The Corps was directed by Congress through the Water Resources Development Act of 2007 to study a range of factors that could potentially reduce the effectiveness of the electric dispersal barriers. The Corps has assessed various technical, environmental and biological factors.
- Interim Report I: Identifies areas of potential bypass and led to the construction of fence and concrete barriers along the Des Plaines River and a stone blockage in the Illinois and Michigan Canal. These measures reduce the risk of any Asian carp potentially bypassing the barriers during flooding. You can watch a short video overview.
- Interim Report IIA: Provides an evaluation of tests conducted through 2011 to determine the optimal operating parameters for the barriers. Subsequent research on optimal operating parameters is ongoing and results are presented in other interim reports.
- Interim Report III: Presents an evaluation of the potential for risk reduction that might be achieved through changes in the operation of structures in the Chicago Area Waterway System (CAWS), such as locks, sluice gates, and pumping stations. The report led to the construction and installation of bar screens for two sluice gates at both the O’Brien and Chicago locks.
- Interim Report IIIA: Considers how technologies such as bubbles, lights and sounds can inhibit Asian carp movement and recommends construction of an acoustic bubble curtain with strobe lights as a demonstration project.
- Interim Report IV: Documents the results of ongoing testing and analysis related to the barriers, includes a systematic risk assessment of identified barrier failure modes, and identifies ongoing risk reduction efforts. Links to files: Dispersal Barrier Interim IV June 28, 2019; Interim IV Appendix A; Interim IV Appendix B
- Interim Report V: The Interim V Report will be completed in 2022. The objective of Interim V is to further optimize the operation of the barriers system. A plan will be developed to set operational protocols based on biological and environmental monitoring. Residual risks of barrier bypass mechanisms from Efficacy IV will be reviewed and mitigation strategies for remaining risks will be considered. Cost estimates and benefits (reduction in risk) will be assigned to specific mitigation measures and an analysis will be completed to identify potential combinations of measures that are cost effective. The analysis will be used to develop a recommended plan for implementation of measures to further improve barrier effectiveness.