The boom in artificial intelligence has put Ontario municipalities on the front lines of a major debate over how to regulate a new wave of large, energy-hungry data centres.Several municipalities have voted in recent months on temporary data centre moratoriums while they study possible guardrails, and at least one has amended its bylaws to specifically permit them on industrial lands. Here’s a brief look at what some Ontario municipalities have done, and plan to do: HAMILTON The city was the first in Canada to vote on a one-year data centre freeze, what’s called an interim control bylaw. The proposed moratorium easily cleared committee but was voted down by council in July after a closed-door session with the city’s legal team. City staff are still carrying out a data centre planning study to look at possible guardrails, from energy demand to noise pollution. OAKVILLEThe town became the first in Ontario to get a moratorium past the finish line last month, while staff carry out a planning study. While Oakville officials said it had no formal data centre applications, developer Hive Digital Technologies in May announced plans for a 320-megawatt AI facility in the Greater Toronto Area targeted for the second half of 2027.SAULT STE. MARIECouncil directed staff last month to draft a moratorium on data centres with energy demands over 50 megawatts. A vote on that moratorium is expected on Sept. 21. GREATER NAPANEEThe municipality in eastern Ontario passed a bylaw in February to include data centres as a permitted use in the town’s industrial lands.TORONTOCouncil directed staff in July to review the city’s planning policies around data centres and pressed the province to come up with an Ontario-wide framework. Staff were also told to alert city councillors about any large data centre applications.OTTAWACity council directed staff last month to study and develop an assessment framework for data centres, including possible amendments to city policy. Until that framework is brought to council, staff were told to make council aware of any large-scale data centres to allow for the city to potentially consider case-by-case moratoriums to manage community impacts. MILTONThe town on Monday directed staff to study data centres, but voted down an interim control bylaw. BURLINGTONCouncil in July voted down a bid to pursue a temporary moratorium but directed staff to study the city’s rules around data centres. WATERLOO REGIONThe regional municipality in August directed staff to report back to council early next year on possible data centre development implications.