Gravel biking has taken over the Midwest — and Iowa is destined to be one of cyclists' top destinations.

• Just look at RAGBRAI. Today marks the ride's Gravel Day, and this year, planners expanded the route to include roughly 50 miles of unpaved roads.

Why it matters: Cementing our superiority in the growing sport can draw tourism, more rides and races, and big names in the future.

But, what is it exactly? Cyclists use bikes with larger frames and tire widths to handle unpaved terrain.

State of play: Local shops can barely keep gravel bikes in stock. And there are a few reasons why Iowa is poised to be a hot spot for the fastest-growing sector in cycling, according to Cole Ledbetter, founder of online gravel cycling community Iowa Gravel Project.

• More than 50% of Iowa roads (roughly 67,000 miles) are made up of gravel, and they're better maintained than other states' because farmers use them year-round.
• Iowa has every type of terrain. Go to the southwest corner of the state and conquer monster hills, or head north of Ankeny and it's as flat as the eye can see.
• Plus: How can you get lost when it's all a grid?

What to watch: Our scene is growing and you can find a race or ride every weekend during competition season.

• Although most of the events are homegrown, expect to see big races someday like The Mid South or Unbound, Ledbetter said.

Ledbetter and his fiancee, Kelsi Jurik, are tying the knot in Alden today at the end of RAGBRAI's Gravel Day.

• They're mixing together gravel from the roads they grew up next to into a beer stein. And that, my friends, is romance.

The bottom line: People feel passionate about gravel.

It's time to get out and smell the wildflowers.

Driving the news: DSM has added about 200 acres of prairie grasses and flowers throughout its park system over the last 13 years. Much of it is in full bloom right now.

Why it matters: It's pretty, and it helps the environment. Roots from some of the plants can run more than 15 feet deep, reducing erosion and the severity of floods.

• Plus: It saves big bucks.

The intrigue: The initial prairie projects were launched to save money during a city budget crunch in 2008, DSM parks director Ben Page told us.

• They weren't popular at first because the plantings weren't aesthetically pleasing. (Hey, if you've gardened, you know the first tries can flop.)
• Research and planning improved to include seeding that has color.

Of note: The parks department doesn't track the financial savings attributed to prairies.

• Yes, but: It costs about $30 an acre to mow and there are generally more than 20 mows in a year, DSM Parks director Ben Page told Jason. ($30 X 200 X 20 = $120K)

The bottom line: The real savings come in flood reduction.

• Each acre of prairie can absorb nine inches of rain an hour, according to the Dickinson County Conservation Board.

We told you last week about a regional utility in DSM, and how the gas it created during wastewater treatment is now being captured and sold to the tune of $5 million a year.

• Des Moines Metropolitan Wastewater Reclamation Authority (WRA) is offsetting expenses and paying debt with the proceeds.

Question: Axios reader Kent Balduchi of DSM asked us, could the same technology be employed to extract valuable products from concentrated animal feeding operations (CAFOs)?

• If so, it would offset the cost of disposal to producers and could possibly become an additional source of revenue.

Answer: Yes, it's possible. But most facilities are not large enough to be cost-effective, WRA director Scott Hutchens told Jason this week.

• CAFOs would need to capture the raw biogas through a wastewater treatment process and then clean the gas before it could be pipeline quality.
• WRA invested $20 million to handle its process.

The big picture: Animal manure in the U.S. has the equivalent energy content of billions of gallons of diesel each year, according to a 2019 National Renewable Energy Laboratory report.

• It holds great promise in reducing environmental impacts of livestock agriculture, but the technology is rarely profitable without government support, according to a report last year from Yale Law School.

🙊 Our thought bubble: There's lots of untapped poo-tential, here.

🏈 The Big 12's future is in doubt after Texas and Oklahoma took the first steps to leave. (Des Moines Register)

🗳 AFSCME's longtime leader Danny Homan has retired. Members of the state's largest public workers union elected Rick Eilander, a former jailer with the Jasper County Sheriffs’ Office, as president. (Cedar Rapids Gazette)

🌳 Johnston's new City Hall was built using wood from trees that previously stood at the site. (Business Record)

Blank Park Zoo added this fella to its exhibits last week.

• Romakari is an okapi, an endangered animal that's native to the Democratic Republic of Congo.