Washout around a culvert on Island Park Road. Note person for scale/NPS

Winter flooding has taken out sections of the road leading to Island Park and Rainbow Park in Dinosaur National Monument, and park officials have no firm timetable for when repairs will allow it to reopen.

Monument staff and engineers from the Federal Highway Administration are working to identify immediate fixes that could allow the road to reopen, and longer term solutions to prevent damage in future events. The road experienced two significant events within six months that led to washouts. The road is currently closed near the monument boundary.

The Rainbow Park Campground and boat ramp are inaccessible at this time due to the closure. All single-day river permits for the Split Mountain Canyon section of the Green River are on hold until road repairs are made and the road is reopened.

The recent road assessment revealed areas where flooding has eroded the road down to one, still-eroding lane. The Island Park Road bed was damaged by flooding and the road bed surrounding a ten-foot diameter culvert was washed out. Earth and boulders have slumped from surrounding slopes onto the road and the Rainbow Park Boat Ramp.

National Park Service funding has been obligated to conduct work on the road so that it can be reopened as soon as possible. Because the damage exceeds what monument staff can repair and requires engineering review, staff from the Federal Highways Administration will assist with developing a plan and scope of work for contracting the work.

Engineers are looking into a variety of options to initially open the road including using a temporary bridge. No information is available at this time on a potential reopening date. 

Additional background information:

During a patrol to check on the status of the Island Park Road on Thursday, March 2, a ranger discovered that sections of the road had washed out, including a ten-foot diameter culvert. Staff had not been able to make a check of the road for several weeks due to snow and road surface conditions. After receiving above normal snowfall over the winter, the monument received rain and a rapid warm up on February 20, which most likely caused the flooding event in Stone Bridge Draw and other nearby drainages. The road is not maintained in the winter and has a clay surface in many areas that is extremely soft and slippery when wet.

The road previously was severely damaged on September 23, 2016, during a severe thunderstorm that produced over 2.5 inches of rain in a short period of time. Eight culverts along the road sustained damage or were washed out. The monument, along with staff from the Uintah County Road Department and Rocky Mountain National Park, made temporary repairs to reopen the road.

The Island Park/Rainbow Park Road is a 13-mile unpaved road located on the monument’s northwest corner. It provides access to the Rainbow Park Boat Ramp, which is the launch point for single day rafting trips through Split Mountain Canyon. Also located in this area are the Rainbow Park Campground, McKee Spring Petroglyphs, and the remnants of the historic Ruple Ranch.

This closure does not affect visitor access to the Quarry Visitor Center or the Quarry Exhibit Hall where visitors can see the dinosaur fossils.