Earlier this month, the House Transportation & Infrastructure Committee and the Senate Environment and Public Works Committee held a rare, joint hearing on EPA’s rulemaking concerning its jurisdiction under the Clean Water Act. The hearing was focused on the impacts of the rule to state and local governments that represented the second panel of witnesses. Witnesses, US Army Corps of Engineers Secretary Jo-Ellen Darcy and EPA Administrator Gina McCarthy both insisted that ditches, small ponds and irrigated farmlands would not be subject to federal regulation unless their flow into navigable waters is "significant," but failed to define that term. The proposed rule allows agency discretion to determine if there is a significant effect by looking at the aggregate effect of similar features over a large area. McCarthy and Darcy appealed to science (hydrology) and the need for the federal government to have clearer and more efficient definitions, but senators and representatives from both sides expressed skepticism that the rule would ultimately do that. Administrator McCarthy stuck to the current deadline of Spring 2015 for issuance, dismissed allowing the public to review and comment on the proposed changes before they go into effect and did not elaborate on what changes were being made.

Oklahoma Attorney General Scott Pruitt testified that "the EPA has been generally dismissive of these concerns brought by states, local governments and individual citizens, with their primary tactic being an ineffective public relations campaign to sway opinions in rural America. EPA Administrator Gina McCarthy has been documented as dismissing many concerns wholesale — calling them ‘ludicrous’ and ‘silly’ — while also asserting that the proposed rule is all about "protecting waters" and providing clarification." Other state and local government witnesses also expressed concerns about their lack of involvement in the development of the rule and their concerns over the complexity of implementation."