What’s the Deal with the Fraction Streets in Grand Junction?

Having been in town less than two weeks, I've not made it around much except, from the Double Tree to work, and a couple trips downtown. Today I was rolling down North Avenue when I spotted it. A "fraction" street number. I can't say I've never seen the  phenomenon, I have. Mostly in larger, more densely populated, cities back east, but here in Grand Junction? My question is why? 

Each town I've worked in has its own weirdness. That's part of the fun part of living in various markets over the past several years. Springfield, Mo. is weird because they have no numbered streets. St. Louis and Kansas City each do, but one is numbered north and south the other east and west. Which is right? Depends on what city you're from.

But here, why? Then I saw it a 1/4 street sign!  What? You've got to be kidding me! There seem plenty of room for regular number streets? What's the need for a "1/2" street let alone a "1/4." This is weird and I've got to know. What's the heck's up with the Grand Junction "fraction" streets?