A challenging winter for Ames street crews

The man responsible for clearing snow from 600 miles of Ames streets says this winter's been especially challenging.  Public Works Operations Manager Justin Clausen says snow combined with bitterly cold temperatures meant street crews had to use alternate methods to control ice--switching from sodium chloride, which works only to temperatures at 10 above zero, to calcium chloride, which is effective at 30- to 40-below.  He says road salt and calcium chloride are hard on machinary and new pavement.  Clausen says crews have had to clear 15 inches of snow from Ames streets so far this winter.