In late April, at the same time it released the draft Waters of the U.S. rule, the U.S. Environmental Protection Agency (EPA) published an interpretive rule that went into effect immediately. The rule clarifies the scope of agriculture, forestry, and ranching exemptions to dredge-and-fill permits issued under Section 404 of the Clean Water Act. It includes 56 agricultural conservation practices intended to help protect water quality that will not be subjected to approval from EPA or the U.S. Army Corps of Engineers. These practices are voluntary for farmers and ranchers and are approved by the U.S. Department of Agriculture’s Natural Resources Conservation Service.

The practices, however, could have a negative effect on waterways and may not be consistent with state laws, according to the Association of State Wetlands Managers, Washington Department of Ecology, and others in comments on the interpretive rule. For instance, the practice of clearing and snagging could cause stream bank erosion due to the use of heavy machinery. Some commenters, such as the Southern Environmental Law Center, also said the new rule represents a significant change and should be subject to a public comment period. Read more about the rule and comments here.