by Dieter Erdmann, Colorado Open Lands
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Photo 1: First day, first meander, 5 hours later. |
Fourmile Creek is a third order tributary to the Middle Fork of the South Platte River in South Park. Like many rivers and streams in the intermountain west, Fourmile Creek’s headwaters are located on public lands. As the stream loses elevation and gradient, it flows through various private ownerships, and land-use impacts begin to occur. Perhaps the most impacted reach of Fourmile Creek is located on 1,952 acres of ranchland owned by Denver Water. Historical photos indicate that the Rosgen type E stream was channelized, probably for agricultural reasons, prior to Denver’s purchase of the property in 1976. Over time, channelization of the creek led to erosion and incision of the creek bed, and ultimately, disconnection of the creek hydrology from the historic floodplain.
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.
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Photo 2: Straightened incised channel on right, newly built channel showing natural stream sinuosity on left, just add water and patience. |
In December of 2002, the North American Wetlands Conservation Council (NAWCA) awarded $1,000,000 to Colorado Open Lands for the South Park Basin Premier Wetlands and Mountain Plover Habitat Protection Project. The purpose of the project was to preserve 6,000 acres of wetlands and associated uplands using conservation easements, and to restore and enhance riparian and upland habitat on the Fourmile Creek property. Colorado Open Lands is one of nearly forty participants in the South Park Wetlands Focus Area Committee, a working group formed in conjunction with the Colorado Division of Wildlife’s (CDOW) Wetlands Program. Colorado Open Lands was able to realize this significant award only through the effort of nearly a dozen Focus Area Committee participants, including private landowners, the CDOW, The Nature Conservancy, the Rocky Mountain Bird Observatory, and Park County. As proposed, the U.S. Fish and Wildlife Service Colorado Partners for Fish and Wildlife Program (PFW) would engineer, design, permit, and implement the Fourmile Creek project. Receipt of the NAWCA award with $200,000 earmarked for the restoration and an additional $100,000 grant from CDOW Wetlands Program allowed work on the Fourmile Creek project to begin.
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.”
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Photo 3: A class photo was taken for the families of the inmates. |
The Buena Vista vocational program, supervised by correctional officers Tom Bowen and Tom Foreman, allows handpicked inmates an opportunity to gain on-the-job training and rehabilitation. Participants in the program are expected to follow rules of behavior that far exceed those imposed on the general prison population. Those who successfully complete the State Contractors Association-endorsed program leave the correctional facility with the skills, ability, and mindset to earn an honest living. Through this program, the partnership was able to obtain the manpower needed to implement the restoration project, leaving enough funds to pay for heavy equipment rental, fuel, and seed. An illustration of the cost savings provided by the vocational program is that while each of the 20 inmates received compensation of 60 cents per day, just one of the six-wheel-drive haulage trucks used cost $22,000 per month, not including fuel.
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:
Graul, W.D. 1973. Adaptive aspects of the Mountain Plover social system. Living Bird 12:69-94.
Knopf, F.L. and B.J. Miller. 1994. Charadrius montanus — montane, grassland, or bare-ground plover? Auk 111:504-506.
Grunau L. and M. Wunder. 2001. Conservation Assessment for Mountain Plover (Charadrius montanus) in South Park, Colorado. Colorado Natural Heritage Program, Fort Collins, CO.