Water Quality


Onsite Wastewater Treatment Systems

Onsite wastewater treatment systems, frequently called decentralized systems, refers to any system used to treat and dispose of/recycle wastewater from homes, businesses, industrial facilities, and sometimes entire communities. Septic systems usually serve up to 20 people, oftentimes individual households or small businesses, and include a septic tank and soil absorption field. The frequency of septic systems varies by region, ranging from ten to over fifty percent of homes in some states. Larger, more complex systems use advanced treatment units which treat and discharge to surface waters or the soil. When used properly, onsite systems protect public health and the environment by reducing disease transmission and removing pollution from surface and groundwater. Individual onsite systems are typically regulated by states, tribes and local governments, while large capacity septic systems are regulated by the EPA.

Environmental Health professionals play an important role in managing onsite wastewater treatment systems. Septic system professionals are involved in installing, operating, maintaining, and repairing onsite systems. Professionals with local or state health departments evaluate potential sites for onsite systems, issue permits or licenses for technicians, conduct inspections, and enforce local regulations. Additionally, environmental health professionals partner with industries involved in developing land containing buildings using onsite systems to ensure that these treatment systems continue to discharge clean and usable water.    


Recent Updates

NEHA renews the Decentralized Wastewater Management Memorandum of Understanding Partnership

NEHA is part of a select group of national organizations that signed a Memorandum of Understanding (MOU) with US EPA to improve the quality and quantity of resources and education available to professionals in the wastewater field, state and local regulatory agencies, and those whose work involves building on or buying/selling land with dwellings that will use an onsite system. This past month NEHA participated in a renewal meeting and signing ceremony to continue collaboration between the EPA and other decentralized system partners. NEHA is excited to be a part of improving decentralized wastewater management by aiding consumers and professionals in the field. 


Available Wastewater Resources & Programs

The How Your Septic System Can Impact Nearby Water Sources tool is a newly published set of interactive diagrams which illustrate the relationship between septic systems and drinking water, septic systems and surface water, and ways to improve septic systems and better protect nearby water sources. These resources provide homeowner outreach and education to improve use and maintenance of residential septic systems. An example of the diagrams can be found to the left.   

EPA Septic Wiki

EPA Decentralized MOU Partnership

NEHA Certified Installer of Onsite Wastewater Treatment Systems (CIOWTS) - National credential to certify installers of onsite wastewater treatment systems. The credential covers all forms of installation and is offered at both basic and advanced levels.



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National Groundwater Awareness Week


Groundwater and Environmental Health

"Groundwater is the water found underground in the cracks and spaces in soil, sand and rock. It is stored in and moves slowly through geologic formations of soil, sand and rocks called aquifers." The Groundwater Foundation

According to estimates from the CDC, over 103 million Americans get their drinking water from groundwater sources. For some people that source is tapped by their local water district and is part of a larger water distribution system. For others, it means that the water comes from their private wells directly into their homes. Groundwater is also vital to US food supplies- currently 64% of crops in the United States are irrigated by groundwater.

While groundwater is generally a safe and healthy source of water, its supply is not endless. A number of factors have significant implications on groundwater quantity and quality. Some examples are:

  • Drought
  • Over-plumbing
  • Chemical spills
  • Feedlot run-off
  • Pesticide overuse
  • Leaking sewage systems
  • Pharmaceuticals  

In recent years, drought, especially in the southwest US, has had the biggest impact on groundwater supplies and quality.


Emerging Issues:

Hydraulic Fracturing (Fracking) and Groundwater Supplies

NEHA Resources:

New! Private Well Course

NEHA is proud to announce a new, no-cost, online education opportunity!

The Private Well Class is being provided to NEHA at no-charge by the Illinois State Water Survey and the Illinois Water Resources Center at the University of Illinois. The funding for the Private Well Class program comes from the USEPA through a cooperative agreement with the Rural Community Assistance Partnership. Originally intended for well owners, this course has proven to be a resource for EH professionals for basic well and groundwater understanding. The class consists of 10 courses that can be taken in sequence or individually and are eligible for one (1) CE each from NEHA.

To take the course, visit , http://nehacert.org/.


Other Resources:


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Recreational Water

Healthy Swimming and Recreational Waters

Pools, water parks, and other water-related venues are great sources of fun and exercise, however, with aquatic activities there are risks of waterborne illness and injury. 

Pools and similar facilities can harbor pathogens that make us sick, and sometimes the chemicals intended to inactivate these pathogens can irritate our skin, eyes and lungs.  Fortunately, most of these risks are preventable.  Environmental health professionals can work with aquatic-industry leaders and the public to minimize these risks so we can all enjoy the benefits of recreational water safely.


CDC's Healthy and Safe Swimming Week May 22 - 28, 2017   

According to the US Census, there are over 30 million swimmer visits each year in the United states. CDC's Healthy and Safe Swimming (HSS) week helps create awareness around potential illness and injuries that can occur when enjoying recational waters. The 2017 HSS Week toolkit contains a cover letter, community outreach suggestions, list of resources, sample press release, sample op-ed, sample proclamation, and suggested social media messages that are available and free to use.

