Bottom Slope/Fish Ramp at Ley Creek (pre-existing stone dam on the left)
Streams and lakes in Onondaga County in Central New York area have been significantly altered and degraded as a result of urbanization and industrialization. Located in the Lake Ontario watershed, the area is eligible for funds under the Great Lakes Restoration Initiative for habitat improvements in the watershed. In 2010, the Izaak Walton League of America (IWLA), secured funding under the GLRI for restoration measures in the Onondaga Lake watershed.
Following the successful restoration of Beartrap Creek in Salina, New York in 2010, an additional habitat restoration effort was undertaken in the South Branch of Ley Creek in DeWitt, New York. The Central New York Chapter of the IWLA, in consultation with the Onondaga Environmental Institute (OEI), identified a low head stone dam suspected as acting as an impediment to upstream migration of walleye and northern pike for spring spawning as an opportunity for improvement. Natural Systems Engineering designed a stone bottom slope (or fish ramp) consisting of field stones placed to the toe of the dam to allow fish passage during periods of higher streamflow. Partners on the project include Joe Green Excavating (Phoenix, New York) for construction, OEI for pre- and post-construction biota monitoring, and the Central New York Chapter of the IWLA who was instrumental in site selection and logistics.
Beartrap Creek is a secondary tributary contributing to Onondaga Lake located in Onondaga County, New York. With the growth of the city of Syracuse, the urban development and non-point pollution has been degrading Beartrap Creek. In 2011, a project was designed by Izaak Walton League to address one of the long-term goals of the Great Lakes Restoration Initiative- to provide a healthy ecosystem for fish and wildlife.
Beartrap creek prior to restoration efforts
This project was separated into three subjects:
- Describe the fish community at select locations upstream, downstream, and at sites of restoration in Beartrap Creek before and after habitat enhancements are made, using Rapid Bioassesssment Protocols (RBPs)
- Apply an Index of Biological integrity (IBI) to determine spatial and temporal changes in fish species diversity, density, and size distribution
- Conduct a Visual Habitat Assessment (VHA) of sites before and after construction to determine temporal changes in riparian and in-stream habitat quality
The results of the installation of in-stream structures improved the habitat condition for locations in Beartrap Creek. Based on the IBI, fish community structure was shown to improve at and downstream of habitat enhancements approximately 8-11 months following installation. However for most of those locations improvements were minimal following initial installation, and for all of these sites, IBI scores remained the same or decreased in 2013. Fish richness and diversity was relatively consistent during sample years for each location, with only one location showing a consistent increase in diversity; a site that was upstream of habitat enhancements.
Conclusions were drawn from similar projects that habitat restoration efforts take longer than 2 years to observe the desired outcomes. These sites, as well as others further downstream will be monitored for the next few years with hopes that the restoration efforts have improved the ecosystem.