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Water Security

child drinking from fountainHealthy, secure communities require clean drinking water, but our water supply is vulnerable. Drinking water is supplied by surface, ground or mixed water sources. Following collection and appropriate treatment of municipal water supplies, drinking water is transmitted to end users via a distribution system that includes pumps, piping and storage networks. These water distribution systems can be damaged if their source water is affected by natural disasters and/or spills of chemicals and oils.

Drinking water distribution systems are also increasingly vulnerable to interruption in service from a terrorist attack, an industrial accident, an extreme weather events, and aging water infrastructure. Once the distribution system has reached homes, schools, and businesses, premise plumbing carries the drinking water to the tap and to appliances, both of which can become contaminated if the drinking water has been severely affected. Similarly, if contaminated water is discharged, the sanitary waste system can be compromised. These vulnerabilities, from source water to waste water systems, present challenges in maintaining good water quality and in ensuring water is available for vital uses. Decontamination of drinking water systems following a contamination event is critical for effectively resuming water system operation and for restoring water for drinking, household, fire protection, hospital use, and industrial purposes. 

EPA seeks to improve the ability of water utilities to prevent, prepare for, respond to, and recover from water contamination incidents that threaten public health and the integrity of our drinking water systems. Regardless of the source of contamination, the ability to reliably and cost effectively decontaminate distribution system pipes and plumbing is critical to rapidly returning the system to service. Making swift and effective decisions will help minimize impacts, the time to return to service, and associated costs.

EPA's Homeland Security Research Program conducts research on water infrastructure resilience and incident response in the following areas:

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