Health and Safe Swimming Week Toolkit

Aquatic Healthy and Safety Infographic

NEHA Aquatic health and safety infographic

Download Aquatic Healthy and Safety InfographiC (PDF) 

NEW! CDC Updates the MAHC

The updated MAHC incorporates revisions that were suggested at the bi-annual Council for the Model Aquatic Health Code (CMAHC). The suggestions were categorized, opened for discussion to the CMAHC membership, reviewed again and accepted revisions are added to the MAHC. The CDC website offers a variety of ways to review the changes made as well as PDF versions of the revised code.

The Model Aquatic Health Code

Model Aquatic Health Code (MAHC)

MAHC is a collaborative effort of public health, academia, and industry. By providing a model code based on the latest science, the MAHC strives to keep swimming healthy and protect individuals, families, and communities from preventable waterborne diseases and injuries. The MAHC encourages stakeholder involvement, so please make your swimming pool program aware of the following resources and opportunities to get involved.

Updated Model Code Now Available! 
CDC has released an updated 2016 version of the MAHC. The review process is organized by the Council for the Model Aquatic and will be done bi-annually.

To learn more about the MAHC, view the 2015 AEC presentation:


Meet the CMAHC

The Council for the Model Aquatic Health Code (CMAHC) will serve as a key CDC partner by serving as a national clearinghouse for gathering stakeholder input and advice on needed improvements to the MAHC. Consider joining today.

Questions? Email mahc@cdc.gov

EH20 Recreational Water Virtual ConferenceEH2O Recreational Water Virtual Conference Logo Beach Ball and Water Drop

NEHA is excited to announce its second virtual conference, which will focus on recreational water, happening January 18 and 19, 2017!

The EH2O Conference is designed to enhance the knowledge of environmental health professionals in order to help them better prepare to respond to environmental events of public health concern as well as to bring professionals together in a unique virtual environment to exchange information and discover new solutions to issues in recreational water and public health.

Conference content will include topics such as

  • Model Aquatic Health Code (MAHC);
  • aquatic facilities;
  • research on aquatic facilities;
  • new technologies in recreational water;
  • lessons learned;
  • inspection successes; and
  • stories from the field, among others.



Call for Abstracts

The abstract submission period is now open and will remain open until October 28 at 7pm EST. 


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World Aquatic Health Conference

The WAHC is a scientific conference, attracting a wide range of leading thinkers and professionals involved in the aquatic industry. These include, aquatic facility owners and operators, service providers, consultants, parks & recreation, water parks, manufacturers, academia, associations, builders, community organizations, hotels, government, media, retail, distributors, and health/medical field professionals.

Call to Action: Support Safe and Clean Drinking Water Amendment

Show Your Support for Safe and Clean Water

Every American has the right to safe and clean drinking water. Let's take positive steps so that the tragedy that occurred in Flint, MI will not happen again.

Take action by contacting your elected officials to support a new amendment, led by Michigan Democratic Senators Debbie Stabenow and Gary Peters.  

NEHA urges all of us to contact our U.S. Senators to support this important amendment to assure that all Americans have safe and clean drinking water.


Support Safe and Clean Drinking Water Amendment

Show Your Support for Safe and Clean Water

Every American has the right to safe and clean drinking water. Let's take positive steps so that the tragedy that occurred in Flint, MI will not happen again.

Take action by contacting your elected officials to support a new amendment, led by Michigan Democratic Senators Debbie Stabenow and Gary Peters.  

NEHA urges all of us to contact our U.S. Senators to support this important amendment to assure that all Americans have safe and clean drinking water.


In 2014, Flint, Michigan’s drinking water supply was switched from Lake Huron water treated in Detroit to water from the Flint River treated at the Flint water treatment plant in order to reduce costs.

The new supply was not treated with required corrosion control chemicals and the water caused lead and pathogens to get into the town's water supply from corroding pipes. Researchers from Virginia Tech concluded that lead levels were high enough to be designated as "toxic waste." The Justice Department has also opened an investigation.

In a recent letter to President Barack Obama, the Governor of Michigan, Rick Snyder estimates it would cost $767,419,500 to replace Flint’s water system — a long, costly process that some think is necessary because, without it, residents there couldn’t get clean water.

In early February a proposal by Michigan Democratic Senators Debbie Stabenow and Gary Peters is being offered that would steer $400 million toward the lead-contaminated drinking water of Flint, Michigan ensuring that the process of replacing the pipes and getting Flint’s water supply safely back on line.

Contact Your Senators

Please join us in contacting your senators. You can find them here. 

Thanks for your support - we cannot do this work without you!

Sample Tweet

Support the Safe and Clean Drinking Water Amendment. Find your Senators & download a letter of support here: http://bit.ly/1QIORxe

Sample Facebook/LinkedIn Post

Call to Action! Join NEHA in supporting the Safe and Clean Drinking Water Amendment to ensure that mistakes, like what has taken place in Flint, Michigan, don't happen again. Find your Senators and download a letter of support here: http://bit.ly/1QIORxe

Sample Newsletter Blurb

Voice Your Support for the Safe and Clean Drinking Water Amendment  

Now is the time to contact your Senators to let them know how important it is to monitor the public's drinking water to ensure that mistakes -like those that have taken place in Flint, Michigan- never occur again. The Safe and Clean Drinking Water Amendment does just that, and NEHA stands behind it. NEHA has put together a toolkit for you to take advantage of, where you can find sample social media posts, a downloadable letter of support, as well as a plug-in that makes it easy to find your state's representatives. Please visit http://bit.ly/1QIORxe today, and show your elected officials that you support the Safe and Clean Drinking Water Amendment. 



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