Session 1 · TRACE: Causes & Consequences
Rain, land and rivers
- 10 minCyclone Gabrielle, February 2023: a warm, wet storm dropped huge rain on hills in Hawke's Bay and Tairāwhiti. Predict: what on the land could make a flood worse?
- 20 minRunoff trays: pour the same amount of 'rain' onto a tray of sponge or turf and a tray of plastic sheet. Measure how much water runs off and how fast. Link to forests, farms and concrete.
- 15 minTopographic map: find a river, a stopbank and houses on flat land on a Topo50 map. Use four-figure grid references to name three places at risk.
- 5 minDirect or indirect? Sort consequences: a house flooded, a road closed for months, a job lost at an orchard, a family moving town.
Session 2 · TRACE: Causes & Consequences
Should people move? Managed retreat
- 10 minBig idea: managed retreat means planning to move homes and roads away from places that will keep being hit. After Gabrielle, some Hawke's Bay land was judged too risky to rebuild on.
- 25 minRole-play a community hui for a made-up valley: a farmer, a kuia whose whānau have lived there for generations, a council engineer, an insurer, a young family. Each role card gives their interests. Aim for a decision everyone can live with.
- 10 minStep out of role. Whose voice was hardest to hear? What would be lost and what would be gained by moving?
- 5 minStart your whānau plan: meeting place, out-of-town contact and grab-bag list.
Getting started
Use a cause-and-consequence chain template: rain → land → river → people → months later.
Stretch
Find out how Christchurch's residential red zone along the Ōtākaro Avon River is being turned into a park. Is that managed retreat?
Checkpoint
Each student can explain two causes that made Gabrielle's flooding worse and one direct and one indirect consequence.
Activities for this week
- Runoff trays: land cover and floods: Does what covers the land change how much water rushes into a river?
- Managed retreat hui (role-play): When a place keeps flooding, who decides whether people should move?
- Grab bag and whānau plan: What would your household need for three days without power, water or shops?
Useful this week
- In the wake of Gabrielle ↗ Why Cyclone Gabrielle's rain and floods were so severe, and how forecasts were used.
- Floods ↗ Why New Zealand rivers flood and how people have tried to control them.
- Managed retreat ↗ What managed retreat means and how the government is approaching it.