Recently, cyanobacteria and cyanotoxins have become a high profile drinking water quality concern in both the United States and abroad. The combination of weather conditions, agricultural phosphate runoff, and other factors has produced water conditions that have favored the formation of cyanobacteria in surface water supplies.
By 2025 Salt Lake City expects to gain additional 100,000 residents, and the nearby city of Sandy expects to gain another 30,000.
Our nation’s record of progress in advancing public health under the Safe Drinking Water Act is significant.
With people flocking to the trendy Texas metropolis, Austin needed a new treatment plant to sustain its growth — but a “sensitive” touch was required to complete the project while protecting the environment.
The groundwater that a southern Louisiana water utility supplies to local residents has traditionally carried a high amount of organic material and color. In the past, the organics were oxidized and broken down by chlorination, but this practice had gone out of favor due to production of disinfection by-products (DBPs) such as Trihalomethanes (THMs) and Haloacidic Acids (HAAs).
Located 30 minutes North-East of Montreal, Canada, the City of Terrebonne has the last drinking water intake of the many cities along the Rivière des Milles-Iles.
Faced with a tight capital budget, a city in British Columbia required a new design for a water treatment plant capable of a maximum daily water production of 21 MPG during peak demand periods, with an ultimate demand of 29 MGD.
Ultrafiltration (UF) membranes have already gained worldwide acceptance in the treatment of drinking water for their removal of chlorine resistant pathogens such as cryptosporidium.
The City of Palm Coast, FL was experiencing elevated color in the concentrate stream being directed to the lime softening facility to recover as drinking water. In an effort to meet secondary color standards at the lime plant, this water quality issue limited the volume of the concentrate able to be recovered.
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.
In October, the U.S. Environmental Protection Agency (EPA) made a preliminary determination to regulate strontium in the nation's drinking water.
Water is disinfected before it enters the distribution system to ensure that dangerous microbial contaminants are killed.
A study led by the Marshfield Clinic Research Foundation set out to prove the growing evidence 'that our groundwater is fairly heavily contaminated with human pathogenic viruses.'
BI Pure Water worked with University of British Columbia researchers and Lytton First Nation to develop a water disinfection system that addresses the needs of native communities, both cultural values as well as the basic necessity of clean 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).