The Mystery of Why Mobile Speeds in Denver Are So Terrible

Denver has a reputation as one of the more technologically advanced cities in the country — yet, as we've reported, our cell-phone service has a national reputation for sucking.

And two new reports reinforce it.

According to data from the websites RootMetrics and Ookla, Denver's mobile speeds are among the worst in the United States. The woeful numbers and rankings are on view below in all their hideous glory.

But that leaves the question of why Denver has such persistent mobile speed issues — and according to Annette Hamilton, RootMetrics' director of influencer and analyst engagement, there's no definitive answer.

"We don't know exactly why the mobile performance in Denver is historically not good, relatively speaking, compared to the rest of the U.S.," Hamilton acknowledges. "But we have some theories."

Among them is the mountainous terrain in the area.

"We do know that other Rocky Mountain cities do seem to have similar problems," she notes. "That suggests a geographical issue" — and indeed, Colorado Springs does almost as badly in RootMetrics' most recent mobile-speed survey as Denver.

As we've reported, the mountains and foothills play havoc with Denver radio signals, particularly on the FM band. Moreover, Hamilton says, "mobile phones use the radio spectrum — and when I talk about how the different spectrums can impact performance, I often use the analogy of AM and FM radio waves."

One of the main spectrums used by mobile networks "is called the 700 megahertz spectrum," she says. "It's more like AM. It's a slow, sort of long-range radio wave that goes a long distance, but it's not very fast. And then another spectrum that some carriers use — T-Mobile has deployed it in some markets — is the 2.5 gigahertz spectrum. It's very short-wave and goes faster, but it's not going to go through buildings or mountains or around corners. It's more like an FM signal and pretty much line-of-sight."

Hamilton says mobile-phone service providers have been doing their best to overcome these issues. "LTE, which is responsible for 4G mobile coverage, is pretty well saturated in the Denver area," she emphasizes. "That suggests the carriers have invested heavily in the latest and greatest technologies in the Denver area, and it still hasn't made that much of a difference. Maybe a new technology will come along and solve these problems we're facing in Denver, but we don't know what that would be or when it might happen."

Another possible factor when it comes to lagging mobile speeds "has to do with the population explosion you're experiencing," Hamilton adds. "You guys are growing like crazy, and the more people you get on a mobile network, the more stress it puts on that network — and the less well that network is likely to perform. So it could be a combination of geography challenges and population. But we still can't pinpoint what's going on."

That's not especially reassuring to those of us who chronically experience dropped calls, terrible connections and more.

Continue to see Denver's terrible mobile speeds performance in two photo-illustrated reports.