iPhone mounted on bike handlebars
October 10, 2016

Assessing the condition of Minnesota’s trails, one mile at a time

Have you ever been riding along one of Minnesota’s beautiful bicycle trails when, thud, a jarring bump shakes your entire frame? Well, you’re not alone. Staff, board members and volunteers from Parks & Trails Council have been spending the summer out on the trails, feeling—and recording—these bumps ourselves.

As Minnesota’s bicycle trails age, trail maintenance has become a hot-button issue at the legislature. So much so that perhaps no other issue is more important to the long-term viability of Minnesota’s bicycle trails.

To begin addressing this challenge, our latest research project is assessing the condition of every mile of trail pavement in Minnesota’s State Trail System. Our assessment will provide managers, policy-makers, and trail users with a detailed, mile-by-mile snapshot of trail conditions across the entire state. This will be the first time such information is publicly available, and will be vital for understanding how much work is needed to get all of Minnesota’s trails in good shape.

We’re collecting three types of information: First, we’re taking the “old fashioned” approach of giving every mile a subjective rating between poor and excellent based on our experience from riding it. Second, we’re taking photos. And third, we’ve mounted iPhones on our bicycle handlebars to collect data on the force of vibration caused by bumps and depressions on the trail.

To our knowledge, this research is the first large-scale, system-wide effort using smartphones to collect objective data on trail pavement conditions.
Data collection started over the summer and is planned to go through October. To date, we’ve completed 430 miles of the roughly 600 miles in the state system. That amounts to over 1,200 photographs and over 330,000 data points logged on our iPhones.

In the coming month, we’ll crunch these numbers and pinpoint the locations in most need of repair. This data will also provide an overview of the system as a whole to help guide the development of trail maintenance plans.

Be on the lookout for our final report, which we expect to release in December.

How can iPhones collect data on trail conditions?

Did you know that all you need to turn your bicycle into a data-collection machine is a handlebar mount for your iPhone? All iPhones come equipped with a handy device called an accelerometer, which is designed to measure vibrations. Once your phone is configured to record this data, every ride becomes an opportunity to collect valuable data.

Comparison of smooth pavement vibrations with pavement in disrepair