Project will facilitate future bike lane on Mesa Road
Starting mid-summer, contractors will install a new electrical conduit system to serve the Mesa Lab. One of the project’s indirect benefits is the option to widen the Mesa Road in the future to incorporate a much-needed bike lane.
This illustration shows the proposed route of the new conduit system. (Image courtesy PPS.)
The current system is made up of two 15-kilovolt feeders consisting of cables installed in conduits or directly buried along the west side of the Mesa Road. Both feeders are well beyond their expected useful lives—one is more than 45 years old, dating back to the lab’s construction. Failure of either feeder would impact the ability to operate the Mesa Lab at current capacity and would necessitate emergency repairs.
Several factors make replacement of either of the current feeders on the existing route impractical, primarily the danger and expense of working in close proximity to the energized feeders, as well as the challenges of handling asbestos fiber conduits.
The proposed route for the new cable (see illustration), which is an approximation, begins one half mile from the bottom of the hill and crosses under the Mesa Road. It then traverses a section of the grassland known as the Horseshoe, before crossing under the road once more close to the lab’s entrance. At this point, it will be routed to the main switchgear in the basement.
The exact route may vary depending on natural drainage systems. The design process will adhere to the National Environmental Policy Act to determine the environmental impacts.
The proposed new route offers a number of advantages over replacing feeders on the old route. It costs less up front and will save money in the long term. It accommodates new telecommunications conduits for eventual upgrades. It will have a minimal impact on the use of the Mesa Lab during construction and allow the lab to operate without power interruption for the majority of the project.
But the advantage most likely to be noticed by staff over time is that the new route will facilitate a future widening of the Mesa Road for a bike lane, although construction plans are not yet in place. “Any road that is shared by motorized vehicles, bicycles, and pedestrians can be hazardous,” says Milenda Powers, UCAR’s health, environment, and safety manager. “Communities have seen real safety improvements for bicycle riders and pedestrians when they can use designated paths, and we would like the same for travel to the Mesa Lab.”
The road’s current configuration allows only for widening on the down-sloping side of the roadway, which would require padding a large portion of that downhill area with structural fill to support additional roadway.
By re-routing the electrical and telecommunications conduits away from the Mesa Road, the existing utilities can be abandoned and the roadway can then be widened on the uphill side. This plan, which consists of cutting into the uphill slope and hauling the materials away, is much less expensive compared to widening the road on the downhill side.
The new route means that the grassland area will be scarred for several years while the area is re-vegetated.
“Our past experience has shown that the area can be restored to its original condition,” says John Pereira, director of Physical Plant Services, pointing to the construction of the ESSL/ACD phytotron on the north side of the Mesa Lab in the 1990s. A temporary construction road of compacted road base and gravel was put in to connect the Mesa Lab road to the phytotron entrance to allow access for construction equipment. Following the completion of the project, the road was removed and the area returned to its natural state through seeding and irrigation.
A similar plan will be included in the design of the new route, John says.