Plans to provide better access and more recreational opportunities on the Des Moines and Raccoon rivers in downtown Des Moines are coming into focus.

A Colorado engineering firm has outlined how Des Moines can revitalize the rivers at three key points: the Center Street, Scott Street and Fleur Drive dams.

The Des Moines Metropolitan Planning Organization is leading a coalition of groups that wants to mitigate the low-head dams, dubbed by some as “drowning machines,” that limit access to large stretches of the rivers.

The dams likely won't be removed entirely since they help regulate water levels upriver, but engineers say they can make them safe for kayaks and other watercraft by installing ramps and other measures.

That creates "additional flat water opportunities, habitat, fish passage, all kinds of good things," said Pat Boddy from RDG Planning and Design, one of the firms that working on an engineering study.

These three strategies were developed by McLaughlin Whitewater Design Group and presented at the Dam Debate III open house Thursday at The Des Moines Register Community Room:

Center Street dam

The Center Street dam's 7-foot drop is the best opportunity for high-energy water activity, like whitewater kayaking or surfing.

Officials from Des Moines have toured whitewater river amenities in Boise, Idaho, and Chattanooga, Tennessee, that have become significant tourism draws.

Engineers would use ramps to make the dam safe for recreation and install mechanical flash boards to regulate upriver water levels and adjust the "wave" used by kayakers or surfers.

The site would remain unusable to canoes and motorboats because of the large drop, but the McLaughlin Group estimates it could serve kayakers and surfers from May through September.

The dam sits just north of the Iowa Women of Achievement Bridge and is one of the city's deadliest.

It's the site of an infamous river rescue in 2009 when construction worker Jason Oglesbee dropped from the bridge to save a woman stuck in the rolling water.

Scott Avenue dam

Scott Avenue dam, at the confluence of the Des Moines and Raccoon rivers, would best serve flat water paddlers and intermediate whitewater activities, the engineers report.

It's really about recreation for all, Boddy said.

Engineers say fishing, swimming, wading, canoeing, kayaking, tubing and nature hiking are all possibilities. This site shows the most potential for habitat restoration for fish and other wildlife.

Andy McCoy, a water resources engineer with HDR, said Thursday that Iowa Department of Natural Resources' studies have shown the Scott Avenue dam prevents catfish migration. These fish can migrate up to 300 miles, he said.

Fleur Drive dam

The Fleur Drive dam on the Raccoon River just north of West Martin Luther King Jr. Parkway could be repurposed similar to Scott Avenue, but tailored to serve all ages.

It's the closest to Gray's Lake which means beginning paddlers could portage there to practice whitewater skills before testing them on the Des Moines River rapids.

Water quality

Whether people want to get into the Des Moines River is a top concern for many.

"Being a lifelong resident of Des Moines, I was taught you can't get into the river, that you'll die if you do," Councilman Joe Gatto said Thursday.

Des Moines and Raccoon rivers are listed on the state's impaired waters list. The Des Moines River especially suffers from spikes in bacteria, a long running problem for the river, said Chuck Gipp, director of the Iowa Department of Natural Resources.

"We’re not going to minimize water quality issues in Iowa ... but if you put your big toe in the river at this point you don’t have to run home saying, I'm going to die," Gipp said.

"It is safe to recreate on this particular facility but that doesn't mean we as a community don't have to do more for water quality," he said.