WATERLOO REGION — July 17, 2026 — Waterloo Region has restored enough water capacity to restart some stalled development, but the breakthrough does not fully resolve the infrastructure constraint that has complicated housing and economic growth since late 2025.
The Region announced July 7 that 30 litres per second of capacity was ready to be assigned to municipalities within the Mannheim Service Area. Ten litres per second is available immediately, while another 20 litres per second is expected this fall when a temporary filtration project at the Mannheim Water Treatment Plant enters service.
Regional officials estimate the combined capacity could support housing for as many as 10,500 residents and accommodate up to 5,000 jobs. The actual mix will depend on which projects receive allocations and how much water each one requires.
The development has been presented as a turning point, but not an end to the problem. The Region remains reliant on temporary equipment, accelerated repairs, transfers between parts of its water system and a series of longer-term infrastructure projects.
A capacity constraint, not unsafe drinking water
Although the situation is frequently described as a water shortage, officials say it is more accurately a constraint on the system’s ability to serve future growth.
The Mannheim Service Area supplies Kitchener, Waterloo and parts of Cambridge, Wilmot and Woolwich. The issue concerns how much water the Region can safely pump, treat, store and distribute while completing maintenance and preserving operational reliability.
It does not mean existing residents are about to lose water service or that the water coming from household taps is unsafe.
The constraint was identified in late 2025 after the Region revised the method it uses to calculate available supply. Officials cited rapid growth, aging treatment equipment, infrastructure requiring maintenance and lower available capacity in parts of the system.
Construction on developments with existing approvals and servicing commitments has continued. The Region says those projects include homes intended for approximately 14,000 residents. The most serious disruption has affected projects seeking new servicing commitments.
Development and construction organizations have said the uncertainty delayed projects, financing and investment. A coalition representing builders, contractors and real-estate interests told regional council in June that thousands of jobs and hundreds of millions of dollars in investment had been affected. Those figures were industry estimates rather than an independent regional calculation.
How the Region found more capacity
The 30 litres per second being released this summer and fall comes from more than one source.
Ten litres per second was identified by adjusting how existing wells are operated. The Region describes the process as optimizing the broader system—drawing more efficiently from some wells while attempting to protect the long-term sustainability of others.
The remaining 20 litres per second is expected from the Mannheim side-stream project. The temporary system will use modular ultrafiltration equipment to treat part of the water at the Mannheim plant while larger upgrades continue.
Regional officials initially expected the 20 litres per second to be available by the end of September. Its final availability remains dependent on installation, commissioning and successful operation of the equipment.
The Region’s longer-range plan calls for adding as much as 600 litres per second by 2032, with nearly half expected to become available during 2027. Those projections depend on numerous well, treatment and distribution projects being completed as planned.
The financial impact is still developing. A July report to regional council examined the capital and operating commitments associated with the response, along with possible effects on the Region’s water reserve and future rates. The Region says outside funding—particularly provincial assistance—will be the largest factor in limiting pressure on water bills.
Municipalities must choose who receives water
The Region is not assigning capacity directly to individual subdivisions, apartment buildings or businesses. Instead, it is distributing portions to the affected municipalities, which must decide which projects receive permission to use their limited supply.
That has created a new policy question: when there is not enough capacity for every project, what should be built first?
Kitchener’s allocation framework gives weight to affordable housing, essential services, economic development, infrastructure availability, environmental effects and whether a project is ready to begin construction.
Waterloo council approved its own policy July 13. It also places an emphasis on affordable housing and project readiness.
The policies could allow municipalities to direct capacity toward developments offering a greater public benefit. They could also create difficult comparisons between rental housing, ownership housing, factories, offices, public institutions and other proposed uses.
A project may have planning approval and still wait for water capacity. Conversely, a project offering affordable units or another community benefit could move ahead of an older application, depending on how the local scoring system is applied.
Transparency will therefore become an important part of the next phase. The public will need to know which projects receive allocations, how much capacity they consume and what benefits developers promised in exchange for priority.
Wilmot groundwater dispute remains unresolved
Some of the effort to stabilize the Mannheim system has involved transferring water from Wilmot Centre.
