ENFORCE MINIMUM SPEED LIMITS TO REDUCE CAR CRASHES AND IMPROVE THE FLOW OF TRAFFIC

Enforcement of minimum speed limits would be more effective at preventing accidents than enforcement of maximum speed limits

By Jay Wall

Big Jolly Politics
November 18, 2016

Car crashes in Houston increased 67% from 2011 to 2015, more than 26,000 crashes a year. Traffic delays have increased along with the rise in accidents. The delays have very real costs – 61 hours in delays, $1,490 in lost time, and 29 gallons of wasted fuel per auto per year, according to the Texas A&M Transportation Institute. What’s the solution? The City of Houston has severe financial problems, so new roads, miles of trains, and other budget busters are not a realistic option. Realistic solutions should take advantage of the 80/20 rule to create efficient, budget friendly solutions.

Italian economist Vilfredo Pareto, noted, among other things, that 20% of the peapods in his garden produced 80% of the peas. In business, it’s often heard that 20% of the salespeople produce 80% of the sales or 80% of the business comes from 20% of the clients. In Houston, 80% of the traffic problems come from 20% of the drivers – and we all know exactly who they are. The driver doing 15 miles an hour below the flow of traffic in a freeway passing lane; the driver lane jumping at an entrance ramp and coming to a complete stop to enter the ramp; and the slow driver who shouldn’t be on a freeway at all. Solving these three problems is not a budget buster. It may be a revenue enhancer.

One major factor in the rise in traffic accidents has been that even as more people have moved into Houston, the Houston Police Department has backed off traffic enforcement. In the same period from 2011 to 2015 while traffic accidents spiked 67%, traffic citations dropped 31%.

Obviously that drop wasn’t due to Houstonians becoming better drivers. While ticket revenue shouldn’t be a budget balancer, increased enforcement with increased fines is definitely not a budget buster.

Enforcement of minimum speed limits would be more effective at preventing accidents than increased enforcement of maximum speed limits, while also improving the flow of traffic.

Traffic moving 5 to 10 mph below the posted speed limit is more likely to cause an accident than traffic moving 5 to 10 mph above the posted speed limit. Traffic moving 15 mph below the posted speed limit (a typical minimum speed limit level) is approximately twice as likely to cause an accident as traffic moving 15 mph above the limit.

Lack of lane discipline makes the issue of dangerously slow drivers even worse. In a paper presented at the 50th annual Transportation Research Forum, Reinhard Clever, Ph.D. noted that cars being forced to zigzag around slower moving vehicles “almost equally distributed over all freeway lanes” may be the leading factor in rising fatality rates as speed limits are raised on freeways. A study in Michigan from 2007 found that posting “Keep Right Pass Left” signs did not affect driver behavior without enforcement. For a “keep right except to pass” policy to be effective, the public has to believe it will be enforced.

Anyone who has driven more than 10 miles on a Houston freeway during the workday has seen the lane jumpers, drivers who pass a long line of cars in the exit lane, come to a complete stop in the driving lane and muscle their way onto the exit. The stretch from Gulfon/Fournace road on the West Loop, north to the SW Freeway, is one such stretch. Another is the junction of 59 North and I-45 South. Name a freeway interchange in Houston and there is probably a similar situation. The HPD could enforce existing solid white lines at less than zero cost. Particular problem areas could be enhanced with longer lane change prohibitions.

The Texas A&M Transportation Institute’s Mobility Scorecard noted that “Getting more productivity out of the existing road and public transportation systems is vital to reducing congestion and improving travel time reliability.” This is never more true than today in a financially strapped, traffic weary Houston. I’ve suggested a few possible solutions and there are likely other improvements to be made. The common theme is targeting the 20% of drivers that cause 80% of the problems and aggressively enforcing the rules that slow traffic, causing accidents.