County engineers, Ameren to meet on floodplain ordinance issues and FEMA mapping

Iroquois County staff told the Tax Planning and Zoning Committee on May 6 that Ameren has responded to the county’s letter outlining 10 technical concerns about a proposed floodplain-related project and that engineers from both sides are scheduled to meet to resolve remaining issues.

The county has identified three outstanding technical items: a needed floodplain map revision that staff said should be handled through the Federal Emergency Management Agency process; compensatory-storage questions that arise where the county ordinance generally prohibits bringing in fill from off-site; and soil and groundwater conditions limiting the amount of effective storage available for a proposed mitigation design.

"We got a response back from Ameren late last week saying that they would love their engineer to talk to our engineer, and there's a plan of meeting sometime this week for the engineers to talk," the committee chair said during the update.

County staff and the county engineer previously sent Ameren a list of technical concerns. County engineers reviewed Ameren’s responses and flagged three more detailed issues needing technical discussion: whether FEMA’s map-revision process will establish elevations acceptable to the county, how compensatory storage can or cannot be credited if fill would come from outside the development parcel, and the practical limits created by high groundwater and low-permeability soils.

Staff said the parties are attempting to resolve the issues before the county’s building season. The county’s attorney and engineers will continue direct discussions with Ameren’s engineers. The committee was told that Ameren has indicated willingness to engage in technical talks and that several of the county’s earlier concerns appear to be narrowing.

The committee requested staff continue updates as the engineer-to-engineer discussions proceed.