The Sierra Club believes that much of Utah's drinking water could be at risk unless Congress approves a bill to strengthen the Clean Water Act.

The environmental group released a national report Tuesday that lists Utah as the most at-risk state in the nation for dirty drinking water. The risk stems from recent U.S. Supreme Court rulings and a 2003 memorandum by the U.S. Army Corps of Engineers and U.S. Environmental Protection Agency that gave inspectors more leeway in determining whether "non-navigable" and non-permanent sources of water such as Utah's streams and wetlands should be regulated.

Marc Heileson, regional representative for the Sierra Club, said that because of the Bush administration's policies, Utah watersheds could become unregulated and drinking water unclean because streams and waters that don't flow year-round could lose Clean Water Act protections. In Utah, 79 percent of surface drinking water intakes are from such streams, he said, and 90 percent of Utahns get their drinking water from those sources.