“The benefit valuation is the financial savings of fewer crashes compared to the cost of revision,” Ostendorf said. “Typically we look for a 1.5 to a 1.8 ratio as being a quality benefit cost. This intersection surpassed that quite a bit.”
According to Ostendorf, the intersection graded at 1.97, well above what the department looks for when designating TSIP funds. With 27 accidents from 2004-2008 (and more following), it ranked as the city’s 23rd most hazardous roadway during the time of the study, and has likely moved up since Clinton has amended some of its more pressing road hazards.
Back then, it had the eighth most accidents of any city roadway (no fatalities, one minor injury). According to the DOT, almost all of these collisions were “intersection-related” accidents.
-This GoogleMap illustrates the frequency of crashes from 2004-2008.
“Very rarely do we have benefit costs that high,” Ostendorf said. “The benefit cost was such that it was a strong candidate through the review committees. It was deemed to be a quality project.”
Craft’s department drafted the proposal and calculated the benefit cost ratio. He said the intersection would have seen revision even without help from the DOT, especially with looming construction of a new middle school in the area.
“Since we’ve got the funding, we will move forward on planning in this next year,” Craft said.
TSIP is a decades-old state program enacted by the Iowa Legislature. It skims 1 percent off road tax revenues for specific project requests. The highest funding rewarded this year was $500,000 for eight projects in the cities of Iowa City, Des Moines, Ankeny, Carroll as well as Montgomery, Lee and Clay counties.
The money awarded this year will come out of TSIP’s FY 2015 budget.