WC148 MayJune 2026 - Magazine - Page 31
The permit data also show that Ontario’s water story is not just
about one source. Surface water permits remain highly visible
across the province, particularly around lakes, rivers, and
northern and central water corridors. But groundwater and
combined-source permits from both surface and groundwater
are deeply embedded in the southern Ontario landscape. That
matters because it means the permit system is tracing multiple
forms of dependence at once: visible reliance on rivers and
lakes, and quieter but extensive reliance on aquifers, especially
in southern Ontario. Over time, increasing groundwater use is
also more visible in the permit data.
Who uses permitted water?
Sectoral patterns in the active permit data show why the
permit system matters, but also why simple counts need to be
interpreted carefully. Agriculture holds the highest number of
active permits in Ontario, followed by water supply. Commercial uses also remain significant, while dewatering construction
and industrial uses continue to reflect the close relationship
between water permitting, development, and infrastructure
activity. But Figure 3 adds another important insight: that
most sectors do not rely on a single source. Active permits span
groundwater, surface water, and combined-source takings,
showing that Ontario’s water users draw on different source
mixes depending on the type of activity and local conditions.
withdraw very large volumes. That distinction is one reason
Ontario’s open permit data is so valuable: it makes it possible
to look not only at how many permits exist, but what those
permits imply for regional and watershed demand, sectoral
pressure, future sustainability policy and planning.
Why groundwater deserves more attention
Groundwater is where the combined findings from the two
papers become especially important. One of the clearest results
is that groundwater is a very important part of Ontario’s water
use system. It supports agricultural, municipal, commercial,
and industrial demand across the province and is especially
important in southern Ontario. Of the 8,991 active permits
we analyzed in the dataset, 4,043 were for groundwater only
and another 2,624 allowed takings from both groundwater
and surface water. Taken together, that means more than 74
per cent of active permits engage groundwater in some way.
Geography reinforces the point. Groundwater permits are
concentrated most heavily in southern Ontario, where population
growth, agriculture, commercial activity, and development pressures overlap. In many of these areas, groundwater can provide a
dependable source, especially during periods when surface water
availability is more variable. The result is a water-taking landscape
in which aquifers play a foundational role in supporting municipal, agricultural, commercial, and construction-related demand.
The data also allow for analysis of areas where groundwater is
critical for multiple water uses yet may also be under stress.
FIGURE 3. ACTIVE WATER PERMITS (N=8,991) BY MAJOR USE CATEGORY AND
WATER SOURCE 2023
This is where the permit data becomes especially useful for
policy. Water permits are not just a regulatory inventory. They
are a practical map of how water supports farms, construction
activity, industry, commercial operations, and community
water supply. They also show the diversity of users that depend
on regulated access to water across the province.
At the same time, the number of permits in a category does
not tell us which sectors withdraw the greatest volumes. A sector can hold many permits but use relatively modest amounts
at each site, while another sector may hold fewer permits but
WAT E R C A N A D A . N E T
FIGURE 4. GEOSPATIAL DISTRIBUTION OF GROUNDWATER PERMITS IN ONTARIO,
1960-2022.
This is why the groundwater findings matter beyond statistics.
Ontario has strong policy attention around surface water quality,
watershed management, and source protection, yet groundwater
often remains less visible in public attention and related to water
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