The push to raise $100 million or so from public and private sources to turn Central Iowa’s riverfronts into one big adventure park comes as the metro area faces many other financial challenges, from mass transit to affordable housing to taking care of streets and sewers.

But backers of the so-called water trails system — which would plop whitewater courses, zip lining and surfing on downtown Des Moines’ two rivers — say the work is doable. With the option to stage the work and the financial wild cards of having two local sales taxes pending approval, leaders of the Greater Des Moines Partnership, the Community Foundation of Greater Des Moines, the Des Moines Area Metropolitan Planning Organization and key businesses say they are confident the decadelong effort will succeed. 

It must, in the view of Partnership CEO Jay Byers and Hubbell Realty Co. President and CEO Rick Tollakson. 

“This project is the most transformational quality of life project of our generation, and we need to get it done,” Byers said in an interview. “We still haven’t activated the river. These low-head dams are death traps. You can’t get on there.”

The project would improve recreation around the area, but a $35 million reworking of the Center Street dam area would help create a centerpiece: an adventure park at the river that would include a separate zip line development and the next-door Lauridsen Skatepark. 

In a separate interview, Tollakson said the project will ramp up the momentum that recreation trails, the microbrew scene, music and arts offerings, and the planned skate park have established. 

“Businesses care all about workforce attraction,” Tollakson said. “We have to do something. We don’t have any workers.”

Tollakson is confident the money will be raised, and has been in the middle of making sure it does. The idea is to bring in two-thirds of the budget from local, state and federal sources, and one-third from local private interests.

“This is a big ask for the state,” said Tollakson, who regularly bends the ear of his state senator, Charles Schneider of West Des Moines. “(But) there is a lot of interest in getting this funded.”

Todd Ashby, executive director of the Des Moines Area Metropolitan Planning Organization, also is optimistic. “We definitely think it’s doable,” said Ashby. The MPO has led the study of revving up river recreation in the area, under contract with the Iowa Department of Natural Resources.

An engineering study by ISG, McLaughlin Whitewater, RDG Planning & Design and HDR found the range of costs for the area would be $98.6 million to $117.1 million. The work could be staged.

The downtown project calls for $76 million of work in the rivers, including the installation of four sets of rapids in the Des Moines River near the Center Street dam, with $11.6 million to $30.1 million in work along the banks to make the river more usable. Those figures don’t include planned fundraising for an endowment to pay for maintenance.

The price tag puts the project in range of a few other large ones in recent decades. The Principal Riverwalk eventually added up to $72 million and is still spawning spinoffs. Wells Fargo Arena cost $99 million, and the Hilton Des Moines Downtown, $101 million. 

Capital Crossroads tri-chairs Byers, Kristi Knous, president of the Community Foundation, and Polk County Supervisor Angela Connolly are leading the feasibility work on the projects. The funding feasibility study is supported by the Greater Des Moines Partnership, Community Foundation of Greater Des Moines, Greater Des Moines Committee, Greater Des Moines Convention and Visitors Bureau, Des Moines Area Metropolitan Planning Organization and Hubbell Realty Co. 

The first mission: Explain the project and get people excited about it, supporters said. 

“It’s early in the process,” Knous said. “We need to go out and test the concept. We need to get these numbers out there to prospective major contributors — businesses and individuals. We need to build momentum and excitement and tell the story. ‘Who are the partners who will step up and make this possible financially?’ ”

Hannah Inman, executive director of Great Outdoors Foundation and coordinator of the fundraising, has started the one-on-one interviews with prospective donors to gauge support. At roughly the same time, supporters will come up with an economic impact report on the project.

The Des Moines City Council discussed the project at a work session Monday morning that served as the unveiling for the engineering study.

West Des Moines and Johnston already are moving on elements of making rivers and creeks more usable. On the other hand, Des Moines City Manager Scott Sanders said in an interview months ago he sees the value in the water trails in workforce development, but a $75 million backlog of work on streets, sewers and other infrastructure would make it difficult for the city to spend on water trails. 

“It needs to be at the right time looking at the payment,” Sanders said. “There’s a time and place for that type of an expense is all I’m going to say.”

Even then, Sanders can see the value of the projects. “Quality of life is important. And so is diversity in recreational opportunities. We don’t have mountains and oceans, but we do have a river feature. The riverwalk has shown that there’s a lot of interest and pride in that asset.”

MPO spokesman Gunnar Olson said the various proposals along 150 miles of streams in the area would provide fun spots for people of all skills — from rafting and swimming to fishing  to kayaking whitewater. 

And that vision came from a broad-based coalition. “The network cannot be overemphasized,” Olson said. 

“It is very important that what is built downtown is compatible with the other projects” such as the Principal Riverwalk and the planned Lauridsen Skatepark near the Women of Achievement Bridge, he added. 

The engineering study that led to the report was supported by the Leadership Circle of the Greater Des Moines Community Foundation, local cities and counties, Catch Des Moines, the Partnership, Polk County Conservation and the Des Moines Area Association of Realtors.

Byers said programs in the state and federal government that pay for dam safety, water quality and ready work could help pay some of those costs. As far as the city of Des Moines’ involvement, he said, “It’s very early in the process. The important thing is to get the project moving forward and to acknowledge that it’s a multiyear project. The city does have many needs.”

“The local option tax would help,” Byers said of a local sales tax for property tax relief, public safety and neighborhood projects that could return to the ballot as early as March. 

Knous has heard directly from residents, especially younger ones, who love the idea of a downtown adventure park. “Young people get so excited. This gets feet into the water. This will be a draw to the riverwalk to watch and get excited.”

The price tag is large but so is the need, Byers and other backers say. Work now will turn to a funding feasibility analysis, and making the case for the project as an economic development drive.

A big wild card: Possible legislative approval next year or later of a proposed local sales tax to pay for outdoor recreation and conservation projects, to the tune of $180 million a year. And that tax, envisioned by voters who overwhelming approved a state trust fund for the purpose in 2010, would mean visitors to the area would help pay the cost, said Inman, who is coordinating the fundraising.

Tollakson said the festivals, craft beer, recreation trails, music and art offerings, and other attractions help. The water trails, which he saw firsthand in trips to Boise, Idaho, and Columbus, Ga., can be another big draw that will help coax people to use the rivers.

Leaders in Waterloo, Fort Dodge and Iowa City have discussed adding the attractions. Manchester, Elkader and Charles City already have them. 

Walnut Creek, Walker Johnston Park, Urbandale