"Damage to or destruction of the nation's water supply and water quality infrastructure by terrorist attack could disrupt the delivery of vital human services in this country, threatening public health and the environment, or possibly causing loss of life. Interest in such problems has increased since the September 11, 2001, terrorist attacks. Across the country, water infrastructure systems extend over vast areas, and ownership and operation responsibility are both public and private but are overwhelmingly nonfederal. Since the attacks, federal dam operators and water and wastewater utilities have been under heightened security conditions. Most (especially large facilities) have existing emergency plans and coordination mechanisms; at issue now is whether they are sufficient to address serious terrorist threats. Policymakers are considering a number of options, including enhanced physical security, communication and coordination, and research. A key issue is how additional protections and resources directed at public and private sector priorities will be funded. In December Congress approved $345 million in funds for security at water infrastructure facilities (P.L. 107-117), and the House and Senate passed separate versions of bills authorizing new water security programs (H.R. 3178, H.R. 3448, S. 1608). This report will be updated as warranted."