Safe drinking water is essential to our physical health and the economic health of our communities. However, drinking water is vulnerable to contamination from many potential threats.
The 1996 Safe Drinking Water Act Amendments created a coordinated set of programs and requirements to help water systems make sure they have a safe supply of drinking water. These programs and requirements form a Multiple Barrier Approach that places technical and managerial barriers that help prevent contamination at the source, treatment and tap to provide a safe supply of drinking water for consumers.
The first barrier in a water system’s multiple barrier approach is risk prevention. Risk prevention focuses on the selection and protection of drinking water sources. Systems should be aware of potential contamination caused by agricultural drainage, urban runoff, organic materials and other factors.
When selecting water sources, systems should examine:
- The quality of the raw water (e.g., Does it contain pathogens, chemicals, radionuclides, nitrates, or high turbidity?).
- The risk of contamination (e.g., Will development encroach on the water source?).
- The ability of the supply to meet current and future needs.
The second barrier, risk management, focuses on the protection provided by water treatment and system operations. Public water systems traditionally have relied on treatment to prevent waterborne disease. Treatment continues to play a central role in protecting public health.
- Removes and inactivates contaminants present in source water.
- Leads to improved finished water quality.
No single treatment technology or process can solve every water quality problem, so a water system should consider using a combination of treatment technologies and processes if necessary. Under the third barrier, monitoring and compliance, systems aim to detect and fix problems in the source and/or distribution system as early as possible.
They accomplish this by collecting information about:
- The presence of contaminants.
- The effectiveness of current treatment processes.
- Any deterioration in the quality of source or treated water.
Monitoring the quality of water is very important in the distribution system, as well as throughout the entire water system. Even if water from an extremely clean source is adequately treated, breakdowns in the distribution system can lead to waterborne illnesses. Consumer awareness and participation are key components in the multiple barrier approach. Individual action is considered the forth and last barrier to be considered.
A community water system is required to prepare and provide to their customers, at least annually, Consumer Confidence Reports (annual water quality reports) that discuss:
- The condition of the system’s source water.
- The level of contaminants in the system’s drinking water.
The reports are a way to raise consumer awareness about drinking water, and they can be used as a tool to encourage dialogue between consumers and the water system. Informed and involved consumers can become advocates for improvements in their water system’s operations. Public education and participation can also help consumers become more aware of the true cost and value of water.
From a financial perspective, customers who have a better understanding of their water system, the true cost and value of water and the role they play will be more likely to support the rate increases and bond issues needed to fund multiple barrier approach activities.
To learn more about this approach, check out this page found on EPA’s website.