Row River Nature Park Enhancement Project Background
This vegetation enhancement project takes place at the 56-acre Row River Nature Park. The project area is within the Row River floodplain and around a system of ponds, some of which are connected to the river at high flows. The ponds were created by the extraction of gravel for the construction of Interstate 5 which concluded in 1966. The City of Cottage Grove acquired the site from Mr. and Mrs. Vernon Olsen in three stages between 1973 and 1976. Originally listed on USGS maps as East Regional Park, the park received its current name in 2010, but it is known to locals as the “Cottage Grove Fishing Ponds.”
The Row River Nature Park is located in a relatively pristine section of the Row River. In the reach of river that embraces two sides of the park, there is high quality aquatic habitat as evidenced by the secondary channels, large woody debris, and well-established riparian zones within and adjacent to the park. It is important to utilize the opportunity to restore native ecosystems on lands that will be held in the common trust into perpetuity—like those owned by municipalities and designated with uses like nature recreation and conservation.
Floodplains Provide Multiple Benefits
This city park is a priority area for restoration because of the floodplain connectivity of the Row River. About 20 acres of the restoration area are ponds, backwaters and historic floodplain. These habitats provide refuge for wildlife like the Western pond turtle, as well as native fish and amphibians. These hydrologically active areas support native plant diversity and provide a valuable flood storage purpose.
The ponds and side channels are connected to the Row River at moderate to high flows. The hydrologic connection between the river and its floodplain backwater areas create an ecologically valuable hyporheic zone. The benefits of the hyporheic zone are exchange and filtration of water and nutrients as well as maintenance of cool temperatures. The deep ponds created by the I-5 construction are connected to the river via groundwater and are utilized by pond turtles in summer months.
The U.S. Army Corps of Engineers (USACE) identified the Row River Nature Park as a high priority site for restoration in the 2006 USACE Floodplain Restoration Feasibility Study of the Coast and Middle Fork Willamette River Basins. The USACE Study recommended installation of up to five engineered log jams, excavation of two channels to connect the Row River and floodplain pond system, as well as invasive removal and re-vegetation (Study Reach: R1, Site: C). The CFWWC has begun the first phase of these recommendations and will work with the City and neighboring landowners to explore the most prudent next steps at this site.
Western Pond Turtles Live Here
In the 1990’s, Bill Castillo of ODFW documented a Western pond turtle population of over 30 adults at the park. The US Forest Service and US Army Corps of Engineers conducted a radio-telemetry study and an enhancement project on 2 acres in 2005-2006. Three nesting sites were created, 35 basking logs were placed in four ponds, and radio telemetry confirmed year-round turtle use of the park. The Row River Nature Park Enhancement Project is a continuation of this USFS and USACE project. The habitat restoration of this city park is necessary to sustain and foster the current and future populations of Western pond turtles.
Western Pond Turtles at Risk
Research studies of Western pond turtles indicate that recruitment of juvenile pond turtles is very limited throughout the Willamette River Watershed where riverine habitat is disconnected from upland nesting habitat by roads and other uses. However, due to the long life of turtles as well as their dispersed nesting strategy in some areas, it is possible that there is a larger population cumulatively than it appears. However, at nesting sites and surrounding areas that are predated by native and non-native species (raccoons, bullfrogs, etc.) when adults are able to successfully nest and reproduce, very few juveniles are documented making it to maturity.
Links
- Row River Nature Park Master Plan
- Study links
Project Partners
City of Cottage Grove
US Forest Service – Cottage Grove District
Kennedy Alternative High School Conservations Corps
US Army Corps of Engineers (USACE) – Cottage Grove
Oregon Department of Fish and Wildlife (ODFW)
Oregon Watershed Enhancement Board (OWEB)