SOLON– On a typical spring day, just over 11,000 vehicles cross the intersection of Highway and 5th Street in Solon.
Most of them (9,172) are either north or southbound on the Highway. The rest are heading east and west.
But that’s not enough to warrant a traffic signal at the intersection, according to a study by the Metropolitan Planning Organization of Johnson County (MPOJC).
The numbers, presented to the Solon City Council last Wednesday night (Oct. 3), show that the intersection is coming close to reaching the volume level at which a signal might be recommended, but they’re not there yet.
The report also confirmed something most residents already knew; the majority of drivers on Highway 1 exceed the posted speed limit.
Data for the report was collected over four days in March at the request of the city.
Its findings were not enthusiastically greeted.
“Same old news,” reported Mayor Cami Rasmussen.
“I question their accident numbers,” said council member Brad Kunkel. According to the report, only two collisions occurred at the convergence of the two streets between 2008-2010. Kunkel observed the report was likely utilizing data from the state, which only collects information on accidents causing $1,000 or more of damage or in which there was a personal injury.
“I’ll bet there were other property damage accidents that occurred, but didn’t meet the threshold of the $1,000,” he said. Kunkel said he would want a clearer picture of collision data before he accepted the report.
A traffic signal warrant study examines the levels of nine criteria which could prompt the need for a signal. In Solon’s case, only four of the criteria were deemed relevant for the intersection and included in the report. At a minimum, one of the areas must be at the triggering level where a signal would be warranted. “But the satisfaction of a warrant does not in itself require the installation of a signal,” stated the report.
“I think the overwhelming majority of residents here in town, at least the ones who use that intersection, would think we need a stop light up there,” he said.
He advocated at a minimum for a stop light in use during peak morning and afternoon commuting times.
And those are the peaks.
The morning rush hits its highest volume at 7 a.m., when 871 vehicles were counted passing through either on Highway 1 or 5th Street. Between 4 and 6 p.m., the highest counts of the day occur, close to 1,000 motor vehicles. About 90 percent of that traffic is on Highway 1, however, which makes it harder to argue for a signal that would back up traffic on the busiest street in town.
The level of delay for highway traffic is something engineers will take into account, said John Ralston, an assistant transportation planner for MPOJC. Ralston confirmed Kunkel’s suspicion regarding the accident reports, noting only state incident reports were used to compile data.
According to the state, Ralston reported, there were 36 accidents on Highway 1 in Solon’s city limits between 2007-2011, and the largest number (16) were caused by a failure to yield at an intersection. A broadside collision (as is caused by a car turning into traffic) is considered “correctable by a signal,” but five collisions are required to meet the standard for a signal, and Solon’s intersection only had two.
Ralston also noted it was not unusual for traffic to be driving as fast as it is on Highway 1.
According to the report, the 85th percentile speed (the speed of 85 percent of traffic) was 38 miles per hour (mph) for southbound traffic on Highway 1 and 35 mph for northbound. The posted speed limit is 30 mph.
Even if the city were to drop the speed limit on Highway 1, he said, most motorists would continue driving at their own comfort level.