The revision by the Environmental Protection Agency and the Army Corps of Engineers was welcomed by the construction industry, which had complained the former rule, issued in 2015, was too broad and could restrict projects.

“Ultimately, we expect the new rule will reduce regulatory uncertainty and bureaucratic confusion, so essential projects needed to improve our infrastructure and the environment are more likely to proceed,” says Brian Turmail, a spokesman for the Associated General Contractors of America. When the draft rule was released in January, the American Road & Transportation Builders Association said it was pleased to see roadside ditches were specifically excluded from federal jurisdiction.

The new navigable waters rule lists four categories of waters that would be subject to federal jurisdiction: territorial seas and waters used in interstate or foreign commerce; certain tributaries; lakes and ponds; and wetlands that abut any of the other three types of waters.

The rule also specifies 12 sorts of waters that would not be subject to federal regulation. Among them are ephemeral streams and similar bodies of water, groundwater, ditches, previously converted cropland, artificial lakes and ponds, constructed stormwater control ponds or other features and “water-filled depressions” that are considered “incidental” to construction or mining activity.

Wetlands must touch another navigable body of water to be considered under federal jurisdiction under the rule.  In some cases, wetlands separated from waters by a constructed feature, such as a levee, might also be judged a federal responsibility.