CASE STUDIES AND WHITE PAPERS
Comparative disinfection studies using 3 oxidizing biocides and 3 commonly used non-oxidizing biocides against Legionella pneumophilia.
Solving A Taste and Odor Problem Step By Step (Article)
The City of Alliance Ohio’s water system has experienced annual Taste and Odor (T&O) events since the mid 1950’s, when the first of two reservoirs, Deer Creek Reservoir, was placed into service. Nutrient contaminants, in particular phosphorous, in the watershed accumulate in the reservoirs causing algal blooms. By Terry Keep of TrojanUV, Said Abou Abdallah of Arcadis, and Dr. Dean Reynolds, Department of Water Treatment City of Alliance, Ohio
Low Pressure, High Output 800‐Watt Amalgam System Performing Efficiently
The Trail Lakes Hatchery is owned by the State of Alaska and is managed under contract by the Cook Inlet Aquaculture Association (CIAA) on behalf of the Alaska Department of Fish and Game. CIAA was established in 1976 to provide the Cook Inlet drainage with an organized and reliable salmon stock. The Trail Lakes facility is permitted to introduce sockeye and coho salmon at several sites throughout the Cook Inlet watershed.
Municipality Removes Biofilm, Improves Water Quality, Lowers Dosage With MIOX
Looking to reduce potential disinfection byproducts issues that new and difficult regulations were requiring, a Tennessee municipality began investigating alternative water treatment disinfection methods in an effort to reduce the potential liability (RMP) involved with using and storing gas chlorine. Within months of switching to a mix of oxidants (MOS), a difference was noted in the systems residual, residual was no longer dead spotting in low flow areas, and much higher residual was noted in areas that had been difficult to maintain At the end of the first year of operation the municipality had also documented a reduction in their disinfection byproducts formations, specifically both TTHMs and HAAs, which were both reduced by 50% in direct comparison with the quarterly results from the previous year.
Guaynabo WTP In Puerto Rico Saves Thousands With UV 254 Monitoring Package
Dealing with fluctuating water sources is not an easy task for plant operators. Seasonal variation, heavy rain fall or accidental contamination events change the raw water quality, requiring immediate attention. This is a familiar scenario for Facility Manager, Nancy Ma. Cáceres Acosta at the Los Filtros Water Treatment Plant in Puerto Rico. She has been producing highquality water for 256,000 local residents, receiving surface water from the Guaynabo and Bayamon River
Hydro-Guard® Improves Water Quality And Saves Man-Hours For Central Texas Vacation Community
The user population of the Horseshoe Bay Water Distribution System does not reach its peak until summer and the resultant levels of peak and low usage vary widely.
The Nationwide Impact Of California’s Hexavalent Chromium Regulations
California recently became the first U.S. state to regulate hexavalent chromium in drinking water. Will others follow suit?
Ozone Disinfection System Provides Second Stage Treatment For Water Treatment Plant
Tampa Bay Water’s state-of-the-art surface water treatment plant has provided high-quality drinking water to the Tampa Bay region.
Targeted Algal Management Plan To Address Taste And Odor Problem
Lake John Hay is located six miles northwest of Salem, Indiana and is used for drinking water and tournament and recreational fishing. With an average depth of 14-15 feet, it is ideal for algae and plant growth. The persistent, recurring algae blooms was causing taste and odor problems, which led to frequent complaints.
Ozone Disinfection System Lowers Turbidity, Boosts Filter Run Times, And Eliminates Taste And Odor Issues
By 2025 Salt Lake City expects to gain additional 100,000 residents, and the nearby city of Sandy expects to gain another 30,000.
Microcystin Concentrations Following Treatments Of Harmful Algal Blooms
Microcystin producing cyanobacteria blooms were sampled and tested from an Illinois reservoir, an Ohio reservoir and a Michigan lake.
4-Log Virus Inactivation - Abington, Pennsylvania (Case Study)
The Hall Road Well Station — located in Abington, Pennsylvania — is designed to extract and treat 1.5 million gallons per day (MGD) of water from the Piedmont and Blue Ridge crystalline-rock aquifers. It is part of a network of groundwater extraction wells owned and operated by Aqua-America Pennsylvania (Aqua PA). Aqua PA determined that UV technology was the best approach for meeting the Pennsylvania Department of Environmental Protection regulations for 4-log virus treatment of groundwater. This case study will show you why they chose the TrojanUVSwift™SC.
Multi-Barrier Disinfection Strategy - New York City (Case Study)
New York City is home to more than 8 million people, making it the most populous city in the United States. The majority of New York's drinking water is supplied by the Catskill/Delaware watershed, located approximately 100 miles outside the city. Historically, NYC has not filtered the water from this system, nor did they require any additional barriers to microbial contaminants due to the pristine nature of the watershed.
Transporting pure salt - the raw material needed to generate sodium hypochlorite onsite – is more cost effective, stable, and safer, than transporting and storing bulk sodium hypochlorite, or gaseous/liquid chlorine cylinders from local chemical suppliers. The conversion to on-site hypochlorite generation can be achieved by adhering to these design guidelines.
CONTAMINANT REMOVAL PRODUCTSMore Products
DRINKING WATER CONTAMINANT REMOVAL PODCASTSMore Podcasts
CONTAMINANT REMOVAL APPLICATION NOTES
CONTAMINANT REMOVAL VIDEOSMore Videos
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).