Overview
- Mississauga city council voted unanimously to impose a one-year moratorium on new data centres above 10 megawatts on Wednesday, Sept. 16, 2026, putting a proposed 40-megawatt Prologis project in Meadowvale Business Park on hold.
- The measure follows Oakville’s earlier one-year freeze and leaves Ontario with a patchwork of responses as some cities pursue moratoriums while others direct staff to study rules or reject pauses.
- Ontario released a draft data-centre playbook in August that asks projects to pay for their electricity impacts and show community benefits but offers limited enforcement, prompting cities to act locally.
- Residents and councillors have cited concrete concerns about high electricity and water use, noise and backup generators, and floodplain siting, which together drove Mississauga’s decision to study guardrails.
- Next steps include municipal planning reviews, possible appeals to the Ontario Land Tribunal by developers, and scrutiny over who will pay for grid or transmission upgrades and their cost to ratepayers.