From the Michigan Observer & Eccentric "It was a long cooperative road to getting around" by Ruth Moehlman.
Edward Hines, a Wayne County commissioner is given credit for his 1911 invention of what is considered by many to be one of the most important developments in automobile safety, the white line in the center of the road.
He claims that an accident between an automobile and a horse-drawn wagon carrying milk inspired his idea when the milk leaked out on the road.
In other road history, in 1909, the Wayne County Road Commissioners oversaw the construction of the first concrete road, one mile long between Six Mile and Seven Mile roads on Woodward Avenue.
Mr. Hines died in 1938 and today's Edward Hines Park and Edward Hines Drive are named after him.
So, That's the Reason. --RoadDog