The Gresham Implementation Plan is presented as an example of an approvable
TMDL implementation plan for a large to medium size municipal designated
management agency (DMA). This implementation plan may serve as a template for
other cities and counties with similar responsibilities, especially those with a
Municipal Separate Storm Sewer System Permit (MS4 Permit) – to restore the
quality of impaired waterbodies and to protect human health, aquatic life, and
other beneficial uses associated with these water resources.
The City of Gresham environmental program staff developed a TMDL
Implementation Plan (IP) for TMDLs in the Willamette and Sandy River
Basins. Specifically, Gresham staff developed an implementation plan
that addresses permit and TMDL requirements for four separate TMDLs, in
five watersheds, covering 10 water quality parameters. The
implementation plan combines narrative sections (Volume 1 - Overview,
Volume 2 – Nonpoint Source Bactieria IP, and Volume 3 – Nonpoint Source
Temperature IP) with a matrix (Table 3) that is the core of the plan.
- Volume 1
The Overview volume describes Gresham’s specific jurisdictional
situation with multiple watersheds and TMDLs.
- Volume 2
the Nonpoint Source Bacteria Implementation Plan Gresham identified
implementation plan measures to address bacteria from sources not
covered by the MS4 permit but within the City’s boundaries.
- Volume 3
In the Nonpoint Source Temperature Implementation Plan Gresham
documented a strategy to protect and restore streamside vegetation
throughout its jurisdiction.
- Table 3 of the plan (xls) (pdf)
Provides a summary of implementation measures and associated regulatory
drivers. Gresham’s commitment to implement each measure and performance
measures to evaluate progress are clearly detailed in the table. It is
expected that this comprehensive approach to TMDL implementation will
strengthen linkages of multiple regulatory programs, facilitate adaptive
management of the watersheds within the City’s jurisdiction, and streamline
regulatory reporting requirements.
There are several benefits with this implementation plan format:
- The Narrative sections meet regulatory requirements
- The Narrative sections can be tailored to meet a DMA’s specific situation
- The Narrative can describe changes over time from the original plan
- The Matrix simplifies and summarizes federal, state, and local regulatory
programs into a single document
- The Matrix can be submitted annually to fulfill reporting needs for both
municipal separate storm sewer system (MS4) permit and TMDLs
- The Matrix can be easily updated over time
- The Matrix can track and assess the DMA’s surface water protection and
A Model Process for
Developing TMDL Implementation Plans