Mill Pond Dam, in place in various forms since 1909, is being removed as part of Seattle City Light’s FERC relicensing requirements for the Boundary Hydroelectric Project, allowing the natural riverine ecosystem structure and functions to be restored.
This work will facilitate natural stream functions; support fish passage; and restore native wetland, riparian, and upland vegetation zones. It also will improve long-term habitat and recreational opportunities.
We are a partner in the design-build project of removing the 55-foot-tall Mill Pond Dam on Sullivan Creek, a tributary to the Pend Oreille River in northeast Washington.
ESA is responsible for all permitting, National Environmental Policy Act, and Endangered Species Act compliance; restoration design and implementation for the upland, wetland, and riparian habitats behind the dam following demolition; restoration of all staging areas; design of recreation and interpretative elements; and monitoring of plantings to meet performance standards.
Field assessments of nearby reference sites were used to design the planting scheme; seed and plant collection strategy; and nursery grow, delivery, and planting plan. Our ecologists and hydrologists worked closely with a stakeholder group and the Colville National Forest staff to design and implement the restoration plan and permit requirements. A recreation site plan, developed in coordination with these stakeholders and the public, includes several trails through the existing reservoir, stream access points, interpretive signs, and picnic areas. We participated in numerous public and stakeholder meetings throughout the process.
Following removal of the dam in fall 2017, our restoration team evaluated the drained reservoir bed and worked with the planting team to adjust the restoration design as needed. Work continues through 2019, including the monitoring of vegetation, trails, facilities, and interpretive signage are installed and perform as designed.
INITIAL PHASE OF CONSTRUCTION
One of the more enlightening moments in stream restoration is when a recently constructed site experiences a large storm event. Whether these events test a restoration design approach or trigger system adjustment, they are always an opportunity to learn.