Clear Creek Mainstem Project Corridor:

Kearney Gulch to Silver Plume

Projects Overview

The mainstem of Clear Creek is a high priority pre-wildfire preparedness corridor, with water quality and flood risk reduction opportunities identified between Kearney Gulch to the Town of Silver Plume. Projects address opportunities for low-impact reservoir development, beaver complex expansion, and stream and floodplain restoration activities that would provide multiple-benefits. Two potential low-impact reservoirs have been identified in this corridor as part of the Clear Creek County Water Bank study. Field reconnaissance revealed several locations with pinched and degrading channels in project locations identified for restoration by the 2021 pre-wildfire planning study. An historic stream channel analysis was completed for this reach of mainstem Clear Creek in spring 2023; outputs and additional datasets for this reach can be viewed in an ArcGIS Online map app.

Mitigation Measures Proposed

  1. Two potential low-impact reservoirs identified in the Clear Creek County Water Bank (Bakerville Reservoir No. 1 & No. 2) are located in this corridor, both of which are included in the South Platte Basin Implementation Plan. These decreed water rights are held to address the anticipated future water supply and demand gap. The storage sites would additionally serve as flood and sediment controls to protect water facilities infrastructure downstream. Recommend a Multiple Criteria Decision Analysis on Conditional Storage Decrees.

  2. From west of Jazz Place and Silver Valley Road heading east, recommend that the corridor be enhanced using low-tech process-based restoration design to safeguard against flooding and provide sediment controls.

  3. The Brown Gulch drainage west of Silver Plume should be armored to protect the waterway. Immediately to the east of Brown Gulch is the PT Burleigh Millsite. The site is discharging into a settling pond. Recommend water quality and habitat evaluation followed by sediment reduction.

In Spring 2023, a CSM Senior Design Team began a project to evaluate the reach for detailed mitigation considerations. The students were asked to employ several methods to develop an understanding of potential wetland expansion and beaver enhancement in this corridor, including:

  • Develop a matrix of relevant permits and timelines

  • GIS analysis – peak flows, volume, slope factors

  • Geomorphic site suitability checklist - Geomorphic Scoring (scorecards)

  • Beaver Restoration Assessment Tool (BRAT) is an ArcGIS based model that calculates the capacity of a river to support beaver dam building (MacFarlane et al., 2017)

Estimated Costs & Permitting

Estimated costs for these mitigation activities should be developed in separate task orders for the different mitigation measures proposed. Permitting requires further project development and analysis.

Bakerville Reservoir No. 1

  • The Bakerville Reservoirs were identified and scoped in the Clear Creek County Water Bank study, and are included in South Plate Basin Implementation Plan. Bakerville Reservoir No. 1 is in the vicinity of identified project SP-6.

  • A low-impact reservoir could be decreed and constructed to serve as flood and sediment control to protect water infrastructure downstream. The USFS parcel is a high-priority area for tree thinning.

  • Located on United States Forest Service land approximately 1 mile east of the Bakerville exit on Interstate-70, proximate to CDOT Right of Way. Located along Clear Creek south of I-70 between I-70 and Silver Valley Road, the frontage road.

2008 Scoping

  • Dam Crest Length: 534 ft

  • Dam Crest Elevation: 9,896 ft

  • Reservoir Surface Area: 7.6 acres

  • Max Dam Height: 18 ft

  • Max Storage: 68 acre-ft

  1. Low-Impact Reservoirs

Bakerville Reservoir No. 2

  • The Bakerville Reservoirs were identified and scoped in the Clear Creek County Water Bank study, and are included in South Plate Basin Implementation Plan.

  • Located on United States Forest Service land approximately 1 mile west of the Graymont exit of Interstate 70, proximate to I-70 Right of Way.

  • This site is located within the I-70 West Bound Bakerville to EJMT CDOT SWEEP Area. NEPA studies for the CDOT SWEEP area can be included as analysis for project development at this location.

2008 Scoping

  • Dam Crest Length: 557 ft

  • Dam Crest Elevation: 9,896 ft

  • Reservoir Surface Area: 7.6 acres

  • Max Dam Height: 23 ft including 5 ft of freeboard

  • Max Storage: 80 acre-ft

Low-Tech Process-Based Restoration

In 2021, Colorado Parks & Wildlife leadership approved the beaver as a Wetlands Program priority species. This means that wetland/riparian restoration projects which are designed to benefit beavers and their habitats will be considered a higher priority for program funding through the annual wetlands grant cycle.

These projects typically include beaver dam analogs or post-assisted log structures to re-establish woody plant species preferred by beavers, and to incentivize beaves to adopt the area and construct or maintain dams at the project site. Beaver wetlands have wide swaths of soggy land that help spread water and limit downstream flooding. Spreading water across the floodplain has proven benefits for water temperature and quality, in addition to flood control; when water laden with sediment, nitrates, or carbon slows down, particles can settle out or be consumed.

Additional enhancements at this location could include a small parking location for fishing users, for inclusion in the Clear Creek County Recreation Plan.

Colorado School of Mines - 2023 Senior Design Project

Beaver Habitat Development Final Design Report

In spring and fall semesters of 2023, a CSM Senior Design student team is working on the following deliverables in support of mitigation in this project area:

  • Matrix of needed environmental assessments for beaver complex development (e.g. permitting requirements)

  • Geomorphic site suitability assessment using Geomorphic Scoring

  • GIS analysis of Beaver Restoration potential, including peak flows, volume, and slope factors.

  • Preliminary designs for beaver habitat development in the high-priority corridor of Silver Dale Road.

2. Low-Tech Process-Based Restoration

3. Brown Gulch Drainage & Mine Waste in Silver Plume

Brown Gulch Flood Risk & Mine Waste

North of I-70 and east of Silver Valley Rd, Brown Gulch tributaries into Clear Creek. Field reconnaissance shows a steep slope of mine waste that is severely eroded in the vicinity of an identified flood risk reduction project (FR-8). Immediately downstream, in the vicinity of identified project SR-5, the PT Burleigh Millsite discharges into a settling pond which is connected to the mainstem channel of Clear Creek. Project SR-5 recommends armoring the channel to protect against post-fire flows; additional measures for sediment reduction, channel stability, and water quality are recommended.

Flooding at these locations would mobilize a large volume of sediment and cause severe water quality issues associate with the mine waste. CCWFHP is working with the Trout Unlimited Abandoned Mines Program to implement mitigation measures at this location. Mine waste projects may also be impacted by the EPA Clear Creek Superfund Site declaration.