Dam Mitigation

Take a look at our 2020 low-head dam mitigation map and check out the actual projects completed or underway:


Buffalo Creek Dam Removal and Rapids Construction

Completion Date: January 2018
$370,060 in dam mitigation grants and technical assistance

Linn County Conservation decided to remove the dam at Coggon after sedimentation had significantly reduced the upstream impoundment and evidence showed that declining mussel populations could rebound if the stream were reconnected. The dam was reduced in stages over two years to reduce impacts of sediment movement. A small, fish-passable rapids was constructed to stabilize the area.


Coggen Before Photo
before removal

Coggen After Removal
after removal


Mason City Willow Creek Dam No. 3 Removal

Completion Date: December 2017
$50,000 in dam mitigation grants and technical assistance

The third in a series of dam mitigation projects on Willow Creek within East Park, the dam was removed improve safety in the park and improve recreational opportunities.


Buffalo Before Photo
before removal

Buffalo Before Photo
before removal

Buffalo After Photo
after removal


Project: Manchester Whitewater Park

Manchester Whitewater Park

Begin Date: September 2014
Completion Date: Summer of 2015
IDNR Involvement: Provided a $200,000 Dam Mitigation Grant

Construction began in September of 2014 on the $1.8 million project. The new whitewater facility was funded in part by a $200,000 dam mitigation grant from the Iowa DNR. The whitewater park stimulates the local economy through increased use from paddlers, anglers and outdoor recreationalists including families who come down to picnic and watch at water’s edge. New local businesses rent out kayaks and inner tubes to tourists. Iowa's second whitewater park is another example of what can be done by removing or modifying low-head dams.


Manchester Whitewater Park Photo Gallery

Goldfield Dam to Rapids Conversion/Shell Rock River

Goldenfield Dam to Rapids Conversion/Shell Rock River

Begin Date: May 2014 
Completion Date: August 2014 
IDNR Involvement: $35,112 Mitigation Grant

A project to convert a former low-head dam into a small rock-arch rapids was completed in August, 2014. The project improved fish passage, navigation opportunities, angling access, and helped to stabilize eroding bluffs and create fish habitat upstream with three j-hook vanes. Iowa DNR supplied $35,112 in dam mitigation grants, and DNR mitigation staff assisted with project management, design, and construction supervision. Citizen donations and city funds covered the remainder of the $70,000 total project cost.


Quasqueton Dam Removal

Quasqueton Dam Removal

Completion Date: August 2014
IDNR Involvement: $68,000 Dam Removal Grant and Design

Contractors completed the project to convert the Quasqueton Dam into a rock arch rapids in late August. The project is on the Wapsipinicon River Water Trail in Buchanan County. DNR low-head dam mitigation grants of $68,000 and technical / design support helped make this project possible. 

Formerly, this dam led to situations like this rescue caught on video: Quasqueton Dam Rescue, 1993 [Youtube]


Elkader Whitewater Feature and Canoe Passage

Elkader Whitewater Feature

Begin Date: Fall of 2013
Completion Date: Spring of 2014
IDNR Involvement: $9,000 Dam Mitigation Grant

The Elkader Whitewater Feature and canoe passage was made possible by a strong local support system and with the help of a $9,000 dam mitigation grant from the Iowa DNR. “The Gobbler’, a standing wave feature, is proving to be a safe and challenging wave for play boaters. A canoe passage makes it easy for boaters to avoid the wave if they wish to just paddle past it.


Boone Waterworks Dam to Rapids

Boone during contruction

Completion Date: April 2014
IDNR Involvement: $184,000 Mitigation Grant, Design and Construction

It was a long winter of construction, but the Boone Waterworks Dam to Rapids Conversion project on the Des Moines River was completed in April of 2014.

Rockford Dam Removal

Completion Date: May 2014
IDNR Involvement: $30,000 Dam Mitigation Grant, Stream Restoration and Plantings

The Rockford Dam on the Shell Rock River was removed in 2014. Stream bank restoration immediately followed and has restored the river to a healthy habitat and improved navigation on a scenic part of the Shell Rock River for both paddlers and anglers.


Before Removal
before removal

After Removal
after removal