Repairs to damage to the Alluvial Fan Trail caused by flooding in September 2013 is underway in Rocky Mountain National Park/NPS

Work is underway in Rocky Mountain National Park in Colorado to repair damage to trails that occurred in September 2013 when torrential rains swept the park.

The Alluvial Fan, Ypsilon Lake, and Lawn Lake trails all sustained substantial damage. While repair work is underway, park officials estimate it will be a few years before the reroutes and repairs are completed on all three trails.

Following the flooding, the park prepared an Environmental Assessment to evaluate alternatives and the potential impacts associated with reestablishing five trails that were badly damaged during the flood: Twin Sisters, Aspen Brook, Alluvial Fan, Ypsilon Lake, and Lawn Lake. The purpose of the EA was to identify potential travel routes while protecting natural and cultural resources and preserving wilderness character. Park staff anticipate that a decision for the Aspen Brook and Twin Sisters trails will be made sometime in 2017.

The NPS selected Alternative B, Establish and Maintain a Travel Route, for the Alluvial Fan, Ypsilon Lake, and Lawn Lake trails because the alternative best met the purpose and need for the project as well as the project objectives. A description of the selected action for the three trails follows.

Lawn Lake Trail – A new trail is being constructed around the four trail sections damaged or washed out, and limited improvements will be made to an existing informal trail. Trail tread will be about 3 feet wide, with trail clearing limits 6 feet wide by 10 feet high. Pedestrian and equestrian use will be allowed.

The 2013 flooding and mudslides exacted quite a bit of damage to the Twin Sisters Trail/NPS

Ypsilon Lake Trail – A new timber foot bridge has been constructed across the Roaring River. New trail approaches on either side of the river are being constructed, with a trail tread about 3 feet wide, and trail clearing limits approximately 6 feet wide by 10 feet high. Pedestrian and equestrian use will be allowed on the trail, but equestrian use will not be allowed on the bridge, instead a horse stream crossing will be established.

Alluvial Fan Trail – A new accessible trail will be constructed between the existing east and west parking lots with a new bridge across the Roaring River. An accessible overlook trail to Horseshoe Falls will be constructed. A 150-foot portion of the accessible trail will extend into designated wilderness to reach the overlook. The trail tread will be about 5 to 6 feet wide, with trail clearing limits approximately 8 feet wide by 8 feet high. Only pedestrian and accessible use will be allowed.