The National Park Service and Columbia River Estuary Study Taskforce worked together to restore tidal processes and historical wetland habitat on a 45-acre pasture site within the Lewis and Clark National Historical Park. More than a century ago, the swamp was cleared and drained for agricultural use, and approximately 100,000 cubic yards of dredge spoils from the adjacent Lewis and Clark River were placed across the site.
We appreciate all of the partners who participated in seeing this project through to fruition, and we couldn’t be prouder of our work to restore this important coastal wetland.
In addition to restoring valuable salmon habitat and improving floodplain and wetland function, the Colewort Creek Restoration also helped to recreate the historical landscape of Fort Clatsop. These actions add aesthetic and educational value to the Lewis and Clark National Historical Park, contributing to its mission to recreate landscape features and plant and animal communities comparable to those found there during Lewis and Clark’s Corps of Discovery.
ESA assisted CREST and the National Park Service in designing this 44-acre tidal wetland restoration project. The team’s practical solutions included conceptual design and the development of design alternatives, presentations to a Technical Advisory Committee, preparing final construction documents, and bid-phase and construction-phase services.
Restoration work included over 20,000 cubic yards of earthwork to lower the marsh plain to historic elevations, create over 4,000 linear feet of new tidal channels, and generate mounds and hummocks for spruce swamp plantings. More than 200 logs were installed in wood habitat structures throughout the site, and invasive reed canarygrass was removed from 2.5 acres in the northeastern corner of the wetland. ESA coordinated with the park’s botanist to develop a revegetation strategy that involved planting a variety of native trees, shrubs, and other ecologically important species to reestablish native plant communities. ESA’s ecologically-based strategies successfully restored natural tidal floodplain processes within this historical park.