The invisible high crash traffic sign in Solon Ohio

City of Solon and Ohio Department of Transportation conducted a study to determine the effectiveness of a MUTCD non-compliant HIGH CRASH LOCATION-FOLLOWING TOO CLOSE yellow warning traffic sign.  Within the context of the study limitations, the study concluded that the traffic sign made no positive impact on the number of traffic crashes.  It was as if the traffic sign was invisible to the motorists.

Assured Clear Distance

According to Ohio Revised Code- Title [45] XLV MOTOR VEHICLES – AERONAUTICS – WATERCRAFT-Chapter 4511: TRAFFIC LAWS – OPERATION OF MOTOR VEHICLES-4511.21 Speed limits – assured clear distance. (A) No person shall operate a motor vehicle, trackless trolley, or streetcar at a speed greater or less than is reasonable or proper, having due regard to the

1. traffic,
2. surface, and
3. width of the street or highway and
4. any other conditions,

and no person shall drive any motor vehicle, trackless trolley, or streetcar in and upon any street or highway at a greater speed than will permit the person to bring it to a stop within the assured clear distance ahead.

A high number of accidents occurred at the two eastbound exit ramps (SOM Center and Harper Road) of US Route 422 in City of Solon.  City of Solon is not authorized to install signs on the US Route.  Hence, City of Solon worked with Ohio Department of Transportation to design a new yellow HIGH CRASH LOCATION-FOLLOWING TOO CLOSE warning sign for the traffic study.  This was a non-conforming traffic sign that was approved by Ohio Department of Transportation for the purpose of the traffic study.  The study ran for 18 months.

non MUTCD compliant traffic sign in Solon Ohio

At the toe of the ramp, some motorists at the rear were looking to the left and moving with less than assured clear distance, before the motorist in the front had moved on, resulting in rear end collissions. The severity of the vehicular damage due to the traffic crashes was not great but City of Solon Police Department staff was being called to the traffic crash location to process the traffic crashes and this took the Police Department’s time away from addressing other higher priority functions.  Traffic congestion on the two lane ramps can lead to very unsafe conditions for the backed up vehicles on eastbound Route 422.

Prior to informational warning signs being posted:

11-17-06 thru 5-17-07

US422 eastbound exit ramp at SOM Center – 19
US422 eastbound exit ramp at Harper Rd. – 14

5-17-07 thru 11-17-07

US422 eastbound exit ramp at SOM Center – 13
US422 eastbound exit ramp at Harper Rd. – 6

11-17-07 thru 5-17-08

US422 eastbound exit ramp at SOM Center – 20
US422 eastbound exit ramp at Harper – 7

After informational warning signs are posted:

5-17-08 thru 11-17-08

US422 eastbound exit ramp at SOM Center – 14
US422 eastbound exit ramp at Harper Rd. – 13

11-17-08 thru 5-17-09

US422 eastbound exit ramp at SOM Center – 14
US422 eastbound exit ramp at Harper Rd. – 5

5-17-09 thru 11-17-09

US422 eastbound exit ramp at SOM Center – 22
US422 eastbound exit ramp at Harper Rd. – 16

The traffic crash data from the informal study obtained from City of Solon Police Department Assistant Chief Raymond Tittl indicates that 52 crashes occurred prior to the posting of the informational warning signs and 50 crashes after.  Ohio Department of Transportation ruled that since the signs were non-conforming they should be removed.  The signs were removed.

I believe the signs were a fine example of cooperation between City of Solon and Ohio Department of Transportation.  The signs performed their function and it was the inattentive motorists that contributed to the disappointing quantitative results.  From a qualitative perspective, the low cost informational warning signs were probably a success and they should not have been removed.  We don’t live in the Garden of Eden; Ohio Department of Transportation’s take on the non-conforming sign is rational.