An evaluation answer has three parts: what each option gives, what each option costs, and a final judgement for this case. The judgement is what turns a list into an answer.
This lesson is part of river processes and sustainable management. It builds on interpreting a hydrograph, because the case usually gives a flood risk to manage.
What does a balanced case look like?
A balanced case shows benefits and drawbacks for each option, so that no option wins by default. You must read the evidence and decide.
Here is an original, invented case. The town of Lembah Jernih lies on a low floodplain and its river overflows in heavy rain.
| Option | Given benefit | Given cost |
|---|---|---|
| Concrete embankment along 4 km of bank | Protects 600 houses from the river | High build cost, blocks natural flooding of the wetland downstream |
| Flood-retention pond upstream | Stores water and lowers the peak | Needs 12 hectares of farmland |
| Replanting the upper catchment | Slows runoff, low cost, supports wildlife | Takes years to work, protects less in the next storm |
Worked example: from table to judgement
Step 1, benefit. The embankment gives the strongest immediate protection, because it covers 600 houses right now.
Step 2, cost. It is the most expensive, and it stops the wetland from receiving floodwater, which harms habitat. The pond removes 12 hectares of farmland from farmers. Replanting protects the least in the short term.
Step 3, judgement. The town needs protection soon, and the pond takes only 12 hectares of farmland, so the retention pond with replanting is the better package. The pond lowers the peak in the next storm, and replanting adds slow, long-term benefit at low cost. The embankment is less suitable here because its cost and damage to the wetland outweigh its speed.
The answer commits to a choice and cites figures from the case.
The mistake that costs marks
Weak answers list methods from memory, such as “dams, embankments, afforestation”, and stop. They ignore the case and never say which is best.
| List answer | Evaluative answer |
|---|---|
| “An embankment protects houses.” | “An embankment protects 600 houses, but its high cost and loss of wetland flooding make it less suitable.” |
| “Replanting is good for the environment.” | “Replanting is cheap, but it works slowly, so it should support a measure that helps sooner.” |
Check yourself
In a new invented case, a fishing village can choose between a sea-facing wall that costs RM8 million and restoring mangroves that cost RM1 million but grow for several years. Give a one-sentence judgement and name one limit of your choice.
Answer
A sample judgement: mangrove restoration suits the village better because it costs one-eighth of the wall and protects the coast while supporting fish breeding.
Limit: mangroves take years to mature, so the village stays exposed in the meantime. A careful answer adds that the wall might be chosen only if the danger is immediate.
What to study next
Test the whole cluster with the river processes practice set, then log any weak sentences in the mistake log and paper-error review.
If you want a teacher to help you commit to a judgement and defend it, see online one-to-one Geography tuition.