WRIA 16/14b Rivers & Streams Impairment Analysis, Mason & Jefferson Counties

Aspect completed an analysis of river and stream impairment, identifying and prioritizing areas of concern for potential impacts of future groundwater withdrawals on streamflows within WRIA 16/14b (along the west and south shores of Hood Canal).

As a key part of this analysis, Aspect developed sophisticated database and GIS analysis toolsets to perform population-based (census data) and source-based (wells, water rights, and public water systems) water use assessments – for both current and buildout conditions in the basin. Beyond helping the WRIA 16 Planning Unit understand and plan for projected water use in the WRIA 16 subbasins, Aspect’s analysis helped identify 13 public waters systems with probable water right shortfalls at full buildout. Additionally, Aspect implemented a GIS-based predictive model to identify sites with a high likelihood for stream sediment aggradation (a critical issue in the WRIA) – evaluating these sites based on stream transport capacity, upstream, in-channel and local sediment supply, and barriers to sediment transport. The software solutions developed as a part of this project allow WRIA stakeholders to execute updated analyses as data inputs (or model assumptions) change or are improved over time. Further, Aspect was responsible for a large cartographic effort on the project, designing over 50 maps and figures for the final report.