With 100 years of service history, Austin Water has seen enormous change in its 540 square miles of service area. Planning for the next 100 years has city and utility planners considering a diversity of sources, system resilience, and sustainability while being mindful of conservation goals. In the city’s newest water treatment plant, WTP4, Austin Water was able to combine those planning elements into a state‐of‐the‐art treatment plant. The plant, which is located on Lake Travis, is capable of treating 50 million gallons a day (MGD) with the ability to expand to 300 MGD.
A single WRT Z-92® Uranium Removal treatment system was selected by the City of Grand Island, NE to remove high concentrations of uranium in three city wells. When the Z-92® Uranium Removal treatment system was installed in 2012, it was the largest uranium treatment facility in the nation. The high uranium in the raw water source is consistently being reduced to levels below the Maximum Contaminant Level (MCL).
When water demand declines, water quality and utility budgets can suffer. When the situation arose in Akron, OH, a smart solution emerged.
Eastern Municipal Water District (EMWD) serves about 142,000 customers in Riverside County, CA. The EMWD service area is one of the largest for any water district in arid southern California. On the drinking water side, EMWD manages two water treatment plants and over 15 reservoirs. With 70% of the district’s water coming from the Metropolitan Water District with chloramine disinfection, EMWD has become reliant on chloramine disinfection to manage long transmission lines and longer detention times.
Most Americans take clean drinking water for granted as a convenience of modern life. The United States has one of the world’s safest drinking water supplies, but new challenges constantly emerge.
Like many cities within the Dallas-Fort Worth metroplex, the City of Coppell experienced water quality challenges at different periods throughout the year. In particular, the City had difficulty maintaining adequate chloramine residuals at the 1.5 MG Southwestern elevated storage tank during the warmer summer months when outdoor watering was restricted to conserve water.
Bathurst is the home of the Bathurst 1000 Race, the largest NASCAR-style “touring car” race in Australia. On race day, tens of thousands of additional visitors tax the capacity of the Bathurst 5 million-gallon-per- day wastewater treatment plant. The diligence and capability of the treatment staff allows the plant to meet the challenge every year.
Nestled in the Finger Lakes region in upstate New York, the town of Owasco is a popular vacation spot. With about 4,000 residents, the town, along with the nearby community of Auburn, relies on Owasco Lake for its drinking water. In 2016, Owasco and Auburn detected algal toxins in their finished water for the first time. With the busy summer tourist season quickly approaching, GHD contacted Calgon Carbon.
Bass Lake Water Company selected WRT’s Z-92® Uranium Removal treatment system to remove high concentrations of uranium from their raw water source. The Z-92® Uranium Removal treatment system is consistently reducing the uranium levels below the Maximum Contaminant Level (MCL) since the 2007 installation.
As PFAS and a host of other pollutants threaten water systems and erode public confidence, the water industry fights back with a comprehensive action plan.
Located at the mouth of the Big Cottonwood Canyon, the Big Cottonwood WTP is one of three water treatment facilities providing treated water to Salt Lake City (SLC), Utah. The utility distributes water through about 1,300 miles of transmission and distribution pipe to over 90,500 connections. Recently, the Big Cottonwood WTP was recognized for delivering 16 years of high quality water and received the Directors Award from the EPA & AWWA Partnership for Safe Water.
A novel biological oxidation filtration treatment process was evaluated for removal of ammonia from a California groundwater source. In addition to ammonia, this groundwater had other contaminants such as iron, manganese, methane, hydrogen sulfide odor, color, high organic carbon, etc. As such, more conventional treatment processes such as breakpoint chlorination were deemed infeasible, and biological treatment was the preferred treatment alternative.
The Mountain Regional Water District is a Special Service District of the county that was established by the Summit County Commission in 2000 to regionalize water service by consolidating several public and private water companies.
As part of a feasibility study for arsenic treatment at an elementary school in California, a pilot study was conducted to test the performance of three different treatment media: (1) greensand and anthracite, (2) standard sand and anthracite, and (3) manganese dioxide.
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).