Des Moines County supervisors review draft battery‑storage ordinance amid noise, setback and environmental concerns

Des Moines County supervisors spent a work session reviewing a newly drafted ordinance that would add a standalone section regulating commercial battery energy storage systems (CBEST), hearing extended public comment and debating noise limits, setback measurements, and environmental safeguards.

Rose Fisher, who identified herself as a retired auditor, told the board she had spent a weekend reviewing the draft and meeting videos and said, "it appears that regional planning has been selective about what changes were made or not made" — citing examples she said were discussed but not reflected in the draft. The board and staff agreed commenters should send consolidated lists of discrepancies to staff (Sarah or Zach) by Thursday so the packet can include proposed corrections before a formal review session in about two weeks.

Presenter staff described the new article as a county‑level standard that "shall apply to all commercial energy storage systems developed under the authority of this ordinance," and walked supervisors through technical provisions adapted from other counties and best‑practice guides. Key elements discussed included how setbacks are measured (to the closest point of battery equipment), a waiver process where individual property owners may grant written permission for shorter setbacks, and separate setback tables for installations using lithium‑based chemistries versus non‑lithium systems.

Noise was a central source of contention. The draft includes a new noise section that reduces the limit for sound from certain CBEST components to 50 weighted decibels measured from an occupied dwelling or civic building on a participating property; presenters said the earlier draft used 55 dB. Several speakers compared alternate approaches used by neighboring counties, noting Henry County uses a 60 dB baseline with tiered adjustments. Fisher and other commenters also cited industry materials — saying chiller units or cooling equipment are sometimes rated at 70 dBA — and asked how a full installation's combined sound would be measured and enforced.

On the question of who sets the number, supervisors emphasized elected members set policy even as staff and counsel provide technical and legal advice. One commenter noted the assistant county attorney had recommended 45 dB; supervisors said attorney input is advisory and that policy decisions rest with the board.

Board members also reviewed operational safety measures drawn from emergency‑responder guidance: locked, fenced entries meeting National Electric Code standards; required hazard signage including battery chemistry and 24‑hour operator contact information; and vegetation or physical screening considerations. Presenters said fencing near public right‑of‑way would be designed to limit snow drift impacts and could be waived with an operator's study.

Environmental protections added after consultation with Des Moines County Conservation include mandatory consultation with the Iowa DNR and the local conservation district for sites near sensitive features, requirements for secondary containment capable of capturing electrolyte leaks, and a quarterly sampling and reporting regime during the first year of operation (testing pH, specified metals and lithium). The draft requires an action plan and remediation if tests exceed applicable thresholds, with results provided to the conservation board.

Supervisors debated a proposed clause that battery technologies and materials must have been used in at least two projects of a specified scale within 250 miles and operational for five years; some members said that standard helps avoid experimental deployments, while others worried it may be legally or practically restrictive for battery technologies.

Speakers discussed mitigation options for noise — from vegetative screening to sound walls — weighed against fire‑safety and maintenance needs. Several members suggested staff research proven sound‑attenuation measures used at other installations before finalizing requirements.

During public comment a resident proposed placing the question of permitting such projects on a countywide ballot. Supervisors and counsel said the legal mechanics and constitutional limits of citizen referenda on land‑use and property rights are complex and uncommon at the county level; they agreed to explore whether statutory petition routes exist but did not commit to a referendum.

No formal vote was taken. The board asked residents and reviewers to send consolidated comments to staff for packet inclusion; a formal review session was scheduled roughly two weeks out to consider edits and outstanding questions.

The board adjourned with plans to continue the ordinance review at the next scheduled work session.