In a highly anticipated report, a panel chartered by Congress to advise public agencies on effective governance recommends that the U.S. Environmental Protection Agency revise how it appraises financial burdens when communities are required to upgrade water and sewer systems. Observers say that the revisions, if the EPA accepts them, could change the agency’s permitting and enforcement of municipalities under the Clean Water Act and Safe Drinking Water Act, the bedrock federal environmental laws that occasionally result in multibillion-dollar modifications of water treatment facilities. That means communities could have more time to complete required projects.