Why Is No One Working Where Traffic Is Restricted?

Six pm. Traffic stalled on Sepulveda Bl. You’ve listened to every CD in your car. You’ve heard enough news about the Euro. Even the extended version of Stairway to Heaven bores you.

You look to your right and see K-rail running along Sepulveda. The road has been shrunk to create a work area, but no one is working. Doesn’t anyone consider how construction affects traffic?

Well, yes.

Although it might seem random to the harassed driver, traffic control in a construction area—especially an area as congested as the Sepulveda Pass—is more science than art. Traffic management plans for the I-405 Sepulveda Pass Improvements Project are dictated by the Los Angeles Department of Transportation (DOT) for City streets and by Caltrans for freeways and their ramps.

“We are working with the City and Caltrans to ensure that the closures we set meet the Manual Uniform Traffic Control Devices (MUTCD) standards,” explains John Trevino, manager of Kiewit’s Maintenance of Traffic team. “The MUTCD is the federal standard for temporary lane closures.”

Traffic control drawings are very detailed, so residents who ask crews to move cones on their street for “just a minute” will likely hear a “no.”

The traffic plan juggles frequently conflicting goals, such as:

• Drivers want to reach their destination as quickly as possible.
• DOT wants Los Angeles drivers to safely and smoothly navigate the construction zone.
• Metro and Caltrans want to complete the project as rapidly as possible.
• Kiewit requires access to work areas from City streets and closed freeway lanes.

The traffic plan also incorporates the psychology of drivers and their reaction times. For example, one lane of an off-ramp may be closed (called a partial closure) to prevent drivers from two off-ramp lanes having to quickly merge into a single lane of a major street. This happens frequently at the Montana Av/Sepulveda intersection.

At the crucial Wilshire Bl/Sepulveda intersection, for example, a long tapering of lanes leaving Wilshire is required because safety standards prohibit tapering a lane immediately after a major intersection.

“We actually have a table on how long a merge taper must be—including cones and signs facing traffic—based on the local speed limit,” Trevino says. “It’s really all based on speed and stopping sight distance.”

The pattern of closures anticipates how long it takes drivers to move from a closed to an open lane or how far ahead of a curve drivers need to prepare for a closed lane. Allowing faster vehicle speeds comes second to safety for drivers and work crews.

This concern for safety means that work zones often include empty spaces, creating a buffer between workers and live traffic. For an activity such as saw-cutting pavement, a crew must move from one section to another, but that entire area must be free of vehicles.

A perfectly good lane might be closed not because of work at street level but because a crew up an adjoining hillside might be clearing vegetation. Safety requires an area for pieces to fall without harming drivers. This situation prompts closures of the southbound Getty Center Dr ramps.

The traffic plan might also require the merging of two short work areas into a longer lane closure, so drivers will not weave in and out of the short work areas.

Construction vehicles, such as large trucks, need a length of lane to accelerate to freeway speed from work areas. This happens frequently in Segment 3 near the Skirball and Mulholland bridges.

All these requirements mean hours are spent just configuring the temporary closures. Trevino estimates that Kiewit and its subcontractors place 1,400 cones on an average night.

K-rail causes its own perception of inactivity. Weighing 3.9 tons apiece, the rails cannot be quickly or easily moved. Consequently, K-rail needed only for night work may be left in place during daytime hours.

Sometimes cones and signs and barriers linger because crews are working somewhere else. For night work, eight crews set up an average of 40 closures each night, five closures per team. When it comes to picking up traffic management tools, the crew responsible might be far away. Also, the crew working on the street may not be the crew trained to put the street back in order.

Here are other reasons work areas might be lacking workers:

• Finishing work early
• Waiting for deliveries (concrete, asphalt, beams)
• Waiting for inspection by the City or Caltrans or Metro
• Waiting for concrete streets to cure (2 hours)
• Waiting for asphalt to cool (2 to 4 hours)
• Waiting for work by other organizations (Exxon-Mobile, Verizon)
• Taking lunch
• Taking two required breaks each work day

Perhaps someone has recorded an audio CD based on the Manual Uniform Traffic Control Devices standards—something new to listen to when you’re stuck in traffic.

Ned Racine