Facility and infrastructural security are an important component of any emergency response plan. Whether the outcome can result in vandalism, theft, terrorism, or a threat to staff or community safety, suspicious activity should always be taken seriously. When the city of Woodland Hills was alerted of trespassing at their water storage tank, the utility promptly issued a boil order until they could confirm that their water was safe to drink. These actions prevented any potential harm due to contamination leaving community members safe and reassured that their utility was taking an active role in water security. Evaluating risk to malevolent acts will allow your system to initiate or upgrade preventive measures and develop an appropriate response plan to protect staff and the community. To prevent malevolent acts, start by taking an assessment of your facility’s vulnerabilities . Consider entry points, security code accessibility, chemical tanks, storage tanks, vehicles, utility equipment, hazardous chemicals, and infrastructure within the distribution or collection system. Infrastructure essential to operations and limited in redundancy or identified to be at greater risk to malevolent acts may require more meticulous security measures. To assess physical security threats, check out the Security Vulnerability Self-Assessment Guide for Small Drinking water Systems . The goal in a vulnerability assessment is to determine where prevention measures can be implemented and develop a response plan to suspicious activity. According to the Minnesota Department of Health, many facilities increase security by locking entry points, using external lighting, posting warning signs, requesting law enforcement patrol, fencing in critical infrastructure, or installing motion sensors, alarm systems, and video cameras. Once all preventive measures have been taken, develop a response protocol for each potential threat. The Association of State Drinking Water Administrators has developed response guidelines for security violations. In each response scenario, utilities should plan for how they can maintain internal, interagency, and external communication . Utilities should practice emergency response exercises regularly and keep track of necessary changes to response protocols. During these exercises reserve time to monitor which staff have access to key entry points at the utility. Successful security programs will also build and maintain a close relationship with local law enforcement. This relationship will allow utilities to respond swiftly and efficiently in coordination with law enforcement when suspicious activity does occur. Remember that final goal of these measures is to prevent any interruption in services, damage to infrastructure, and safety threats to staff and the community. For more information on Malevolent Acts check out the EPA’s Baseline Information on Malevolent Acts for Community Water Systems .