In April, regional council rescinded a policy dating to 1980 that limited the transfer of water from Wilmot Township to urban areas elsewhere in the region. Staff said the Wilmot Centre wells could support forecast growth in Baden and New Hamburg through 2051 while contributing approximately 30 litres per second to the Mannheim system.
The decision faced opposition from residents concerned about private wells, wetlands and the cumulative effects of increased groundwater pumping. Critics argued that the Region should proceed more cautiously and improve its response when private wells are affected.
Regional staff said monitoring and long-term data supported the transfer. The Region is also updating its well-interference policy, which determines how complaints from private well owners are investigated and addressed.
The disagreement illustrates a broader tension in the water strategy: communities containing groundwater sources may bear environmental risk while much of the new development occurs elsewhere.
What is known about the proposed AI data centre
Concerns about water allocation have increasingly become connected to reports of a large AI data centre in Wilmot Township.
The most important fact is that no Wilmot data centre has been publicly confirmed for construction.
In August 2025, Quebec-based QScale confirmed that Waterloo Region and Wilmot Township had been shortlisted as possible locations for an Ontario expansion. The company said it was evaluating several sites and would release more information after completing that assessment.
Publicly available information reviewed for this article does not establish that QScale has selected a Wilmot property, submitted a local planning application, received water capacity or obtained construction approval.
QScale’s chief executive also said the company was not interested in using the 770-acre Wilmot industrial land assembly. Waterloo Region Economic Development Corporation CEO Tony LaMantia likewise said the potential data-centre project and the controversial farmland assembly were not connected.
That distinction has sometimes been lost in online discussion, where a possible Wilmot project has been described as though it were approved and ready to build.
The proposal nevertheless raises reasonable questions, particularly while water for housing and other development is being rationed.
Data centres can use water directly for cooling and indirectly through the electricity required to operate them. Their demand varies substantially depending on facility size, computing equipment, cooling design, climate and whether heat is rejected through evaporative towers, dry coolers or other systems.
QScale promotes advanced cooling, renewable power and waste-heat recovery at its facilities. A technical assessment of its existing Q01 campus in Lévis, Que., states that the site uses dry coolers and does not consume water for cooling.
That does not establish what technology would be used at a possible Ontario facility. No site-specific design or independently verified estimate of water consumption for a Wilmot project has been made public.
Closed-loop liquid cooling can sharply reduce continuing water consumption because coolant is recirculated rather than routinely discarded. But the phrase “closed loop” alone does not answer every question. A facility can circulate liquid internally while using a separate evaporative system to reject heat outside the building. A complete assessment would need to identify both systems, expected annual water use, peak summer demand and the source of any water.
Electricity may be the larger infrastructure issue. AI computing facilities can require very large and continuous power supplies, potentially requiring new transmission infrastructure. QScale’s recent expansion at its Quebec campus is adding 60 megawatts of computing capacity, although there is no evidence that a possible Wilmot facility would be the same size.
Questions that must be answered before approval
If a data-centre application moves forward locally, residents and councillors will need site-specific information rather than assumptions based on other facilities.
That should include:
- The project’s average and peak potable-water demand.
- Whether cooling is dry, evaporative or a combination of both.
- How much water would be required to initially fill and periodically maintain the system.
- Its electricity requirement and any necessary grid upgrades.
- Whether backup generators would affect local air quality.
- The number of construction and permanent jobs.
- Whether public incentives or infrastructure subsidies are being requested.
- Whether waste heat would actually be captured and used.
- How the project would be ranked against housing and essential services under a municipal water-allocation policy.
Until those details exist, it would be inaccurate to say a Wilmot AI data centre is consuming—or has been promised—part of the newly released water capacity. It would be equally premature to dismiss concerns about the potential demand of a multibillion-dollar industrial project.
Improvement, but not a return to normal
The release of 30 litres per second means some projects can move forward after months of uncertainty. It also gives the Region time while larger additions are designed and constructed.
But it introduces a period in which local governments will explicitly choose among competing forms of growth. Those choices will determine whether the first available water supports affordable homes, market-rate development, public services, conventional industry or emerging uses such as AI infrastructure.
For residents, the immediate drinking-water supply remains safe. For builders and institutions waiting to grow, capacity remains limited. And for the possible data centre in Wilmot, the central questions—where it would be built, how it would be cooled and how much water and electricity it would require—remain unanswered.