Trump administration move will give agencies time to finalize a less-strict replacement Waters of the U.S. rule.

Regulation applies to direct federal contracts after Jan. 1 but some federally funded work, like federal-aid highway contracts, are exempt.

The Federal Aviation Administration has asked an outside committee to propose eased rules for commercial flights of small drones in urban areas and over people not involved in flight operations.

Claiming that pilot sightings of potentially unsafe drone flights have doubled since 2014, the U.S. Transportation Dept. and the Federal Aviation Administration on Oct. 19 said they are taking steps to develop a system to register unmanned aircraft.