As the rains have reluctantly reached the Oregon coast planting of trees and shrubs along the newly re-meandered Matson Creek main-stem and north fork mark the culmination of fisheries and wetland restoration activities at the Wetland Conservancy’s Coos County property that began in 2004. This third and final phase of restoration was designed to afford full functionality of the lands as overwintering habitat for several migratory species found in the Coos watershed including Coastal Cutthroat Trout, Coho Salmon, Chum Salmon, Winter steelhead, Pacific Lamprey and Western Brook Lamprey.
The project was completed by the Coos Bay North Bend Waterboard under a Memorandum of Understanding with Oregon Department of Fish and Wildlife as mitigation for waivers of fish passage at the Lower and Upper Pony Creek Dams, also located in the Coos Watershed. Fish passage has not been present along the Pony Creek above the Lower dam since it was erected in the 1930s. Since that time, Pony creek below the dam has become increasingly encroached upon by urban development and is listed as a 303d stream for high temperatures. Occasional Cutthroat Trout are the only migratory species observed in Pony. With a mutual desire to provide a meaningful mitigation package with a net benefit to Coastal Cutthroat as well as other migratory species, the Water Board and Charleston ODFW staff selected and designed the restoration at Matson Creek after years of exhaustive searching in the Coos Watershed. According to ODFW biologist Christoffer Claire, the completion of this project may constitute the only fully functional headwaters to ocean system in the Coos Bay system.
The project area encompasses 97 acres of fresh and estuarine habitat located adjacent to Catching Slough off of Coos Bay. Previous restoration phases included the replacement of undersized and failing culverts and tidegates with a bridge for full natural hydraulic connectivity between Matson Creek and Catching Slough as well as the abandonment of ditches and re-establishment of the main stem of Matson Creek through the lower valley.
Activities in the 2015 phase focused efforts up into the north and south valleys above the lower valley and included:
- Removal of non-native vegetation
- Salvage of 1,000 coho
- The abandonment of 10,000 cubic yards of ditches installed in the 1930’s along the north and south valley edges
- The re-establishment of over 5,900 feet of naturally meandering stream bed and side channels through the two valleys
- Placement of over 130 large wood structures to enhance streambank stability, obstruct flow from abandoned ditches and provide habitat
- 4 Acres of stream bank, riparian and floodplain plantings
The Water Board contracted with ESA Vigil Agramis Portland for completion of the final project design. Permitting and project management was completed by Sol Coast Consulting & Design, LLC of Coos Bay. Construction was completed by Billeter Marine, LLC of Coos Bay during the 2015 in-stream season with final plantings completed in November by Cleanrivers, LLC, also of Coos Bay.
Sol Coast and ODFW completed four days of fish salvage from the ditches prior to abandonment. Salvaged fish were held in undisturbed reaches of tributaries to the restored Matson Creek and ultimately released to the creek upon project completion.
By Shannon Souza, PE
Sol Coast Consulting & Design, LLC