South Bend, Indiana Mayor James Mueller issued an executive order on 17 September prohibiting city staff from entering into non-disclosure agreements (NDAs) tied to data-center projects, a move that crystallised a weeks-long fight over how much the public gets to know about industrial wastewater flowing into the city's treatment plant (WSBT).
Key takeaways
- Mayor Mueller signed an executive order on 17 September barring future NDAs about data centers after an Amazon-related secrecy agreement surfaced (WSBT).
- Amazon used about 30 million gallons of the South Bend Wastewater Treatment Plant's capacity between 1 August 2024 and the end of July 2025, making it the 11th-largest user (WSBT).
- The plant's top three users are Cleveland-Cliffs (about 455 million gallons), Notre Dame (about 287 million gallons) and the South Bend Ethanol plant (about 164 million gallons) (WSBT).
- Council members Oliver Davis Jr. and Sherry Bolden-Simpson filed a separate ordinance that would impose a $2,500 penalty and review past secrecy agreements; the mayor has said he would veto it (WSBT).
- Mayor Mueller characterised the order as largely symbolic, telling Louisville Public Media: "People get ideas when they hear the term but in actuality nothing was prevented from being released by this agreement" (Louisville Public Media).
What happened
The South Bend Wastewater Treatment Plant sits on the city's northwest side, about 15 miles from Amazon's data center, and treats sewage piped in from industrial users across the region (WSBT). According to city records, the plant served Amazon's facility from at least 1 August 2024 through the end of July 2025, processing roughly 30 million gallons over that period — enough to make the data center the plant's 11th-largest user (WSBT).
Behind that routine discharge figure is the political flashpoint. The city's Department of Public Works confirmed it has "entered into agreements that allow wastewater from the development to be treated at the city's wastewater treatment plant," and the original NDA between the public works team and Amazon was signed in December 2023 (WSBT). Councilman Oliver Davis said he and other council members were never told Amazon was sending wastewater to the plant, a gap that came to light when Public Works Director Eric Horvath declined Councilwoman Sherry Bolden-Simpson's invitation to discuss the contents of that wastewater with a council committee (WSBT) (Louisville Public Media).
Davis and Bolden-Simpson responded with an ordinance that would block future NDAs, require more disclosure about data centers and waterworks, review past secrecy agreements, and carry a $2,500 penalty (WSBT). Mayor Mueller countered that the council, as the legislative branch, cannot dictate how the executive branch executes contracts, and he said the underlying deal with Amazon has already cleared the Board of Public Works (Louisville Public Media). The council's ordinance was scheduled for first reading on 28 September, and it remained unclear whether the mayor's executive order would supersede it (WSBT).
Specification read
The reported 30 million gallons used by the Amazon data center over a 12-month window is a steady, low-flow industrial input — roughly 82,000 gallons per day, or about 310 m³/day on a straight-line basis, well below the million-gallon-per-day tier that Cleveland-Cliffs, Notre Dame and the South Bend Ethanol plant each occupy at the same facility. Scaled to population equivalent using a typical domestic loading of about 200 L per capita per day, 310 m³/day corresponds to a design load of roughly 1,500 PE (general industry range, not from the sources). For a plant receiving hyperscale-data-center cooling and process wastewater alongside heavy-industry streams from a steelmaker, a university and an ethanol plant, the relevant treatment train runs screening → grit removal → primary clarification → biological treatment (typically a high-mixing activated-sludge or MBBR stage, with MBR selected where discharge limits or water-reuse targets are tight) → tertiary filtration → disinfection, with metals precipitation and DAF thickening called in where the industrial fraction drives the load. This event bears on the front end of that train — the trade-waste acceptance and pretreatment framework that decides which influent a municipal plant is willing to sign an NDA about in the first place. If your plant is a municipal facility accepting large data-center or hyperscale tenants in the low thousands of m³/day with elevated temperature, low BOD/COD, and tightening consent limits, the South Bend case is a signal to expect procurement-side pressure for transparent trade-waste contracts and pretreatment audits before discharge permits are renewed, which is precisely the scope covered by integrated sewage treatment packages and by the buyer-facing walkthroughs in Effluent Treatment Plant in Liverpool: 2026 Buyer's Engineering Guide and MBR vs Conventional Activated Sludge for Petroleum Wastewater in Smackover, US (2026 Engineering Guide).
FAQ
What did the South Bend mayor actually change with the 17 September executive order?
The order bars city staff from entering into NDAs tied to data-center projects going forward. The mayor told Louisville Public Media the change is largely symbolic, arguing the existing Amazon agreement did not actually block any disclosure (Louisville Public Media).
How much wastewater is the Amazon data center sending to South Bend?
City records show Amazon used about 30 million gallons of plant capacity between 1 August 2024 and the end of July 2025, making it the 11th-largest user of the South Bend Wastewater Treatment Plant (WSBT).
What would the council's proposed ordinance do that the executive order does not?
The Davis–Bolden-Simpson ordinance would also review past secrecy agreements and impose a $2,500 penalty for non-compliance, which the mayor's order does not address. The mayor has said he would veto the ordinance, and its first reading is scheduled for 28 September (WSBT) (Louisville Public Media).
What does this mean for plant managers weighing a trade-waste contract with a hyperscale data center?
Expect buyers to ask for transparent trade-waste terms, pretreatment audits and disclosed discharge limits before signing, and to budget for a packaged municipal wastewater train sized to the tenant's expected flow. Hard capex was not reported for the South Bend case, so any cost figure should be treated as a general industry range, not a sourced number (general industry range, not from the sources).
