After coming to a complete stop behind a crosswalk or stop line painted on the street, motorists in Minnesota can make a right turn on a red light unless signs posted at the intersection prohibit the maneuver.

The law also requires drivers to yield the right of way to pedestrians and bicyclists before making a right turn on red, and to use caution while doing so.

That is all clear to Drive reader Bill Lynch, but he wanted to know why that message is conveyed several different ways in Minneapolis.

Right turns on red lights are not allowed at the intersection of W. Broadway and N. Penn Avenue in north Minneapolis. Motorists heading north on W. Broadway see a white sign with the words "No Turn on Red" in black letters. Motorists heading south on W. Broadway see a white sign with black letters reading "No Turn on Red" and a red dot below.

In other places, signs feature a red dot in the middle of the words "No Turn on Red." And in rare occurrences, such as at the intersection of W. 15th and Willow streets near Loring Park, one sign features a green arrow and says "Right on Green Only."

"Why are there multiple signs saying essentially the same thing?" Lynch asked the Drive in an e-mail. "Why do some have red symbols while others do not? I find it intentionally confusing."

The Drive took the question to the Minneapolis Public Works Department, which sorted it all out.

The city of Minneapolis has more than 400 "No Turn on Red" signs, some of which date back many years.

Over time, city, state and federal regulations for the signs have changed.

"Because of this, you may have signs that convey the same message but look different," said city spokeswoman Sarah McKenzie. " 'No Turn on Red' signs are an example of this."

Current city standards that meet state and federal regulations for "No Turn on Red" signs call for the red dot to be placed below the words, McKenzie said.

The older signs with the red dot in the middle of the "No Turn on Red" and signs that have the "No Turn on Red" without a dot still meet state and federal standards, McKenzie said.

Minneapolis has more than 115,000 traffic signs throughout the city, and it's a big job to take care of them.

Over the next five years, the city will replace the older yet compliant "No Turn on Red" signs with those that meet current city, state and federal standards with the red dot at the bottom of the sign.

As for the "Right Turn on Green Only" signs, they are posted at a few intersections with unusual stoplight configurations. McKenzie said they are rare.

For instance, where Willow Street ends in a "T" intersection with 15th Street, the stoplight allows right turns from southbound Willow onto westbound 15th at the same time eastbound drivers on 15th can continue straight or turn left onto Willow.

Westbound 15th Street drivers need to stop while all that's happening because permitting another traffic movement during that signal phase could prove dangerous.

Thus the "Right Turn on Green Only" tells westbound drivers on 15th to stop at the red light and not turn right until they see green.

"That is a separate message from the 'No Turn on Red,' " Mc­Kenzie said.

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