Senate Bill 1046, introduced June 18 by Sen. Rosemary Bayer and cosponsored by Sens. Mallory McMorrow, Kevin Hertel, Darrin Camilleri and several other Senate Democrats, would require Michigan’s Department of Environment, Great Lakes, and Energy to publish the total water used by each data center within each public water supply’s service area during the previous calendar year. The first report would be due July 1, 2027, with public water systems submitting underlying data to EGLE by June 1 each year. The bill is part of a broader eight-bill package Senate Democrats introduced in June addressing data center water use, electricity rates, labor requirements and community benefits.
The Disclosure Provision Goes Beyond the Largest Water Users
SB 1046 separately would create a new permitting system, beginning July 1, 2027, for facilities using or expected to use at least 550,000 gallons per day for consumptive purposes on an annual average, with consumptive use capped at 2 million gallons per day for permit holders and applicants required to hold at least three public hearings. Those facilities would be barred from withdrawing water directly and would instead have to partner with a permitted community water supply. But the disclosure provision is written more broadly: it directs public water supplies to report the total usage of each data center in their service area regardless of size, which could give communities a facility-level record they typically do not have today.
Researchers Identified the Underlying Data Gap
That transparency issue was flagged this year by University of Michigan researchers, who found in an April 2026 groundwater strategy report that the state had 74 operating data centers and another 16 proposed projects as of that month. The report also found that while Michigan’s tax incentive structure requires enterprise data centers to connect to a public water supply, facilities that do so are not required to publicly disclose individual usage, an arrangement the researchers described as creating a “significant transparency and information gap.” SB 1046 would directly narrow that gap by reporting the amount attributed to each facility rather than aggregate public-system demand, an approach that mirrors disclosure requirements moving through Vermont’s legislature and Washington’s newly enacted reporting framework.
Facility-Level Data Could Separate Very Different Water Profiles
Water demand depends heavily on facility size, cooling architecture, local climate and operating practices, and the University of Michigan report notes hyperscale and large colocation facilities account for 84% of direct data-center water use nationally. Not every large facility follows that pattern, though: a June Citizens Research Council of Michigan analysis found the planned 1.4-gigawatt Oracle/OpenAI Stargate facility in Saline Township is expected to use closed-loop cooling, meaning its direct water demand would primarily involve maintenance and fire suppression rather than continuous evaporative cooling, exactly the kind of distinction facility-specific water data increasingly needs to make visible rather than treating every large campus as an equivalent water risk. Gov. Gretchen Whitmer has separately called on operators to minimize consumption and pay their share of infrastructure costs; SB 1046 would move part of that conversation from voluntary commitments to public, facility-level data.