New guidelines unveiled by the Bush administration on Friday could spell trouble for 20 million acres of wetlands across the United States. The guidelines were prompted by a 2001 Supreme Court decision that found that isolated, non-navigable ponds and wetlands in Illinois did not merit protection under the Clean Water Act. Environmentalists say that narrow ruling should not be applied to the entire nation, but the U.S. EPA and the U.S. Army Corps of Engineers have ordered their regional offices to withhold protections from similar water bodies and seek federal advice prior to protecting other small, intrastate waterways. As a result, responsibility for protecting as much as 20 percent of the 100 million acres of wetlands in the continental U.S. could be devolved from the federal government to the states. Environmentalists fear that could lead to widespread development of wetlands and mark the beginning of a wholesale weakening of water protections.