What Is a Road/Stream Crossing Inventory?

Thanksgiving break as a kid was spent with my grandparents, who lived on a block of identical brick houses in a suburb of Detroit. The highlight was a trip to Toys “R” Us — a mind-blowing metropolis of playthings for a country kid — to pick out my own birthday present.

I had an hour to scour the store and take inventory of what I could buy with the birthday cash crammed in my pocket. RC cars were too pricey. Board games were affordable but they weren’t toys. I usually landed in the Lego aisle because I could build the set then combine the pieces with my existing collection back home. On top of that, my grandpa — a retired pipe fitter for a steel mill — was liable to kick in a few extra bucks toward a practical choice like Legos.

This is a bit like how our river restoration work is done at Huron Pines. With only so much money in our pocket in a given year, we need to know where those dollars can make the biggest impact. The new bridges and culverts we install on streams across Northern Michigan are the result of years of planning and prioritizing where our efforts will do the most good, all of which is built on the foundation of a road/stream crossing inventory.

Josh Leisen is Senior Project Manager at Huron Pines whose job it is to find and fix crossings that are causing issues like erosion, flooding or preventing the movement of fish. Most problems come from culverts that are too small for the river to flow naturally through the crossing.

“We’ve learned, since those culverts were put in decades ago, that a majority of them were done  without an awareness of how the stream would change,” he said. “Now we know the negative effects of undersized culverts and can install new ones that are better for the watershed.”

A watershed is all the land and water that drains to a single outlet. For example, the Thunder Bay River Watershed is everything that empties into Thunder Bay, and the Lake Huron Watershed includes all the parts of Michigan and Ontario that drain into Lake Huron.

To restore a river, we first need to know where the issues lie. Our work starts by documenting each crossing within a watershed. We use a protocol Huron Pines developed alongside other natural-resource partners to gather data in a uniform way.

Josh Leisen uses a flow probe to measure the velocity of a stream at a road crossing. This data will be compared to that taken at a free-flowing location to determine how much of an effect the crossing has on the river.

“This is done so we can compare apples to apples across the entire Great Lakes region,” Leisen said. “We can use the same process in Minnesota as in Michigan.”

Armed with the tools of his trade, Leisen hikes up his waders and steps into the river to assess the structure and record river conditions upstream and downstream of the crossing. He also gauges the river velocity at a nearby location that he feels is representative of the stream’s natural state.

A watershed inventory can take a year to finish. After that, crossings are prioritized based on the severity of problems, the potential for reconnecting river miles, proximity to other projects, and the availability of partners who see the value of our work and want to help — just like the way my grandpa chipped in for Legos.

One of Leisen’s earliest projects was an inventory of the Rifle River Watershed near Saginaw Bay, which led to a dozen structures being replaced between 2013 and 2018. A big part of that effort involved partners like the Rifle River Restoration Committee, Saginaw Bay Watershed Initiative Network, two Trout Unlimited chapters, area businesses, local governments and road commissions who helped fund those restorations.

Leisen revisited the watershed in 2019 for a post-restoration survey using the same methods as before for an apples-to-apples comparison.

Timber Bridge
Before and after: The crossing of Gilchrist Creek at Harwood Road in southeast Montmorency County, where three undersized culverts were replaced with a timber bridge in 2020.

“The data verified the river has improved quite a bit,” he said. “We didn’t find any significant issues which is what we expected but it’s always good to see that in the field.”

This year, Huron Pines is undertaking an inventory on the grounds of Camp Grayling. At 147,000 acres, the nation’s largest National Guard training facility hosts exercises for all branches of the military and is also home to 312 miles of the Au Sable and Manistee rivers.

Natural Resources Specialist Matt Kleitch is a civilian in the camp’s environmental office whose job is to ensure Camp Grayling complies with regulations related to natural resources management and permitting, among other environmental issues.

“The idea is to do a total inventory of existing stream and wetland crossings, to document what condition they’re in and, ultimately, to prioritize what crossings are in the most need of improvement,” he said of this year’s inventory, which will begin with computer work using geographic data. “That information will plan the field work, with folks going to those sites to do qualitative and quantitative data collection.”

Once complete, the inventory will be used to inform future restoration projects on Camp Grayling’s portions of the Au Sable and Manistee river watersheds, two premier trout streams of the Midwest. Kleitch said restoration money could come from federal programs intended for the benefit of threatened plants and animals — the camp is home to 18 such species including the Eastern massasauga rattlesnake.

“It’s not uncommon for military installations to be hotspots for biodiversity,” Kleitch said. “It’s a lot of undeveloped land that’s intentionally managed in a sustainable way, so it ends up holding diverse species and Camp Grayling is no exception.”

Ultimately, our inventories are a chance for us to put on our waders and get our hands dirty — and that’s an opportunity we never pass up.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.