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Water Resource Inventory Area 13 (WRIA 13)

The WRIA 13 Watershed Management Project brought together citizens, local governments, the Squaxin Island Tribe, and state and federal agencies to attempt to develop a plan for allocating water, protecting water quality, and restoring fish habitat. The watershed planning effort was performed under the guidelines of state RCW 90.82, known as the "Watershed Planning Act," with funding support from the state Department of Ecology.

The WRIA 13 Planning Committee met for several years, from 1999 to 2004, however, the plan fell one-vote short of the unanimous vote needed for the plan to proceed onto the next level of adoption. (State law requires a unanimous vote by all committee members before a plan is brought to governments for adoption.)

Draft WRIA 13 Watershed Plan

Watershed Assessment for WRIA 13

Existing information on water resources topics was compiled in the WRIA 13 Watershed Assessment. This document was intended to be refined as additional information and analysis became available.

Topics in the Assessment included groundwater, surface water hydrology, water quality and water rights. Existing water resource management plans and monitoring data sources were also summarized, to help ensure that the Watershed Plan and future resource management efforts fully utilized the extensive framework of existing plans and data.

Assessment Chapter 1 - Introduction (PDF)
Assessment Chapter 2 - Existing Plans, Programs & Data (PDF)
Assessment Chapter 3 - Land Use Current & Future (PDF)
Assessment Chapter 4 - Geology and Groundwater (PDF)
Assessment Chapter 5 - Surface Water (PDF)
Assessment Chapter 6 - Water Quality (PDF)
Assessment Chapter 7 - Water Rights (PDF)

To learn more about the Washington Department of Ecology's water quality improvement efforts, and to read their frequently asked questions about Total Maximum Daily Load (TMDL) visit their website.

Technical Studies for WRIA 13

Technical studies were undertaken to support the WRIA 13 Planning process. The studies were funded by Watershed Planning grants from the Department of Ecology. Technical studies sponsored by the WRIA 13 Planning effort included:

  • Deschutes River groundwater/streamflow interaction study conducted by Thurston County Environmental Health. Reaches of the river that "gain" or "lose" to groundwater were identified through intensive field investigation.
  • Water rights mapping and initial assessment project. Existing land use was compared to the "Purpose" assigned to water rights, to provide an initial assessment of actual use versus potentially outdated water right documents.
  • Streamflow study for Woodland Creek. An existing hydrologic (streamflow) model of Woodland Creek was updated by a consultant to include a 1950’s model. This provides a basis to better assess impacts on streamflow from development, as there was little urban development in the watershed in 1950. The feasibility of adopting a "target" flow for the creek is assessed.

Technical Documents for WRIA 13

Mitigating ISF Impacts Power Point (PDF)
Deschutes River Groundwater Inflow Study Final Report (PDF)
Henderson Inlet Initial Watershed Assessment (PDF)
WRIA 13 Water Right Mapping Project (PDF)