Xylem TotalCare Condition Audit, an inspection and recommendation program that helps plant operators find ways to lower maintenance costs by identifying inefficiencies in the operation of water and wastewater equipment, was elected to audit the American Canyon Wastewater Treatment Plant (WWTP) in California.
If you thought reverse osmosis was the one and only choice for potable water reuse, think again. Ozonation followed by biological activated carbon (ozone-BAC) is more suited to inland communities and may be better at removing chemicals of emerging concern (CECs).
A San Jose Water Quality Engineer said, "I wasn’t convinced that PSI’s Monoclor™ chloramine dosing system would solve our problems after several failed attempts to improve residual, but with PSI offering a trial including installation, operation, and troubleshooting for three months, San Jose Water decided to invest the necessary resources to pilot this system.
Installing and operating an ozone oxidation system for wastewater remediation at a gold mine located in a remote region of Alaska is full of challenges.
The Village of Oswego, IL selected WRT’s Z-88® Radium Removal treatment system to remove high concentrations of radium in their public drinking water. Eight city wells are currently being treated by Z-88® Radium Removal treatment systems. All eight treatment facilities are now producing safer drinking water since the first installations in 2005.
Historically, Lyon County Utilities, Nevada, applied 12.5% bulk sodium hypochlorite for disinfection at each of their well sites. Always looking to improve system efficiency, Lyon County staff reexamined on‐site hypochlorite generation to determine if the use of the 0.8% sodium hypochlorite solution could mitigate the challenges associated with dosing high strength sodium hypochlorite.
In Canada and the western United States, long treated water transmission lines are frequently utilized to convey potable water to rural communities. These long transmission lines combined with chlorine for water disinfection can often create the requisite conditions for the formation of undesirable disinfection-byproducts (DBPs). One of the most common DBPs is a family of volatile compounds called Trihalomethanes (THMs) which are regulated in Canada to a level of 100 ppb (part-per-billion) annual average and in the US to a level of 80 ppb.
The Ecomuseum Zoo is home to the most impressive ambassadors of Quebec’s wildlife. All residents of the Ecomuseum Zoo are there for a special reason: orphaned, injured or born under professional human care, each of them could not return to the wild. Hence, they have found a forever home at the zoo.
In 2000, Indiana American Water, a subsidiary of American Water Company, purchased the Warsaw Indiana system which serves a population of over 16,000. Indiana American then completed a Comprehensive Planning Study that included a number of upgrades and improvements to enhance the reliability, safety and water quality of the system.
A potable water plant in Eastern Angelina County, Texas, serves over 2,000 rural customers.
Aqua Engineers is a local Hawaiian company founded almost 40 years ago which delivers operations, engineering, and construction management to the water and wastewater industry throughout Hawaii. Also, as an owner and operator, Aqua Engineers is keenly focused on the return on investment for process equipment decisions, but also on the safety of its operators and surrounding community. Read the full case study to learn why Aqua Engineers chose the Microclor OSHG system provided by UGSI Solutions for both their sites in 2016.
The chromium removal pilot study was conducted for the County of San Bernardino, CA at their CSA 70 Zone J - Well 5 treatment facility. Chromium in the CSA 70 Zone J – Well 5 raw water source exceeds the current Maximum Contaminant Levels (MCL).
Originally built to treat 10 million gallons per day (MGD), the Quail Creek Water Treatment Plant in Washington County, Utah, now has an operational capacity of 60 MGD and a design capacity of 80 MGD.
The 34 MGD Otay Water Treatment Plant in San Diego, California serves a population of approximately 200,000. It is a conventional treatment plant that uses coagulation, flocculation, sedimentation, filtration and disinfection. The plant receives raw water from two different sources — imported water from the Colorado River and runoff water from three local reservoirs.
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).