum Contaminant Level (MCL), some of the potential health effects from long-term exposure above the MCL and the probable source of the drinking water contaminant.
The six types of contaminants are microorganisms, disinfectants, disinfection byproducts, inorganic chemicals, organic chemicals and radionuclides.
Examples of microbiological, organic contaminants are Cryptosporidium and Giardia lamblia. Both of these microorganic pathogens are found in human or animal fecal waste and cause gastrointestinal illness, such as diarrhea and vomiting.
A common disinfectant used in municipal drinking water treatment to disinfect microorganisms is chlorine. The EPA’s primary drinking water regulations require drinking water treatment plants to maintain a maximum disinfectant residual level (MDRL) for chlorine of 4.0 milligrams per liter (mg/L). Some of the detrimental health effects of chlorine above the MCL are eye irritation and stomach discomfort.
Similarly, byproducts from the chlorine-based disinfection methods used by public water systems to remove contaminants can be contaminants in their own right if not removed from the drinking water prior to it being released into the distribution system. Examples of disinfection byproducts include bromate, chlorite and total trihalomethanes (TTHMs). Not removed from drinking water, these disinfection byproducts can increase risk of cancer and cause central nervous system issues.
Chemical contamination of drinking water can be caused by inorganic chemicals such as arsenic, barium lead, mercury and cadmium or organic chemicals such as benzene, dichloroethane and other carbon-derived compounds. These chemicals get into source water through a variety of natural and industrial processes. Arsenic for example is present in source water through the erosion of natural deposits. Many of the chemical contaminants are derived from industrial wastewater such as discharges from petroleum refineries, steel or pulp mills or the corrosion of asbestos cement water mains or galvanized pipes.
Radium and uranium are examples of radionuclides. Radium 226 and Radium 228 must be removed to a level of 5 picocuries/liter (PCI/L) and Uranium to a level of 30 micrograms/liter (30 ug/L).