Groundwater in Southeastern coastal Virginia is depleting due to over-drafting without intentional replenishment. This phenomenon makes the Potomac aquifer susceptible to saltwater intrusion as well as land subsidence, or the gradual settling or sudden sinking of the earth’s surface. The Hampton Roads Sanitation District responded to these issues by using groundwater augmentation as a way to recharge the aquifer, prevent saltwater intrusion, and potentially increase ground elevation.
In an era when everything is done to the extreme – from sports, to home makeovers, to weather predictions – it should come as no surprise that the world of water filtering has joined the crowd. “Extreme” filtering, so to speak, is achieved through the use of high-flow cartridge systems – smaller designs that are able to handle much higher water volumes and pressures at lower costs and with less maintenance.
The city of Buhl, Idaho, obtains all of its drinking water from groundwater sources through multiple wells. Prior to 2009, the city did not treat the groundwater but only added chlorine in the form of bulk 12.5% sodium hypochlorite to provide a disinfectant residual. A combination of factors including: changes in EPA and state DEQ regulatory requirements, growth of the residential population and growth of the industrial food processing customers forced the City to build a new water treatment plant to provide filtration to address the naturally occurring arsenic present in the groundwater.
For Robert Stout, general manager of Mid-Arkansas Utilities (MAU), the primary water provider for a three-county rural area spanning 2,220 square miles, the reason to switch to a dry calcium hypochlorite feeding system was simple, “using chlorine gas was not only dangerous for us, it was a big hassle and time-consuming.”
When Northshore Utility District began searching for a new meter reading solution in 2006, achieving a strong return on investment was a critical factor in its selection process.
The Wellsboro Municipal Authority’s slow sand filtration drinking water plant began experiencing high turbidity and algae events due to elevated levels in their reservoir.
Located in Northern Missouri, the city of Trenton and its more than 6,000 residents pride themselves on self‐sufficiency and pragmatic decision making. During the spring of 2012, the utility embarked on the design and construction of chemical feed system upgrades at the existing water plant that would help the city manage the need for new capacity, better control of trihalomethanes (THM’s) and improve operator safety by removing gaseous chlorine as a disinfectant.
When considering the current state of the water and wastewater industry, water metering is an important part of the conversation.
While there are various less common types of treatment systems used to remove iron and manganese from groundwater (such as ion exchange and ultra-filtration), most treatment systems use some form of oxidation and filtration to oxidize the clear state of iron to a solid form so the solid particles can then be filtered out.
A chemical company which specializes in Clean-In-Place (CIP) systems, contacted Mazzei to discuss the use of ozone as an alternative to peracetic acid sanitation or heat sterilization at their customers’ plants.
Ozone is a powerful oxidizing agent that can be used to destroy the organic compounds that affect the taste and odor of potable water. Environmental concerns have led to increased use of ozone because, unlike chlorine, it does not form hazardous by-products.
Increased gas content often leads to problems with bubble formation in highly viscous fluids. 3M™ Liqui-Cel™ Membrane Contactors can provide a simple, compact, and efficient in-line solution for removing bubbles from viscous liquids before they create problems in a process operation.
Energy costs continue to increase. At the same time, there is increased pressure to reduce utility bills without sacrificing operations or comfort.
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 2013 the Drinking Water Inspectorate for England & Wales announced that water samples collected in England and Wales must be tested in a laboratory that meets specific standards for drinking water sampling and analysis. At the time of the new instruction, the chlorine method employed at the Welsh Water Bretton laboratory was unable to meet these requirements, notably for the prescribed limit of detection. This prompted the laboratory to investigate new analytical options for monitoring residual chlorine.
Pure steam is used in sterilization chambers as a common method to sterilize pharmaceutical products, such as equipment parts, instruments, containers and materials for sterile environments.
In recent years, various perflorinated chemicals (PFCs) have come under increasing scrutiny due to their presence in the environment, in animals, and in human blood samples. There are two major classes of PFCs: perfluoroalkyl sulfonates such as perfluorooctanesulfonic acid (PFOS) and long chain perfluoroalkyl carboxylates such as perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA).
The amount of insoluble matter present in drinking water is an essential quality indicator. Silt, sand, bacteria, spores, and chemical precipitates all contribute to the cloudiness or turbidity of water. Drinking water (DW) which is highly turbid can be unpalatable and unsafe. Consumption of even low concentrations of certain bacteria and other microorganisms can cause serious health effects. Consequently, an accurate and sensitive measurement of turbidity is vital for ensuring that drinking water is free of these contaminants.
NRDC’s new analysis of the most recent EPA data finds that nearly 30 million people in the United States drank water from community water systems that violated the EPA’s Lead and Copper Rule between January 2015 and March 2018.
If your customer base is among the 140 million people who depend upon groundwater for drinking water, irrigation, or agriculture, it is important to know whether you can expect the quality of your source water today to be the same tomorrow. Fortunately, a recent update to the first-of-its-kind assessment of trends in groundwater supply has been announced by the U.S. Geological Survey (USGS) to help you identify emerging problems. The results are detailed in an informative and easy-to-use interactive map.
Water utilities are installing automated meter reading (AMR) and advanced metering infrastructure (AMI) systems more frequently. These systems often help utilities improve customer relations and provide valuable real-time data to improve operations. The ability for various meters to communicate with AMR and AMI technology has become more important as these systems become commonplace.
Following a disaster like the back-to-back hurricanes that hit Texas, Florida, and Puerto Rico in 2017, water systems can become flooded and unable to provide safe drinking water to communities. EPA researchers recognized the need for portable water treatment systems that can quickly and cost-effectively provide safe drinking water to affected communities following a disaster.
Utility managers are continually challenged to run water systems in the most efficient manner. Reducing non-revenue water (NRW) is an important component for system efficiency. In many states, regulators are placing caps on NRW or requiring reductions in the amount of NRW. Accurate and well-planned flow measurement can be used to locate areas of water leakage and reduce NRW.
As technology improves, contaminants can be measured in ever-smaller quantities. Pollutants formerly undetected are now becoming emerging contaminants of concern. Water utility managers must stay abreast of potential new regulations and plan for ways to address these contaminants.
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 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.