Answer Man: The whole truth about fractional street numbers

Why do some Rochester streets have fractions? I live on 11 1/2 Street, and it confuses people when I give them directions to my house.

When you live on a 11½ Street, you’re always halfway home.
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Answer Man, I’m hoping you’re an adept aficionado of addresses. Why do some Rochester streets have fractions? I live on 11½ Street, and it confuses people when I give them directions to my house. And if I ever have to enter my address online, the website sometimes gives me an error message. What possessed them to include fractions in street names? — Seth

As always, I will give you the whole truth. If your street address has a fraction, that means you live in an older neighborhood.

"Fractional roadway numbers originated in the earlier days of addressing when a new road was built between two existing roadways," said Randy Growden, Geographic Information Systems Specialist with Olmsted County. "Named roadways were not commonly used at that time, which left them with fractional road names."

For example, if a new road was built between 10th and 11th Street, it became 10½ Street. Or, in your case, your street was built after 11th Street and 12th Street existed.

"As of April 1, 2000, addressing was moved from Rochester Public Works to the Olmsted County Planning Department’s GIS Division," Growden said in an email.


"The use of fractional road designations were no longer implemented, and, as a result, we now have more named roadways. Numbered roadway designations are applied when a new roadway aligns with the E911 Addressing Grid."

E911 stands for Enhanced 911, which is the system used to automatically provide to dispatchers the location of callers 911, the universal emergency telephone number.

Growden and David McCollister are the E911 addressing staff and work for Olmsted County’s Geographic Information Systems Division.

Oh, Grand Poobah of Pavement, show us your street smarts and tell us who’s responsible for maintaining Rochester’s alleys?

Let me set you on the path to enlightenment. That duty falls to the Rochester Public Works Department.

Alleys are maintained by the city, just as its streets are, says Dan Plizga, maintenance supervisor for Public Works.

Of course, alleys are often a conglomerate of concrete, and discerning where public pavement ends and private pavement begins can prove difficult. Property owners are responsible for any pavement off the right-of-way.

Plizga said Rochester’s alleys aren’t getting the attention they deserve.


"They just haven’t been a maintenance priority," he said. "People should talk to their council person about additional funding."

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