Wastewater Treatment Works Security Act of 2007

Wastewater Treatment Works Security Act of 2007 - Amends the Federal Water Pollution Control Act to authorize the Administrator of the Environmental Protection Agency (EPA) to provide grants for: (1) vulnerability assessments of publicly owned treatment works; (2) implementation of security enhancements; (3) the development, expansion, or upgrading of emergency response plans and site security plans; and (4) the voluntary creation of mutual aid and emergency network preparedness agreements developed in accordance with the National Incident Management System.

Prescribes disclosure limits and protections for vulnerability assessments.

Limits the federal cost share of an activity funded by grant under this Act to 50%.

Authorizes the Administrator to: (1) provide technical guidance to small publicly owned treatment works (serving fewer than 10,000 individuals) for conducting vulnerability assessments, emergency response plans, or site security plans and for implementing security enhancements; and (2) make grants to nonprofit organizations to improve assessment methodologies and tools for publicly owned treatment works; and (3) make grants to nonprofit organizations to implement a comprehensive training program for treatment works or privately owned utilities that principally treat municipal wastewater.

Requires the Administrator to research and review: (1) means of providing alternative processes to convey, treat, and dispose of wastewater if a disruption of service event occurs; (2) how a collection system of a treatment works could be used to convey hazardous substances and how it could be secured in response to an intentional harmful act; and (3) methods for monitoring a collection system for hazardous substances and unauthorized entry.