The use of road markings and paints in the United States simply started with milk. In 1911, the first documented use of a road center line was painted along the Trenton’s River Road in Wayne County, Michigan. The idea was first conceived by a man named Edward N. Hines, who was the chairman of the Board of Roads of Wayne County at that time.
Hines once watched a milk wagon pass by and saw that the leaking milk from the wagon created a white trail along the road. This gave him the idea that the color of white can be painted along the road to create a visible center line. The initiation of his idea became a founding record of the use of safety road markings and Hines was posthumously inducted into the Michigan Transportation Hall of Honor in 1972.
Around 1917, the use of road paint to create center lines along rural state highways was independently initiated in the states of Michigan, Oregon, and California. Under the initiation and direction of Kenneth Ingalls Sawyer, who was the engineer-superintendent of the Road Commission of Marquette County, a white center line was painted along the “Dead Man’s Curve.”
Now called County Road 492 in Marquette County, Michigan, the Dead Man’s Curve was a horse-shoe shaped road that was famous for the numerous traffic crashes that occurred on that road and produced high traffic mortality. Sawyer was also inducted posthumously into the Michigan Transportation Hall of Honor in 1973.
Also in 1917, a yellow paint was used as a center line along the Columbia River Highway in Oregon under the direction of Peter Rexford, who was the Sheriff’s Deputy in Multnomah County at that time. The idea was conceived while Rexford was riding a bus on a dark and rainy night, when he travelled from Salem, Oregon.
The yellow center line was first advocated as a road safety measure on the Columbia Civer Highway; however, the funding of project was turned down by the Multnomah County. Martin T. Pratt, who was Rexford’s boss and Chief Deputy, believed in his advocacy and decided to fund the project for him out of his own pocket.
The yellow center line painted on the Columbia River Highway in April 1917 was probably the first yellow road paint to be used on pavement in the United States.
“The Doctor June McCarroll Memorial Freeway,” which is a portion of the Interstate 10, was designated and signed in 2002 in honor of Dr. June McCarroll of Indio, California. She started advocating the use of white center lines on highways in the fall of 1917, after personally experiencing a traffic accident where she was run off the road by a truck while driving.
Her advocacy for the project funding was unfortunately turned down by the local chamber of commerce and the Riverside County Board of Supervisors, so she decided to hand-paint the center lines herself. The white stripe she painted in the middle of the road established the width of the lane to prevent accidents similar to what she experienced.
The use of a standard road paint color for highway center lines in the United States was widely debated for a long time and the standards were changed over several decades. 47 states adopted the color white as the standard for their highway centerlines by November 1954, leaving Oregon as the only state to use yellow. By 1958, white road paint was adopted as the standard for the interstate highway system by the U.S. Bureau of Public Roads.
Then, in the 1971 edition of the Manual on Uniform Traffic Control Devices, the yellow road paint was mandated as the standard for centerlines nationwide. The color yellow was adopted because it was the standard color of every known warning signs.
Yellow road paint was also easy for drivers to associate with dividing opposing traffic while white was associated with dividing parallel traffic, thus reducing the number of head-on collisions and improving road traffic safety.