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OSMP Projects

The City of Boulder’s Open Space and Mountain Parks (OSMP) Department will highlight large projects for 2018 on this page. 

Xcel Electric Line Replacement and Trail Projects near NCAR

Xcel Energy is replacing electric transmission line infrastructure on city-owned open space and utility lands. Some trails will have full closures during parts of this project and others may see periodic, daily closures while this work is underway. OSMP will also be doing work along the NCAR-Bear Canyon Trail to complete some of the department’s final 2013 flood-recovery work to repair trails and restore wildlife and plant habitats in the area.

Trail Closures 

Trails Intermittent/Full Closure Closure Dates
- Upper Bear Canyon (west of Mesa Trail)
- This includes many climbing routes in Bear Canyon
Full closure
24 hours/day
7 days/week
8/1 - 12/14**
- Mesa Trail between Mallory Cave and Fern Canyon
- NCAR-Bear Canyon
- NCAR-Bear Connector
Full closure 7 am - 5:30 pm  11/5, 11/6, 11/9, date TBD week of 11/12
- Greenbriar Connector
- Bluestem Connector
- Upper South Fork Shanahan
- Upper North Fork Shanahan
- Mesa Trail between NCAR-Bear Canyon & Bear Canyon
- NCAR-Table Mesa/Bear Full closure  9/4-12/1**
- NCAR-Bear Connector Possible full-day closures 9/4-12/1**
- NCAR-Bear Canyon from Stony Hill access to NCAR-Bear Connector Full closure 8 am to 5 pm, M-F 9/27 to 11/21

*Intermittent closures mean trail users may be stopped by flaggers for up to 15 minutes while materials are flown overhead by helicopter. 

**End date of the project is dependent on weather and other factors and may change. 


More information on trail closures and project updates

Bear Canyon Trail

Starting Wednesday, Aug. 1, the Bear Canyon Trail west of the National Center for Atmospheric Research is closed while Xcel Energy continues work to replace electric transmission line infrastructure on city-owned open space and utility lands. This long-term trail closure west of the Mesa Trail will be in effect 24 hours a day and is expected to continue through November, weather permitting.

NCAR-Table Mesa/Bear Trail

Starting Tuesday, September 4 the NCAR-Table Mesa/Bear Trail will be closed because of Xcel electric construction work. This long-term closure will be in effect 24 hours a day and is expected to continue until December 1. The NCAR-Bear Connector Trail may see intermittent, full-day closures because of this work.

Intermittent closures

The NCAR-Bear Connector may see periodic, full-day closures. Temporary, intermittent closures will still occur on the Mesa Trail between NCAR-Bear Canyon and Bear Canyon, Greenbriar Connector, Bluestem Connector, South Fork Shanahan, and North Fork Shanahan.

NCAR-Bear Canyon Trail - Bear Creek Riparian Restoration Project

Starting September 27, the NCAR-Bear Canyon Trail will be closed 8 am to 5 pm, Monday through Friday, from the Stony Hill access to the NCAR-Bear Connector to complete some of the department’s final 2013 flood-recovery work to repair trails and restore wildlife and plant habitats in the area. This project is expected to last two months. 

Riparian areas (land adjacent to streams) are critical habitat for a variety of wildlife species and plants - click on the photos below to view some of these riparian species. This project involves re-grading the site to make it suitable for planting native shrubs, which are important habitat for the Preble’s meadow jumping mouse (a Federally-listed threatened species), shrub-nesting birds, and other wildlife species. The project is required as per conditions of OSMP’s City wetlands permit, to mitigate for area impacts associated with other trail repairs after the September 2013 flood. Additionally, the project will include a short re-route and drainage improvements to this section of trail.

PlumBlue-gray GnatcatcherChokecherryGolden CurrantSpotted TowheeYellow-breasted chatPreble's meadow jumping mouse

See full photo set in the Photo Gallery

OSMP recognizes that these projects and Xcel’s transmission line work, which will help to maintain transmission line structural integrity and electric reliability in the area, are having an impact on residents and open space visitors. We appreciate your patience while this work continues. OSMP encourages open space visitors to regularly visit to plan alternate routes around these upcoming closures. For more information about work in this area, please contact 303-441-3440.

Eldorado Canyon to Walker Ranch Feasibility Study

OSMP is working with Boulder County Parks and Open Space and Colorado Parks & Wildlife on an Eldorado Canyon to Walker Ranch Feasibility Study. As envisioned, this would be a multi-use trail connection between Eldorado Canyon State Park and the county’s Walker Ranch. A feasibility evaluation analyzing alternatives was started in 2014 but put on hold to investigate acquisition opportunities. 

The feasibility evaluation will re-start in early 2018 and is anticipated to be completed by end of 2018. This effort is being informed by the Boulder Valley Comprehensive Plan and OSMP's Visitor Master Plan, West Trail Study Area Plan and the department's Acquisition Plan. Learn more about the Eldorado Canyon to Walker Ranch Connection Feasibility Study

OSMP Master Plan

OSMP Master Plan logo

Open Space and Mountain Parks has kicked off a long-term effort to establish a community-supported plan that will guide the management of the community’s open space over the next decade and beyond. Share your comments now and sign up for email updates. Our first "window of engagement" for the master plan will close on Friday, March 30.

Rocky Mountain Greenway

The City of Boulder is part of a multi-agency partnership supporting the development of the Rocky Mountain Greenway in Jefferson and Boulder County.   

Information about Open Space and Mountain Parks’ and the Rocky Mountain Greenway
Information about the Rocky Mountain Greenway trail connection between Boulder Open Space and Rocky Flats National Wildlife Refuge

Completed Projects

Boulder Falls

Boulder Falls opened Friday, June 8, 2018. Repairs began in February and included replacing gabion baskets, slope stabilization and trail widening. Additional site improvements will continue in 2019. Thanks for your patience as OSMP works to repair and improve this area.

Boulder Falls Trail construction work Completed Boulder Falls Trail work


South Foothills Trail

In March-May 2018, an OSMP contractor completed repairs of 2/3 mile of the Foothills South Trail from the Utica Ave neighborhood access north to Four Mile Creek. The trail was damaged by the September 2013 flood, which removed the gravel trail surface (crusher fines) and caused erosion. The trail had several drainage features installed to help lessen the potential for future erosion damage. Trail re-construction statistics include:

  • 12 rolling dips constructed on the trail to divert water off of the trail surface and prevent erosion.
  • Over 1400 linear feet of trailside ditch constructed to divert ground surface water away from the trail.
  • The trail surface was re-constructed at 8 feet wide (the same as the pre-construction width), with a 4-inch layer of crusher fines gravel installed as the trail surface.  336 cubic yards of crusher fines (enough to fill 4 ½ city buses!) were used on the project.

Future improvements are scheduled for the Foothills South Trail in upcoming years, including a new bridge over Four Mile Creek, and a short re-route on the section leading down to Wonderland Lake to reduce ongoing erosion issues.

Foothills South Trail before and after reconstruction

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