When Eielson Air Force Base, located in the interior of Alaska, found high levels of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in their drinking water, they needed a solution that was effective, cost-efficient, and operable in extreme temperatures. Calgon Carbon’s Model 10 adsorption system, filled with FILTRASORB 400 granular activated carbon (GAC), was determined to be the best option.
With a 2,400 square mile service area and approximately 40,000 customers to serve in southeastern Illinois, EJ Water Cooperative was having difficulties scheduling the nearly 4,000-mile monthly drive to complete a meter reading cycle. The rising cost of their aging system and the need to reduce operating costs prompted the search for a new meter reading system.
When high levels of arsenic were found in the drinking water in the community of Alto Lampa outside of Santiago de Chile, municipal water provider Aguas Adinas faced a predicament. AdEdge Water Technologies was contacted to design a treatment approach. This case study describes how iron oxide adsorption helped Alto Lampa reduce arsenic levels in treated water to non-detectable concentrations.
The emphasis on sustainability in recent years has placed an increased demand on environmentally friendly solutions that adhere to strict regulatory standards. The H2ZeroTM backwash/recycle system from AdEdge Water Technologies conserves water by storing and treating contaminated backwash water from filtration and treatment systems.
Most distribution system water-quality problems can relate back to microorganisms growing as biofilms in the pipes. These biofilms can prompt chlorine residual degradation, corrosion, nitrification, THM formation, red or black water, and taste and odor problems as well as other issues. An effective microbiological control strategy combines the appropriate testing technologies and their use at optimal intervals.
Air release valves play a critical role in maintaining pipeline integrity, but most don’t seal properly at lower pressures without changing to a softer seat, when the system is most at risk. The key to avoiding problems, while achieving optimal performance, is selecting air release valves that work in low- and high-pressure applications. The good news is that there are some advanced valve products on the market that seal over a much wider range.
Located on the Pacific Ring of Fire, the Philippines experience frequent earthquakes, volcanic eruptions, and typhoons that cause catastrophic losses. Manila Water Company, Inc., prepared a Natural Calamity Risk Resiliency and Mitigation Masterplan to ensure that there is a reliable water supply in the event of a natural disaster for the service area covering the East Zone of Metro Manila (the National Capital Region) and Rizal Province.
Many of today’s large urban water treatment plants rely upon sophisticated chlorination processes in order to provide clean, sanitary water to millions of consumers in the US and around the globe. The efficiency and cost-effective operation of chlorination processes in water treatment facilities can be significantly improved with the installation of flow meters that accurately measure the flow of chlorine gas in the treatment process
Turbidity, a measure of the cloudiness or haziness of a fluid, was originally intended as a qualitative measure of the aesthetics of drinking water. It is not a measure of actual particles in the water; it measures how much those particles affect light being transmitted through the water, or how that light reflects off particles in the water. Today’s turbidity designs and methods have been regimented in an attempt to bring quantitative consistency to the measurement for both aesthetic and pathogenic qualities of drinking water.
SUEZ Water Technologies & Solutions designs and manufactures Sievers Total Organic Carbon (TOC) Analyzers that enable near real-time reporting of organic carbon levels for treatment optimization, quality control & regulatory compliance. TOC has a wide range of applicability at a drinking water plant, and therefore any drinking water utility — large or small — can measure TOC in their laboratory or online in their treatment process.
Osmosis is the phenomenon of lower dissolved solids in water passing through a semi-permeable membrane into higher dissolved solids water until a near equilibrium is reached.
Keeping the water in our lakes, rivers, and streams clean requires monitoring of water quality at many points as it gradually makes its way from its source to our oceans. Over the years ever increasing environmental concerns and regulations have heightened the need for increased diligence and tighter restrictions on wastewater quality.
One of the most important measurements in the determination of the health of a body of water is its dissolved oxygen content. The quantity of dissolved oxygen in water is normally expressed in parts per million (ppm) by weight and is due to the solubility of oxygen from the atmosphere around us.
The analysis of Total Organic Carbon (TOC) in seawater can be both challenging and expensive. The concentration of organic carbon in seawater is of considerable interest. The effect this matrix can have on TOC analyzers can lead to rapid consumable turnover, costly maintenance and repairs.
Before water can be used as a safe and reliable source for drinking water, it must be properly treated. Since water is a universal solvent, it comes in contact with several different pathogens, some of which are potentially lethal, and inactivation is accomplished through chemical disinfection and mechanical filtration treatment. This treatment consists of coarse filtration to remove large objects and pre-treatment which includes disinfection using chlorine or ozone
In order to reduce the formation of harmful disinfection byproducts in drinking water, alternative disinfectant use has become increasingly widespread. Monochloramine is a leading alternative disinfectant that offers advantages for municipal water. This tech brief details the removal of monochloramine using activated carbon.
