|
||||||||||||
|
||||||||||||
|
Editor's Call ARTICLES Fourmile Creek Restoration 120th Avenue Extension A Message from the President Wildlands Restoration Volunteers Annual Meeting Photos FEATURES Legal Developments Research Summaries Volume 15, Number 3 Fall 2004 Volume 15, Number 2 Summer 2004 Volume 15, Number 1 Spring 2004 Volume 14, Number 3 Fall/Winter 2003 Volume 14, Number 2 Summer 2003 Volume 14, Number 1 Spring 2003 Volume 13, Number 3, Fall 2002 PREVIOUS ISSUES |
Fourmile Creek Restoration Projectby Dieter Erdmann, Colorado Open Lands
This process of decline was compounded over time by the utilization of Fourmile Creek as the primary source of stock water for the property and an adjacent Bureau of Land Management (BLM) lease. This tended to concentrate the impacts of cattle grazing around the creek and on the floodplain. Meanwhile, some upland portions of the property and the adjacent BLM land were receiving less utilization by stock. These upland areas had also seen limited use by a declining grassland bird species, Mountain Plover. Research has shown that Mountain Plover can benefit from upland grazing. Historically, the birds have chosen to nests in areas of shortgrass prairie used by large herbivore assemblages such as bison, pronghorn, and prairie dogs. Today, cattle typically create the intensively grazed grassland habitat that Mountain Plover prefer. Mountain Plover nesting sites are a simple scrape in the ground, usually in an area dominated by blue grama (Graul 1973) and at least 30% bare ground (Knopf and Miller 1994). It is believed that South Park may provide breeding and nesting habitat for 10% to 20% of the world's population of Mountain Plover (Grunau and Wonder 2001). Additionally, preliminary research indicates that Mountain Plover in South Park enjoy a higher nesting success rate than in other parts of Colorado (Grunau and Wonder 2001). The Fourmile Creek property is adjacent to The Nature Conservancy's High Creek Fen Preserve, and Nature Conservancy staff were aware of the condition of the property. TNC also recognized that stream restoration, fencing of the channel, and better utilization of the upland grazing resources of the property could benefit both wetland and uplands birds in the area. Restoration would also improve downstream water quality. The Nature Conservancy and Colorado Open Lands approached Denver Water staff in 2001 to gauge the organization's interest in a source water protection/property restoration project. Denver Water enthusiastically endorsed the proposal.
PFW staff began characterizing relatively natural reaches of Fourmile Creek to utilize as reference for project design, and the project partners began to assess the parameters of the project. Nearly 3.5 miles of riffle, with very few in-stream features or natural meanders, ran straight through the floodplain. Appropriately restoring the Fourmile Creek would require abandoning the existing channel and building a new stream from scratch. Faced with this monumental challenge, it began to dawn on the project partners that we might not be able to meet our collective objectives with a $300,000 budget. Nevertheless, the PFW hydrologist proceeded to design the project, in the hopes that it could be fully implemented. To assist in this effort, Denver Water flew the property and generated a six-inch contour interval map from aerial photography for design purposes. Bob Timberman, a PFW biologist and the manager of the Fourmile Creek restoration project, recounts, "With the scope and complexity of the project, it was beginning to look like an impossible situation. That's when I learned of the Vocational School Heavy Equipment Program run out of the Buena Vista correctional facility."
As the solution to the project budget restriction was identified, the Partners for Fish and Wildlife Program hydrologist rolled out the restoration plan that increased the length of Fourmile Creek on the Denver Water property from 3.5 miles to just under 5 miles. This was accomplished through the creation of natural stream meanders and stream feature spacing. Meander and feature spacing information was obtained from the reference reach data gathered previously. The bottom of the creek-bed would be elevated throughout the property in an attempt to reconnect the stream hydrology with the floodplain. Every riffle, run, pool and glide was to be built to project specifications. It was agreed that the creek corridor would be fenced roughly 150 feet from each side of the new creek channel, and the grazing within this corridor would be restricted. In addition, both Denver Water and the BLM would establish off-stream stock watering locations on each side of the creek to allow increased utilization of the upland portions of the property. In early spring of 2004 the project layout was surveyed and flagged by Merrick and Company, an independent surveying contractor. Construction began in mid-June and continued full-time for twelve weeks. Four crews worked simultaneously on new channel construction, each crew consisting of an excavator, a haulage truck, and a survey ground team working in concert. A fifth crew worked on project layout operations, and a sixth worked exclusively on day-to-day equipment maintenance. Crew members would switch crews and responsibilities regularly to expose them to all aspects of equipment operation and project implementation. Due primarily to the need to get the stream out of its undercut and incised channel and reconnected to the floodplain hydrology, it was necessary to construct an entirely new channel in lieu of actually re-meandering the existing channel. This approach will allow for careful management of flows through the new channel, and for excess flow to be diverted through the old, straight channel. This in turn will help protect raw banks from high flow events while protective vegetation is established. Bob Timberman credits the Vocational Heavy Equipment Training Program for making the project a success: "Even though the inmates began the project with little or no experience with heavy equipment operation, using survey instruments, or reading design plans and spreadsheets, the project was completed on time, on budget, accurately, and safely. The level of responsibility and dedication that was required of the inmate crew to complete the task according to specifications should serve them well when released." Some work still remains to be completed at the Fourmile restoration site. Fencing and off-stream watering work is currently in progress. All partners enthusiastically await the initial introduction of water to the system at the beginning of the next growing season. Rocky Mountain Bird Observatory has established vegetation and passerine bird monitoring transects on the property, and other monitoring efforts are being established. Project partners anticipate that these monitoring efforts will demonstrate that the project will be a success. Dan Pike, President of Colorado Open Lands, stated: "This project has been an entirely new direction for Colorado Open Lands. Thanks to the tireless effort of the Partners for Fish and Wildlife Program and the commitment of the Denver Water and the BLM we have been able to exceed our obligations to NAWCA and deliver a project with diverse benefits to all involved." Don Kennedy, a Denver Water Environmental Planner who helped coordinate the project, agreed: "The Fourmile Creek restoration has really been a great accomplishment for our organization. This collaboration is beneficial to all of our interests. By limiting cattle use along the creek, through better livestock management practices, and by reducing erosion in the stream channel we are protecting the water source for our customers. If we can simultaneously enhance habitat for both wetland and upland birds, then we have created a win-win situation." Literature Cited: | |||||||||||
| Posted on December 24, 2004. |