Grid Down Danger Map

Continental US & Canada · urban exodus zones · reactor fallout sectors · first 180 days Day 0 · Decision window

Timeline after the grid fails

0hours in

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Decision window

Cities

Reactors

Wind driving the fallout

Wind FROM 270° W → plume drifts east

Layers

Urban exodus zones (grow with time) Nuclear plants (54 US + 4 Canada + restarts) 10-mi plume & 50-mi ingestion zones Downwind fallout sectors Grid interconnection seams (approx.) Labels

Check a location

Click anywhere on the map to grade that spot for the current day and wind.

First 72 hours

Confirm it is grid-down, not a local outage: no cell, no radio stations, ATMs and pumps dead across towns.H+0–2 Fill every container with tap water before pressure drops (towers drain in 12–48 h).H+0–6 Cash out of the city before fuel is gone and roads jam. Full tank, pre-staged route, no interstates.H+6–24 Be 100+ miles from any metro over 1M and outside every red circle on this map.H+24–72 Destination is upwind of reactors, has its own water, and has people you already trust.H+72

How the sectors are drawn

Each plant gets a 10-mile plume-exposure zone and a 50-mile ingestion zone, the two emergency planning zones US regulators use. The wedge is a 50° sector pointed where the wind carries a release; its length grows from 60 to 220 miles as the timeline advances. Winter and Summer swap in seasonal surface-wind patterns by region. Real plumes bend with the weather of the day, and Fukushima's worst hotspots were 20–30 miles out in a narrow band, so treat wedges as direction and order of magnitude, not a boundary.

Why reactors are not the day-one problem

On loss of grid every US reactor scrams automatically. Emergency diesels start in seconds; sites hold roughly a week of fuel and have post-Fukushima portable pumps and generators meant to be refueled from off site.
Core damage follows within hours to a day once all cooling stops. Spent fuel pools heat much more slowly; with a recent refueling discharge they can boil down in days to a couple of weeks, otherwise weeks to months.
So the reactor hazard sits behind the urban hazard: the map keeps plants quiet for the first week, ramps risk from day 7 to day 45 as fuel deliveries fail, and treats sectors as fully hot after day 60. Nobody knows the real curve; it depends on whether operators can keep trucking diesel.
Metro circles start at a size scaled to population and grow about 80% by day 60 to reflect people walking out along highways looking for food.

Sources & assumptions

Plant list: EIA, 54 operating US plants / 94 reactors as of March 2026, plus Palisades (MI) and Crane/TMI-1 (PA) restarts and Duane Arnold (IA) planned restart; Canadian plants from CNSC.
Metros shown: every US metro area over 500,000 people and every Canadian metro over about 200,000 (Canada is sparser, so its mid-size cities carry more regional weight). Populations are 2024 estimates, rounded; labels appear for metros over 2M.
Wind bearings are regional climatology, not a forecast. Switch to Custom and set the wind yourself if you have a local reading.
Built from the Jonathan Hollerman / Resilient Show grid-down interview (Sept 2026). Planning aid only.

Drag to pan · scroll to zoom · click to grade a spot

Metro exodus zone

Nuclear plant

Fallout sector (downwind)

10 / 50 mi planning zones