The Ohio Environmental Protection Agency (OEPA) is proposing a new rule in the water quality standards chapter of the Ohio Administrative Code (OAC) that establishes a tiered stream mitigation review process and provides detailed stream mitigation procedures. If adopted, the stream mitigation rule would apply whenever someone requests authorization to discharge dredge or fill material to a stream.

Under the new water quality standards rule 3745-1-56, if an applicant proposes impacts to a stream, the company must demonstrate that it has avoided impacts where possible and has minimized impacts that cannot be avoided. If those demonstrations are made, OEPA can approve the impacts if they are mitigated in accordance with the rule.

The draft rule establishes four distinct stream mitigation categories based on their aquatic-life use designations. Mitigation requirements vary with mitigation category, from installing and maintaining best management practices on-site to mitigate the impacts on downstream waters on category 1 streams (inherently low-quality streams) to determining a flexible mix of on-site and off-site mitigation through a debit-credit system for category 3 and 4 streams (inherently higher-quality streams).

OEPA maintains that the stream mitigation rule is needed to establish consistent project review guidelines and assure protective mitigation design approvals for dredge and fill impacts on streams. Currently, without any rule in place, each project is reviewed on an individual basis, applying a minimum of broadly stated objectives on maintaining water quality. OEPA believes this approach has a number of weaknesses, including longer review times, differences in reviewer expectations and variation regarding the capacity of the final mitigation design to adequately protect water quality and stream integrity.

This rule package is the last of four interrelated surface water quality rule packages. The first three rule packages were released for interested party review in the fall of 2008 and address the Water Quality Standards triennial review, Antidegradation, and Section 401 Water Quality Certifications. The release of the Stream Mitigation rule package started a 90-day interested party review comment period for all four rule packages. The comment deadline was March 8, 2011. More information is available at: