Readers Respond

Monday, March 14, 2005

Keep speed limits where they are

To The Editor:

Some top Iowa legislators are eager to increase the speed limit and fatality rate. Tell your lawmakers that Iowa doesn't have to follow the herd instinct and run off the cliff with the heavy foot states. There's more than enough proof that past speed limit increases immediately increased the fatality rate per 100 million vehicle miles of travel on those same highways, but the leadfoot lobby cleverly mixes those increased fatality rates on increased speed limit highways in with the "total" or "national rates", because the latter has declined in recent years because of better drunk driving laws, more air bags, and better teen age licensing. The general public doesn't know what increased speed limits and increased speeds have done unless they "select out" and study the highways where speed limits were increased instead of just looking at "total numbers".

The fatality rate on Iowa "expressways" (non-interstate divided) was 0.39 per 100 million vehicle miles during 1993-95 while at 55 mph, but jumped to 2.33 within one year after 65 mph. A lesser increase happened on Iowa interstates immediately after 65 mph came onto them in 1987, and the "rates" on neither went back down to pre-65 mph levels.

Check into http://www.dot.state.ia.us/speed2002.htm. Ask for table 8 and 9 crash and injury rate comparison on Iowa Expressways. Also check www.highwaysafety.org. Status Report 22 Nov. 03, and 12 Jan 99 for the increased fatality rates on US Highways where speed limits were increased.

We know the motoring public always "exceed" the posted limits by however much law enforcement tolerance allows. Boosting the speed limit will boost the "actual speed" by the same amount and increase fatality rates within a short time. Those increases spill over into adverse driving conditions. Ask the heavy foot lobby if we need some more of those multi-vehicle pile-ups in the fog or ice.

- Herman Lenz, Sumner