Impact on Vehicle Flow Just a Guess

It may come as a surprise to Orange County voters, but neither county traffic planners nor the people who drafted the Citizens’ Sensible Growth and Traffic Control Initiative have ever studied the measure’s potential impact on traffic flow.

“Until we understand all of the applicable tools and requirements, we are unable to take a position on whether this will work or not,” said Steve Hogan, the chief traffic planner at the county’s Environmental Management Agency. “We have to come to some sort of conclusion, but I can’t say we have. We have not looked at that impact at any level of detail.”

The county’s traffic analysis system is geared toward matching road projects with travel demand--not toward superimposing new traffic flow standards on existing road networks, Hogan said.

“We project demand and we try to accommodate demand, and that obviously does not respect the issue of performance standards, although we are concerned when service levels deteriorate,” Hogan said.

Still, county officials have identified 28 intersections and 12 miles of arterial highway links that may have to be improved before any nearby major development could occur under the initiative--at an estimated cost of $51.5 million. Even Hogan acknowledged, however, that some of the improvements included in that figure would be made without the initiative and that some are already being financed by developers.

At some intersections, Hogan said, motorists would notice little improvement even after major “fixes” are made. Most of the 28 intersections identified by the county may fit into that category because many of them are within half-mile of a freeway, where traffic backs up due to ramp metering that is beyond the county’s control.

“In those locations, the freeway really controls what happens out on the arterial,” Hogan said. He cited the intersection of Rockfield Avenue and El Toro Road in Mission Viejo, one major focus of slow-growth activists.

“No matter what we do at El Toro at Rockfield, the average person won’t see a significant change because of the backup from the freeway.”

Russ Burkett, a key member of the group that drafted the slow-growth initiative, confirmed that proponents have not studied its potential impact on traffic flow.

Burkett acknowledged that improvements may be spotty. He said independent experts wanted too much money for an analysis, so his group relied upon informal talks with engineers in various city traffic departments, and even with some county employees. He declined to identify the engineers.

“They told us the initiative’s standards can work, so we went ahead with them,” Burkett said. “But these people were afraid their superiors would be upset with them for even talking to us.

“There’s a mentality in the (traffic engineering) profession that says you must stay friendly with developers and that intersections must be used beyond their design capacity in order to get your money’s worth out of them. They argue economics, but meanwhile, the poor citizen stays stuck in traffic.”

Some traffic engineers in Irvine, Newport Beach and the county’s Environmental Management Agency said they agree with Burkett’s statement, but they wouldn’t speak for the record.

Hogan would say only that the county’s policy is to identify deficiencies in the road system’s capacity and then try to fix them.

“Obviously, we’re trying to complete new projects that close gaps in the road network. Under the current scheme of things, retrofitting an older intersection that is in trouble (overburdened) may take longer, but an intersection like El Toro and Rockfield is high on our priority list.”

One of the provisions of the slow-growth initiative would require the county to change the way it gauges traffic. Currently, traffic volume is measured and then compared to the road or intersection’s designed capacity. The new system, contained in the 1985 federal highway manual, would require traffic engineers to measure average vehicle delay down to half a second.

UC Berkeley urban planning and transportation expert Elizabeth Deakin, among others, doubts that traffic engineers will be able to measure half-seconds of delay.

“In general, we tell people that if you can get a measurement that is accurate within 5% or 10% (using whole seconds), you’re doing pretty well,” she said.

But others disagreed, pointing out that traffic engineers in Los Angeles and other cities throughout the United States already use the new system.

Hogan, the county traffic planner, said county traffic crews have been testing the new “seconds of delay” measuring system in the field.

It works, he said, except that the results are inconsistent, making it difficult to calculate meaningful averages. Such problems mean it may take weeks or months to get the same numbers to pop up in any sort of recognizable, usable pattern, and that is costly.

“We’ll keep trying,” Hogan said. “If this thing becomes law, we have to get it right.”