Quaker Mill Dam Mitigation

Manchester, IA

Services:

• Hydrologic & Hydraulic Modeling
• Dam Mitigation
• River Restoration
• Planning and Design

Service Area:

• Water Resources
  • Dam Mitigation
  • River Restoration

Market Sector:

• State

The existing Quaker Mill Dam is a low head concrete dam built in the1920s located on the Maquoketa River in Manchester, Delaware County, Iowa.  The dam was originally built to generate electricity but it stopped working prior to being purchased by a private owner.  Levee breaches during floods in 2008 and 2010, caused formation of a new river channel that joined Honey Creek and created erosion concerns at the downstream Honey Creek Bridge.

Delaware County and Iowa DNR propose to repair the breached levee area, create a new re-meandered river channel, and mitigate the low head dam.  Repairing the levee breach will return the Maquoketa River back to its original flow path and alleviate flooding and erosion concerns along the breached channel, Honey Creek, and the Honey Creek Bridge.  The new re-meandered river channel, based on natural channel design methodology, will provide increased river length and access to floodplain area.  Mitigation of the dam will eliminate safety and maintenance concerns associated with the dam and will allow for aquatic organism passage.  The existing dam will be removed and replaced with a constructed rock rapids structure. 

LT Leon provided technical assistance to the Iowa DNR including, field reconnaissance, hydraulic and hydrologic modeling, and a hydraulic analysis summary report.