Contaminants in Drinking Water Supplies
Like calcium, manganese is a naturally-occurring element commonly found in minerals; often in combination with iron. It can be found in soil, water, air, and many of the foods we eat, like seeds and nuts. In the U.S., the manganese levels in the soil can vary greatly by location (see map). And depending on where your drinking water comes from, there’s a good chance it contains trace quantities of manganese, as well. Consumed in small amounts, manganese is an essential nutrient for maintaining a healthy body, just like calcium and iron.
The U.S. Environmental Protection Agency (EPA) has provided guidance for acceptable levels of manganese in drinking water, measured in milligrams per liter (mg/L), for many years. But no regulatory limit has ever been set, and many communities (mostly in rural areas) don’t test their drinking water’s manganese level at all. This is mainly because manganese was viewed for decades as more of a nuisance issue when it came to drinking water, often turning water brown and staining sinks and fixtures with black deposits, but any health impacts were largely unknown.
High Levels of Manganese in Drinking Water Could Have Long-Term Health Consequences
However, ongoing research studies conducted over the last two decades have shown that elevated levels of manganese in drinking water can lead to adverse neurological effects. These effects are most likely to occur in the elderly after a lifetime of exposure to high levels of the element. But some studies have also shown that too much manganese during infancy and childhood may impact learning and behavior in children.
These findings led the EPA to update their water quality regulations by establishing a health advisory level (HAL) for manganese in drinking water supplies. The HAL allows states to issue a Public Notice to communities found to have manganese levels in the water supply that exceed the HAL specifications. When a Public Notice is issued, it’s recommended that consumers use bottled water for drinking, mixing formula for infants, and food preparation until the water supply is properly treated. And unfortunately, boiling water with high concentrations of manganese can actually increase the levels and is not recommended.
Determining Treatment Options: Testing for Manganese
While treating the water supply for manganese and a host of other contaminants is common practice in most large communities, many small communities simply don’t have the resources or equipment necessary to address this concern. Snyder & Associates has years of experience helping communities of all sizes address their water treatment options.
Whether you need to improve an existing water treatment facility or build a new drinking water treatment plant, cost-effective and intelligent solutions begin with a complete water system analysis. The proper treatment method is dependent on several factors including, manganese levels, the presence of other contaminants, and existing treatment methods. Testing will also determine other water parameters such as pH, hardness, iron, sulfur, and oxygen content. All of this information is useful to help determine the proper treatment option or equipment needed for your particular application.
Water Treatment Options to Match Your Community’s Needs
Conventional treatments for managing manganese in drinking water supplies range from phosphate treatment to oxidation and filtration methods. For low concentrations of manganese, a sequestering process that uses phosphate compounds is a simple and inexpensive solution.
When concentration levels are too high to use a phosphate for sequestering, oxidation and filtration is perhaps the best, most common form of manganese treatment. During this process, an oxidizing chemical is pumped into the water supply. This converts soluble manganese into a filterable form. The resulting solid particles can then be filtered out of the water. The type of equipment necessary for this process is widely used at water treatment facilities across the country.
Other technologies that can be used to remove manganese include ion exchange, lime softening, and reverse osmosis. Reverse osmosis involves the use of hydraulic pressure to force water from a concentrated solution to a diluted solution, trapping any contaminants in the concentrate.
All of these methods have particular benefits depending on a community’s needs and resources. Through our analysis of water quality data, we’ll provide our recommendation for the treatment process design that provides the right balance for your community.
Funding & Permitting Assistance for Water Quality Improvements
Snyder & Associates realize the impacts that upgrade and improvement costs can have on communities, both large and small. With years of knowledge and experience with outside funding sources, we’re able to guide you through the necessary steps to acquire critical project funding. Numerous state and federal funding assistance programs are available to help communities with water quality improvement projects. In Iowa, the Drinking Water State Revolving Fund (DWSRF) is just one example. Most states have similar programs. No matter where your community is located, we’ll assist you in navigating all program requirements, along with completing and submitting funding applications.
Likewise, our team is able to coordinate the extensive permitting process typically required for water quality improvement projects. Our experience and relationships with regulatory agencies help to keep projects on schedule and on budget.
Addressing Manganese in Your Community’s Water Supply
There are many different methods available for properly treating manganese in drinking water. But the proper first step is testing. If you are concerned that your community may have elevated manganese levels in the drinking water supply, the Snyder & Associates team is available to put together a plan to meet the needs of your community, as well as current and future water quality regulations.