4e Assessments

Category 4e Assessments and Documentation

A waterbody can be placed in category 4e (Ongoing Restoration Activities) if it’s impaired but recently completed or ongoing restoration activities are underway to restore the designated uses of the waterbody. For 4e plans, the waterbody is still included on the 303(d) list, but placement on the Verified List is postponed for one five-year assessment cycle, to allow for implementation of the 4e plan and evaluation of progress toward restoration. If at any time the department determines that reasonable assurance or reasonable progress are not being met, the Verified List will be amended accordingly. This indicates that where a 4e plan is approved, the decision to develop a TMDL is deferred until additional information is submitted to complete the pollutant reduction plan, or until additional water quality data are collected documenting that a waterbody is no longer impaired and consideration for Category 2 (not impaired) is warranted.

The goal of a 4e plan is to implement appropriate restoration activities and, if necessary, additional study so that by the next assessment cycle either a 4b Reasonable Assurance Plan (RAP) can be approved or the waterbody attains water quality standards for the parameter causing the impairment. If the waterbody is still identified as impaired by the next assessment cycle and a 4b plan has not been approved, then the waterbody would likely be placed in Category 5 and included on the Verified List, unless there are additional and substantial restoration efforts scheduled that justify keeping the waterbody in Category 4e for another assessment cycle.

There are a number of benefits to implementing such a plan. First, plan development is locally controlled. Second, an approved plan postpones the development of a TMDL for the impairment by moving straight to restoration activities. Finally, a Category 4e plan enables stakeholders to focus on implementing projects and fixing problems, not on the TMDL process itself. A 4e plan is somewhat more flexible than a 4b RAP but it should describe the goal of the plan (e.g., a 4b RAP will be completed prior to the next assessment cycle and reasonable progress toward restoration will be achieved in the interim, stormwater treatment upgrades have recently been completed that should redress the identified impairment by the next assessment cycle, etc.). Below are a comprehensive list of waterbody-parameter combinations currently assessed in category 4e and links to their supporting documentation.
 

Guidance on Developing Restoration Plans as Alternatives to TMDLs – Assessment Category 4b and 4e Plans

Supporting documentation available upon request.
 

Example waterbodies in Category 4e