Hazards
Senior 1 · Geography
Hazards
Lesson 4 of 4
25 min
On 26 December 2004 a ten-year-old British girl, Tilly Smith, was walking on Mai Khao Beach in Phuket, Thailand, when the sea began to froth and kept coming in. Two weeks earlier, in a geography lesson, she had learned that this is a warning sign of a tsunami. She warned her parents, her father alerted a security guard, and the beach was cleared minutes before the wave arrived. About 100 people were saved. Knowledge is part of a community's capacity (lesson 1). This lesson looks at hazards that people cause themselves, and then at how Rwanda prepares for all hazards.
Definition
Human-made hazard: a hazard caused mainly by people's actions, mistakes or conflicts rather than by natural forces. Example: a war, a road accident, a fire in a market, or pollution of a river.
Definition
Famine: a severe, widespread shortage of food that causes hunger, disease and deaths across a whole region. Drought is often the trigger, but famine is usually made worse by war, poverty or poor decisions. Example: the Ruzagayura famine of 1943–44.
Definition
Refugee: a person who has fled their own country because of war, violence or persecution and cannot safely return. Example: families from the DR Congo and Burundi living in camps such as Mahama in Kirehe District.
Wars kill and injure people, destroy homes, roads, schools and hospitals, cut off food and water, spread disease, leave land mines, and force people to flee. Conflicts in the Great Lakes region over the last three decades have driven many people from their homes. Rwanda's 2022 census counted 107,300 refugees living in the country, mainly from the DR Congo and Burundi; about half of them lived in Kirehe District, home to the Mahama camp. Hosting refugees is part of MINEMA's work.
Worked example 1: refugees in the census
The 2022 census counted 13,246,394 people in Rwanda, including 107,300 refugees, and 50.4% of the refugees lived in Kirehe District. (a) What percentage of Rwanda's population were refugees? (b) About how many refugees lived in Kirehe?
Answer. (a) About 0.8%, fewer than one person in a hundred. (b) About 54,000 refugees, most of them in Mahama camp. A small share nationally can be a large number for one district.
Important
Case study: the Ruzagayura famine, 1943–44
In 1943 several long dry spells ruined harvests across Ruanda-Urundi (today's Rwanda and Burundi). Drought alone might have caused hardship; what turned it into a famine were human decisions. It was the Second World War, and the Belgian colonial authorities kept sending farm produce to the Belgian Congo for the war effort. Between October 1943 and December 1944, between 36,000 and 50,000 people died of hunger, and several hundred thousand left for the Belgian Congo and Uganda. King Mutara III Rudahigwa sent aid to the worst-hit areas. The name Ruzagayura is still remembered. The lesson for geographers: a drought is a natural hazard, but a famine is largely human-made.
Road accidents are caused by speeding, drunk or tired drivers, badly maintained vehicles, overloading, and wet, steep or winding roads. Mining accidents happen when pits collapse or slopes slide: in May 2023, heavy rain caused a landslide at a mine in North Kivu, DR Congo, that killed at least six people and left dozens of miners missing. Fires start from faulty electrical wiring, cooking and candles, and spread fast in crowded markets and homes. Prevention: speed limits and their enforcement, helmets and seat belts, safe vehicles, road-safety teaching; licensed mines with safe slopes and supports; safe wiring, fire extinguishers and fire exits.
