The 401 Program uses buffers to attain the reasonable assurances needed to ensure a project will meet state water quality standards. The buffer concept is a widespread tool used across many agencies and municipalities nationwide to aid in the protection of natural resources, and is one component of the review for a project requiring a 401 water quality certification (WQC). This concept is also incorporated into the conditions of the 401 WQC, and once issued, must be adhered to as indicated in the site plans.
The framework for this buffer is consistent with management goals of partner agencies like ODFW (see OAR 635-430-0375(12)), as well as with the DEQ Stormwater Program, which has the same 50' buffer requirement in the 1200-C Construction Stormwater Permit. Similar to the 1200-C Permit, EPA has a set of buffer requirements in Appendix G of their 2017 Construction General Permit. Additionally, Oregon's Department of Land Conservation and Development (DLCD) has developed Statewide Land Use Planning Goals, which include protecting riparian corridors. Collectively, these concepts complement the 401 Program's decision to adopt the 50' buffer as a tool for minimizing degradation, and assuring state water quality standards will be met.
The 401 Program recommends inclusion of all wetland delineations on the construction design plans, so it is clear where impacts are anticipated to occur, and avoidance will be maximized. If there are areas where a 50’ buffer is to be altered, degraded, or minimized, then compensation is necessary to retain the assurances needed to issue a certification. In these cases, providing enhanced buffers can serve as a substitute, as well as providing buffers greater than 50’ in other areas of a project, where there are fewer development constrictions.