Story last updated at 1:10 PM on Thursday, December 1, 2005

Stop Light 101: Homer’s first full signal ready to go


The stop toward the End of the Road gets a few miles shorter next week. Drivers used to cruising straight down the Sterling Highway from Kalifornsky Beach Road in Soldotna to Land’s End on the Homer Spit might have to put on the brakes at Lake Street starting next week.

Homer’s long-awaited full-signal traffic light will go on around Dec. 6, said Jason Baxley of the Alaska Department of Transportation and Public Facilities.

Everything is ready to go to run the signal, Baxley said. A subcontractor could have timed the controller earlier, but DOT wanted to have its crews on hand next week to learn about timing the signal. The signal will be maintained by DOT workers out of the Soldotna office, with funding for maintenance coming out of DOT’s budget.

Drivers who haven’t been north of Kasilof in a long time may need a refresher course in stop lights. It’s simple: The red light means stop. The green light means go.

And no, for those who polished their urban driving skills in Anchorage, the yellow light does not mean “punch it.” It means slow down, for the light is about to turn red.

Homer Police Chief Mark Robl said he doesn’t think Homer drivers will need to take Stop Light 101.

“I think everyone around here has driven in big cities with traffic signals,” he said.

So how will the new light work?

The Lake Street and Sterling Highway signal controls traffic for drivers heading both directions on the highway, turning left from the highway onto Lake Street, turning left from Lake Street toward the Spit and turning right from the highway and from Lake Street.

The signal runs all hours of the day and year, Baxley said. The light is green for the highway and red for Lake Street until a driver pulls up wanting to turn left in either direction. Unlike timed signals in big cities, the new signal is tripped by cars and trucks moving over an electromagnetic wire loop buried in the road.

When a driver wanting to take a left from Lake Street onto the highway comes up to the light, for example, the car breaks the loop’s circuit and alerts a computer controller in a nearby equipment box, which then starts a traffic cycle to allow the car to make a left turn.

The wait time for the light to change to a green left-turn arrow is anywhere from 32 to 67 seconds, said Charlie Wagner, a traffic engineer with DOT in Anchorage. Engin-eers calculate about four seconds for the first driver in a row to realize the light has changed and move through the intersection. Cars coming up to a light and already moving take about 2.1 seconds to move through the intersection. The minimum time to turn is 10 seconds — about four cars — and the time allowed can run up to 20 seconds.

Cars taking a left turn from the Sterling Highway onto Lake Street have a permitted green. That is, if the light is a green ball, after yielding to oncoming traffic, drivers can make a turn onto Lake Street. The detection loops have a two- to four-second delay to account for false calls — say if a car travels over another lane’s loop when making a turn, Wagner said. If a car making a left turn onto Lake Street isn’t delayed, the command for flipping a left-turn signal goes away after the car has turned. If one or more cars are delayed, within 20 to 30 seconds those cars get a left-arrow green signal.

A right turn on red is permitted on both streets. The driver must stop, and can turn after it’s safe to do so.

Pedestrians won’t have to play chicken with 18-wheel tractor-trailers to cross at Lake Street and the Sterling Highway. They can stop traffic by pushing buttons at either crosswalk.

Engineers haven’t calculated the signal time yet, Wagner said, but they base it on an average crossing speed of four feet per second. Thus, if the crosswalk is 40-feet long, engineers will set the signal for 10 seconds. Wagner said engineers will take crosswalk measurements and set the pedestrian signal timing next week. If a pedestrian doesn’t push the crossing button, the green walking figure light is on for seven seconds, so Wagner advises pedestrians to push the button to trigger the longer crossing time.

As part of installing the signal, DOT will post caution signs warning of a new traffic pattern, Baxley said. Police will be helping with the transition, Robl said.

“We’ll keep an extra close eye on the intersection until people get used to it,” he said.

Several traffic laws apply to signaled intersections, Robl said. Those include failure to yield to pedestrians in crosswalks, stopping in a crosswalk and, of course, running a red light — defined as a vehicle being past the crosswalk and in the intersection when the light turns red. If the light turns yellow, drivers have enough time to get through the intersection, Robl said.

“Police officers usually don’t take the excuse, ‘Officer, it just turned red when I was turning,’” he said.

The fines for traffic signal violations run from $75 to $150, Robl said.

If power goes out and the signal goes dark, the signal is treated like an all-way stop, as at Lake Street and Pioneer Avenue, Wagner said. Every driver must stop, yield to traffic that has the right of way and proceed when safe. If the signal is broken, as with a power surge, it will go into flashing mode, with a blinking yellow light on the Sterling Highway and a blinking red light on Lake Street, Wagner said. The signal controller can’t automatically alert Soldotna DOT workers that it’s broken.

“We count on input that it’s not operating,” Wagner said.

He asked that if the signal malfunctions for people to call Homer Police at 235-3150 or the local DOT office at 235-5217.

DOT maintenance workers will be adjusting the timing over the next year and make periodic field inspections of the signal and controller at least once a year.

Once the signal is installed and timed, drivers shouldn’t have much of a wait, even at the height of tourist season. Assuming a vehicle is at every loop in the intersection and traffic is at full capacity, the maximum wait at any light is 90 seconds, Wagner said.

“We urge everyone to use caution and get used to the new flow it creates,” Robl said of the new traffic signal.

For those who really do need a refresher course, the Alaska Driver Manual is available at the Alaska Division of Motor Vehicles office or online at www.state.ak. us/local/akpages/ADMIN/dmv/dlmanual/ manuals.htm.