| Hazard | Main causes | Main effects | Prevention and preparation |
|---|---|---|---|
| Earthquake | Movement on faults, as in the rift under Lake Kivu | Collapsed buildings, deaths and injuries, landslides, broken roads and pipes | Reinforced buildings, safe siting, drills ("drop, cover, hold on") |
| Volcanic eruption | Magma rising through thin, cracked crust (Nyiragongo) | Lava destroys homes and roads; ash; toxic gas; earthquakes | Monitoring, warnings, evacuation plans, no building in lava paths |
| Landslide | Heavy rain on steep, bare or cut slopes; earthquakes | Buried homes, roads and farms; deaths; muddy rivers | Terraces, trees and grass, drains, relocation from high-risk zones |
| Flood | Heavy or long rain, steep slopes, cleared land, building on flood plains | Deaths, destroyed homes, bridges and crops, disease | Forecasts and warnings, protecting wetlands, drains, no building on flood plains |
| Drought | Rains late, short or failed | Crop failure, hunger, dry wells, dead livestock, migration | Irrigation, rainwater harvesting, drought-tolerant crops, food storage |
| Strong winds | Thunderstorms and gusts in the rainy seasons | Roofs blown off, crops flattened, trees and power lines down | Tie down roofs, windbreak trees, shelter indoors, lightning conductors |
| Epidemic | Germs spread by water, mosquitoes, air or contact; crowding; poor sanitation | Illness and deaths; health services overwhelmed; lost work and school | Clean water, sanitation, vaccination, early detection, tracing, protecting health workers |
| War | Conflict over power, land or resources; hatred and division | Deaths, destruction, refugees, hunger, disease, land mines | Dialogue, justice, unity, regional cooperation, education for peace |
| Famine | Drought or crop disease made worse by war, poverty and poor decisions | Hunger, deaths, migration | Early warning, food reserves, fair distribution, peace |
| Accident | Human error, poor maintenance, unsafe roads, mines and wiring | Deaths, injuries, loss of property | Rules and enforcement, safety equipment, training |
Rwanda's Ministry in charge of Emergency Management (MINEMA) leads the country's work on disasters and refugee affairs. Its vision is "to build a disaster resilient nation". It writes the national disaster policies, coordinates the ministries, districts and partners that act in an emergency, raises the alarm, and educates the public so that preparing for disasters becomes a habit. Meteo Rwanda supplies the forecasts on which warnings are based.
Figure 1. An early warning is only useful if it reaches people in time and they know what to do. Drawn by Ganzaa.
Important
Case study: preparing before the rains, 2026
The seasonal forecast for the September–December 2026 rains warned of possible above-average rain linked to El Niño: between 300 and 1,000 mm, against a long-term average of 279 to 962 mm. MINEMA did not wait. The Umuganda of 29 August 2026 was dedicated to disaster prevention across the country: residents, local leaders, MINEMA staff and the security organs tightened roofs, cleared drainage channels, strengthened anti-erosion ditches and reinforced weak homes. Families in high-risk zones were urged to move before the rains, and people were warned not to shelter under trees in thunderstorms. As a MINEMA director told residents: "Preventing disasters is everyone's responsibility."
Worked example 2: how much wetter than normal?
The 2026 outlook gave up to 1,000 mm of rain where the long-term average reaches 962 mm, and at least 300 mm where the average is 279 mm. Find the percentage above average at each end.
Interpretation. The expected rain is 4% to 7.5% above average. That sounds small, but after a wet season the ground is already soaked, and a few extra heavy storms are enough to trigger floods and landslides. Warnings aim at the extreme nights, not the average.
Warning
Prevention is not the same as response. Response (rescue, shelter, food) happens after a disaster. Prevention and preparation (terraces, strong buildings, warnings, drills, moving families) happen before. When a question asks how to "prevent" or "reduce" a hazard's effects, answers such as "give food to victims" earn little.
ShakeOut Earthquake Drill: Drop, Cover and Hold On, by FEMA (under 1 min). Practise the three steps with your class; they are the right response in western Rwanda too.
Your school is on a slope in a district with heavy rain and occasional earthquakes. Draw up a five-point safety plan for the school, and decide which point matters most. Justify your choice using the idea of hazard, vulnerability and capacity.
Tip
Before, during, after. Organise any "managing hazards" answer in three parts: before (prevent and prepare), during (warn, evacuate, rescue) and after (shelter, rebuild safer, learn). Name MINEMA and a Rwandan case.
Practice
Remember
Further reading
Books and resources for this unit
Sources and credits
The lesson text, flowchart, table, worked examples and practice are written by Ganzaa.
This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.
