PLANADA LAB · № 03

Two Crises,
One Map

Calgary's blanket rezoning fight and its water infrastructure crisis are the same fight. Neither side has measured it.

Pipe network · install year

pre-1950

1,883

1950 – 1969

8,683

1970 – 1989

17,110

1990 – 2009

22,097

2010 +

10,967

Overlay

R-CG infill permits

1,499

R-G permits

476

H-GO permits

128

Historical breaks

5,152

Bearspaw feedermain

PCCP

View mode

All

Full network + every R-CG permit since blanket rezoning

Conflict zones

Only R-CG permits within 200m of a pre-1970 main

Old network only

Pipes installed before 1970 — Calgary's risk cohort

v0.3 · risk ● live data

Loading 60,740 water mains

The finding

2.2×

R-CG infill is concentrated on pre-1970 mains at 2.2 times the citywide rate. 37% sits on pipes older than Bearspaw was when it broke.

RISK DRILL-DOWN

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NEAREST R-CG PERMITS

CALGARY · 51.04°N 114.07°W

Hover details

Hover any pipe segment or red permit dot for details. Click anywhere on the map for a 1km area audit.

What we found

The pipes that are failing right now are exactly the cohort we're flagging

51% of every Calgary water main break in the last 4 years happened on pipes installed 1950–69 — a cohort that's only 14% of the network. 95% of recent breaks are on pre-1990 pipes. Modern plastic = 56% of the network, 5.8% of breaks. Median age of a broken pipe: 62 years vs Calgary's median of 34. This isn't a forecast — it's a description.

R-CG permits are 6× concentrated in high-break communities

Top-10 break communities = 3% of Calgary's communities. They hold 19% of all R-CG permits since blanket rezoning (6× chance rate). Top-25 break communities hold 39% of permits. 34% of all R-CG permits are in just 10 communities. Bowness alone: 120 permits + 36 recent breaks. Permit volume doubles right before council votes on repeal — developers racing the window.

Calgary has more pipe per resident than any major Canadian city

4.2 m/user vs Edmonton 4.0, Ottawa 3.2, Montreal 2.7, Toronto 1.7, Vancouver 0.6. The Bearspaw review found this sprawl-driven over-extension is what made the 2024 failure catastrophic.

Cast iron from the 1950s-60s breaks 30× more than modern plastic

Empirical cohort rate: 0.182 breaks/km/year vs 0.006. Computed from 37,487 documented breaks across 5,419 km of mains, joined by true point-to-line distance (100% match rate). Confirmed by walking forward: iron pipes are 56% of recent breaks despite being only 15% of the network.

Inspections deferred three times before the first failure

Bearspaw was flagged for inspection in 2017, 2020, and 2022. All three deferred. Ruptured June 2024, again Dec 30 2025, then proactively shut down March 2026 for emergency reinforcement. Mayor calls more breaks the "new reality" until replacement completes Dec 2026.

Sources: City of Calgary Open Data
· w6h9-w33i (Public Water Main, 60,740 segments)
· dpcu-jr23 (Water Main Breaks, 37,487 records)
· 6933-unw5 (Development Permits)

Bearspaw South Feedermain Independent
Review Panel, Final Report (Jan 2026).