Recently, a few concerns have surfaced regarding the ongoing Department of Transportation and Public Facilities’ construction project to provide continuous highway illumination on Egan Drive from downtown Juneau to Brotherhood Bridge.
The contract for this work was awarded to Ever Electric in August 2013, and site work began in the fall. Work was suspended for much of the 2013-14 winter and resumed this spring. The project is anticipated to be completed later this summer.
This is an important safety project for Southeast Alaska. Egan Drive is not only the busiest highway in Juneau but also the busiest highway in Southeast Alaska, handling between 22,000 to 25,000 vehicles daily.
The Egan Illumination Project was primarily established to address crashes attributable to lack of continuous illumination on Juneau’s principal arterial highway. From 2005 through 2009, the period for which crash data was considered in developing this project, 18 nighttime crashes were recorded on Egan Drive within the project limits of Norway Point to Fred Meyer.
Nearly a third of Egan Drive is already illuminated: downtown from the Douglas Bridge to Norway Point; the retaining wall section near Salmon Creek and Sunny Point Overpass; and Fred Meyer to Mendenhall River. Each of these road segments have overhead lighting including at all intersections. This project fills in the gaps and provides for safer, continuous overhead illumination of the entire corridor.
In recognition that safety was the driving factor for this improvement, the project was advanced under the federally funded Highway Safety Improvement Program. Highway Safety Improvement Program guidance shows that nighttime accidents on unlighted highway segments can be reduced by 25 percent through the installation of continuous illumination. Other research has identified nighttime crash reduction factors varying between 18 and 69 percent, depending on the type of crash.
Continuous illumination on Egan Drive benefits all motorists by improving visibility. Juneau’s long, dark winters — in which visibility is commonly reduced due to heavy rains, winds and snow — were also an important factor in project selection, as was Juneau’s aging population.
Data from the Alaska Department of Labor shows that the Juneau senior population (those over 65) was 9.4 percent of the total population in 2012. This is projected to rise to 16.6 percent in 2016 and 19.5 percent by 2027. The degradation of night vision with age is a challenge many senior drivers face. Additionally, research shows difficulty adjusting vision between dark and illuminated areas as another consequence of aging.
Concerns about light pollution are understandable. However, the lighting fixtures being used on this project are designed and installed to minimize light projection onto areas that don’t need to be illuminated. This was hard-coded into the project during the development phase.
The department also considered using this project as the first large-scale deployment of light-emitting diode (LED) highway illumination on an Alaska state highway. Engineering analysis demonstrated that it was feasible. However, the quality of LED lighting is different than that provided by high-pressure sodium lamps (the current state standard, which also is used on Egan Drive). To provide true uniformity, all existing lighting would have to be replaced with LEDs at substantial extra cost, which could not be justified.
The brighter nature of LED light could also have been more readily deemed obtrusive by some. The department also was not comfortable with large-scale deployment of a new technology on our principal arterial. While not the right fit for Egan Drive, the use of LEDs will continue to be evaluated in upcoming projects.
Improving visibility helps motorists see and be seen. In a related but separate project, the Department of Transportation & Public Facilities will be installing new “Drive with headlights on at all times” signs on a number of highways in Southeast Alaska. In Juneau, these signs will be erected on Glacier Highway (Auke Rec Road to Echo Cove); Thane Road (Old AJ Mine Access Road to end of route in Thane); and North Douglas Highway (Petro Marine driveway to the end of the road).
What may seem a trivial requirement can actually make a significant impact. Data shows that using headlights at all times on certain roadways can reduce crashes by 7 to 15 percent.
Finally, one of our principal responsibilities during construction is to make sure that work zones are safe and orderly for workers and the travelling public.
We wish to thank Juneau motorists, pedestrians and bicyclist for their patience and understanding during this busy construction season.
• Al Clough is Southeast Region Director for the Alaska Department of Transportation and Public Facilities.