Experts tell Champaign County task force: require peak‑day reporting and disclose cooling design

Researchers and water experts on June 8 urged Champaign County officials to require standardized disclosures from data‑center applicants, including projected peak‑day water withdrawals, whether cooling is consumptive, and the facility’s power‑source mix.

Joanna Dakota Smith of the Alliance for Water Efficiency told the task force that communities must distinguish direct site water use from indirect water demand created by electricity generation. “Not all water use associated with a data center is occurring at the data center itself,” Smith said, explaining that the power plant supplying electricity can add a large off‑site water footprint depending on the fuel mix.

Lincoln Institute and University of Illinois researchers presented state case studies showing where concentrated local demand creates vulnerabilities. Haridi (research team) said national averages can obscure hotspots: a single large facility can use a disproportionately large share of a region’s water during peak demand days and recommended planning boundaries, peak‑day metrics and requiring developers to disclose consumptive versus non‑consumptive volumes.

Both presenters emphasized trade‑offs. High capacity facilities often rely on liquid or component‑level cooling that can be more water‑efficient per unit of heat removed but may still increase total local consumption if overall capacity is higher. Experts also warned that “closed loop” claims require scrutiny: a closed loop at chip level can be coupled to an open, evaporative loop elsewhere in the facility.

Recommendations the presenters urged the task force to adopt or include in standard application materials: pre‑development projections of water and electricity use (including peak day), specification of all cooling loops and endpoints, disclosure of any proprietary cooling fluids and their disposal path, and consideration of wastewater reuse and offsite thermal discharges.

Members pressed for specifics on reporting and enforcement. Presenters pointed to recent Virginia steps to require disclosures and to IEPA permitting as the mechanism for any discharge to surface waters; they said Illinois lacks a statewide wastewater‑reuse mandate. Task force staff said they will draft standard conditions and circulate them for comment.