The state D-O-T is renewing its warning to Iowa motorists to keep an eye out for road maintenance workers — especially at night. Interstate repair projects are underway in Des Moines, Council Bluffs, Bettendorf and between Cedar Rapids and Iowa City — all between the hours of 8 p-m and 6 a-m. D-O-T traffic safety engineer Mark Bortle says the vampire hours work best for some road work jobs as there is less traffic and they don’t have to slow motorists on the way to work.Bortle says there have been no road work zone deaths statewide this year, but last year there were six people killed — all of them motorists. He says historically 85-percent of the work zone fatalities in Iowa are motorists. Bortle urges drivers to use extra caution and slow down as they approach a night work zone. He says drivers are sometimes blinded by the overhead lights used in the work zones which, if you’re not paying attention, can pop up unexpectedly.