Process design in water treatment is historically confined to proprietary or user-defined spreadsheets on a unit operation basis, with users manually adding results from each unit process upstream into the next operation.
Nutrients in the environment from excess nitrogen and phosphorous can result in negative impacts on water quality. EPA is improving nutrient management by incentivizing the development of low-cost technology solutions, such as nutrient sensors, in collaboration with USGS, USDA, NIST, NOAA, and the U.S. Integrated Ocean Observing System (IOOS).
Tertiary reverse osmosis (RO) wastewater recycling has become a suitable solution to augment water supplies to combat water scarcity across the world. RO desalination in tertiary wastewater processes has proven to provide a cost efficient way to reuse water for both municipalities and industrial organizations.
Municipalities have a new resource in the battle to stretch their water utility capital and maintenance dollars as far as possible. AWWA recently released its first edition of the M77 Condition Assessment of Water Mains. The publication is designed to help water management professionals make better investment decisions by significantly improving their ability to estimate the lifespan of mains.
When designing anything, whether it be a machine, a program, or a process, there are always a few key factors to consider that can determine the validity of the design. Over the past decade, water and wastewater treatment methods have been focused on developing solutions for the water scarcity epidemic with additional emphasis on sustainability. Seawater reverse osmosis (SWRO) plant design requires careful analysis with several criteria to consider in the design of these systems.
To make informed decisions about how to limit exposure to cyanotoxins, utilities need information to select and implement a comprehensive and technically sound management approach. The Water Research Foundation (WRF) has been actively involved in developing effective innovative solutions to help utilities address this challenge and protect public health.
August and September are peak months for harmful blooms of algae in western Lake Erie. This year’s outbreak covered more than 620 square miles by mid-August. These blooms, which can kill fish and pets and threaten public health, are driven mainly by agricultural pollution and increasingly warm waters due to climate change.
In most developed countries, drinking water is regulated to ensure that it meets drinking water quality standards. In the U.S., the Environmental Protection Agency (EPA) administers these standards under the Safe Drinking Water Act (SDWA).
Drinking water considerations can be divided into three core areas of concern:
Drinking Water Sources
Source water access is imperative to human survival. Sources may include groundwater from aquifers, surface water from rivers and streams and seawater through a desalination process. Direct or indirect water reuse is also growing in popularity in communities with limited access to sources of traditional surface or groundwater.
Source water scarcity is a growing concern as populations grow and move to warmer, less aqueous climates; climatic changes take place and industrial and agricultural processes compete with the public’s need for water. The scarcity of water supply and water conservation are major focuses of the American Water Works Association.
Drinking Water Treatment
Drinking Water Treatment involves the removal of pathogens and other contaminants from source water in order to make it safe for humans to consume. Treatment of public drinking water is mandated by the Environmental Protection Agency (EPA) in the U.S. Common examples of contaminants that need to be treated and removed from water before it is considered potable are microorganisms, disinfectants, disinfection byproducts, inorganic chemicals, organic chemicals and radionuclides.
There are a variety of technologies and processes that can be used for contaminant removal and the removal of pathogens to decontaminate or treat water in a drinking water treatment plant before the clean water is pumped into the water distribution system for consumption.
The first stage in treating drinking water is often called pretreatment and involves screens to remove large debris and objects from the water supply. Aeration can also be used in the pretreatment phase. By mixing air and water, unwanted gases and minerals are removed and the water improves in color, taste and odor.
The second stage in the drinking water treatment process involves coagulation and flocculation. A coagulating agent is added to the water which causes suspended particles to stick together into clumps of material called floc. In sedimentation basins, the heavier floc separates from the water supply and sinks to form sludge, allowing the less turbid water to continue through the process.
During the filtration stage, smaller particles not removed by flocculation are removed from the treated water by running the water through a series of filters. Filter media can include sand, granulated carbon or manufactured membranes. Filtration using reverse osmosis membranes is a critical component of removing salt particles where desalination is being used to treat brackish water or seawater into drinking water.
Following filtration, the water is disinfected to kill or disable any microbes or viruses that could make the consumer sick. The most traditional disinfection method for treating drinking water uses chlorine or chloramines. However, new drinking water disinfection methods are constantly coming to market. Two disinfection methods that have been gaining traction use ozone and ultra-violet (UV) light to disinfect the water supply.
Drinking Water Distribution
Drinking water distribution involves the management of flow of the treated water to the consumer. By some estimates, up to 30% of treated water fails to reach the consumer. This water, often called non-revenue water, escapes from the distribution system through leaks in pipelines and joints, and in extreme cases through water main breaks.
A public water authority manages drinking water distribution through a network of pipes, pumps and valves and monitors that flow using flow, level and pressure measurement sensors and equipment.
Water meters and metering systems such as automatic meter reading (AMR) and advanced metering infrastructure (AMI) allows a water utility to assess a consumer’s water use and charge them for the correct amount of water they have consumed.