Forty city leaders from around the world have united behind a framework designed to ensure that the explosive growth of data centers does not come at the expense of their residents' access to affordable energy, clean water, and livable communities.
The pact, announced Tuesday during London Climate Action Week by C40 Cities—an alliance of nearly 100 cities committed to climate action—represents an unprecedented effort by municipal governments to assert democratic control over how artificial intelligence infrastructure reshapes urban landscapes. The initiative emerged directly from concerns raised by the mayors of Phoenix and Melbourne, Australia, about data centers' massive consumption of electricity and water, and their competition with housing developers for scarce urban land.
"We found out that the challenges in every region around the world were very similar," said Cassie Sutherland, a managing director at C40. "Our approach was to say OK, how do we now use a global mayoral voice to come together with the conditions under which they will accept data centers."
The Scale of the Challenge
The urgency is clear. About 1,700 data centers already operate within C40 cities' networks, and development is expected to grow by over 40% in 50 of those cities. The infrastructure boom is driven by major technology companies seeking to locate data centers close to their operations and to markets demanding instantaneous artificial intelligence responses.
Phoenix exemplifies the pressure cities face. The metropolitan area ranks in the top 10 data center markets in North America, with pending permit requests that would double electricity demand if all proposed facilities were built. Developers are attracted to the region for its reliable power supply and predictable weather—factors that benefit corporate bottom lines but raise questions about who bears the costs.
Melbourne presents an even starker picture. If the city follows through on all its data center plans, these facilities will annually consume up to 20 billion liters (5.3 billion gallons) of water—approximately 4% of the city's entire drinking water supply. This occurs as the water supply is already strained by population growth, longer dry periods, and more extreme heat driven by climate change.
Democratic Accountability vs. Corporate Expansion
Political and local opposition has been growing as communities confront the real costs: fears of blackouts, rising electricity bills, and the centers' enormous water consumption. Some states are already suspending tax breaks or considering moratoriums on data center construction—a sign that public pressure is forcing recalculation of whether subsidizing these facilities serves the public interest.
The pact establishes standards intended to shift the terms of negotiation. Urban data centers should be built on abandoned or underutilized land, powered entirely by renewable energy with battery storage, and designed to reduce water use and emissions. The framework also requires that facilities create jobs, purchase local goods and services, pay for their own infrastructure upgrades, and genuinely listen to community feedback.
Phoenix Mayor Kate Gallego articulated the core concern: "We understand the importance of this innovation, it's creating great jobs in our community. We just want to make sure that we get it right for our local residents and for the health of our planet." She emphasized that current data center investments are worsening climate change while failing to meet community needs.
Melbourne's Lord Mayor Nicholas Reece framed the stakes in terms of equity between cities: "We don't want to see a race to the bottom between cities where governments, desperate for investment, are chasing data centers on any terms possible. We want to see a better framework in place so that the investment rush in data centers can be a win-win — a win for investors and also a win for local communities."
Global Reach, Significant Gaps
About half of the 40 participating mayors are from the United States, including leaders from Seattle, Palo Alto, Riverside, Phoenix, Albuquerque, Beverly, Lincoln, Chicago, Cleveland, and Miami. European signatories represent cities in Greece, Spain, Italy, Germany, the United Kingdom, and Norway, alongside Montreal. African cities from Ivory Coast, Sierra Leone, South Africa, and Kenya have also joined, as have cities in India and Australia, and Lebanon.
However, a critical gap remains: as of Tuesday, no Southeast Asian cities had endorsed the pact. This absence is significant given that the region accounts for a quarter of global energy demand growth, with more than 2,000 data centers operating across Indonesia, Malaysia, Singapore, Thailand, Vietnam, and the Philippines. The International Energy Agency projects that annual energy demand from these data centers will more than double within five years.
C40 indicated that several Southeast Asian cities cited national policies or other complications preventing endorsement, though conversations continue.
Implementation and Limits
Sutherland acknowledged that translating the pact's vision into action requires more than mayoral goodwill. Each city must develop its own regulations or guidelines based on the framework, and mayors face structural limitations in what they can accomplish unilaterally. Success depends on buy-in from other government officials, utilities, and the private sector—a recognition that market-driven development requires democratic oversight and coordination to serve public interests.
Why This Matters:
This pact represents a critical moment in how cities assert collective power over infrastructure development that affects their residents' fundamental access to affordable energy and clean water. As artificial intelligence drives unprecedented demand for data centers, the question of whether this infrastructure serves public benefit or merely corporate expansion has become urgent. The framework signals that mayors are unwilling to accept a "race to the bottom" where communities desperate for investment sacrifice environmental and resource protections. With energy demand from data centers projected to surge and water scarcity intensifying due to climate change, establishing standards that require renewable energy, water efficiency, and community accountability is essential. The notable absence of Southeast Asian cities—a region facing the most severe projected growth in data center energy demand—underscores how national policies and power imbalances can limit cities' ability to protect their residents. This pact's success will depend on whether mayors can translate their unified voice into binding regulations that prevent corporations from simply relocating to jurisdictions with weaker protections.