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July 24, 2019

Guardrail work on Lee Hill Drive requires daytime road closures and fulltime bicycling restrictions

Restrictions in place due to narrow, steep working conditions

Boulder County, Colo. - Beginning at 8 a.m. on Monday, July 29, Boulder County Transportation and its contractor will begin a moment slab guardrail installation project that will require a full closure of Lee Hill Drive west of Olde Stage Road. The road will be closed to all travel from 8 a.m. to 4:30 p.m., Monday through Friday, and fully closed to bicycling (24/7). Anyone violating the restriction could be subject to citation by the Boulder County Sheriff’s Office. The project is slated to last into November, but staff will attempt to lift the travel restrictions as soon as possible.

A two-way traffic signal will be installed to safely move motor vehicles around the work zone when the road is returned to a single-lane configuration after working hours. It is imperative that everyone obeys the traffic signal to avoid a potential head-on crash.

The restriction is being enacted due to safety concerns associated with an extremely narrow and confined workspace. Engineers and construction personnel have closely examined the guardrail designs and the location and have determined the only safe way to complete this operation is to close the road. Boulder County apologizes for the inconvenience. Crews will be constructing a moment slab guardrail system which entails completely removing the outside lane of the road in-order-to form a massive concrete slab that the guardrail will then be connected to.

Bicycles are being restricted full-time due to the narrow confines, steepness of the road, and length of the project zone. The lane closure and construction zone will be more than 2000-feet long in an area with significantly steep grades. Traffic signals will need to be set so the slowest traveler heading uphill can safely clear the zone. If cyclists are allowed to ride through the signalized area, the estimated wait would be 20-plus minutes in each direction.

During construction hours, the available lane will be used by construction equipment and personnel. Crews will be equipped with emergency radios in order to clear the area as soon as a call is made for emergency response.

Boulder County Transportation thanks everyone for abiding by the restrictions. We understand how important and popular Lee Hill is for residents and cycling and we will do our best to lift the restrictions as soon as possible.

Courtesy is Contagious
Boulder County is asking for patience and understanding while the restriction is in place. Mountain roads currently under repair are seeing a heavy volume of large trucks and machinery, which makes travel difficult for all modes.

Sunshine, Lefthand, and canyon roads that are open to all modes are likely to see a large increase in cycling activity during the work in other canyons. The county is urging all drivers and cyclists to please be aware of their surroundings and other roadway users at all times. State law requires motorists to provide three-feet of space when passing cyclists and permits motorists to cross the double yellow line to do so. If at a particular location it is not possible to give cyclists three feet of space to pass, motorists are required to wait to pass until they can safely do so. Cyclists have a right to the road, but may only ride two abreast if it does not impede the flow of traffic. Boulder County recommends that all cyclists ride single-file in curves on mountain roads where it is not possible to ride two abreast in the shoulder.

While Boulder County Transportation strives to complete all projects on-time, work is weather dependent and there may be delays due to rain.

For more information on this project, contact Andrew Barth, Transportation Department communications specialist, at or call 303-441-1032.

All current Boulder County Transportation roadway project information, including regular maintenance and flood-recovery activity, can be found at

Map of affected area

Photo of Lee Hill area to be under construction