Q1. [5] deep thorough-understanding
Multi-purpose dams were envisioned as solutions to water scarcity, yet they have themselves become sources of new environmental and social problems. Justify this statement by discussing at least FOUR specific problems caused by large dams, and explain how each problem contradicts one of the original purposes for which dams were built.
Generated by claude-sonnet-4-6 · 2026-06-26 13:31 · grounding rag
Model Answer
Multi-purpose dams were built to solve problems like water scarcity, floods, and power shortage, but they have created new problems:
- Flood control defeated: Dams were built to control floods, but sedimentation in reservoirs has triggered floods. Big dams have mostly been unsuccessful in controlling floods during excessive rainfall.
- Ecological damage: Damming disrupts natural sediment flow, creating rockier stream beds and poor aquatic habitats. Dams fragment rivers, preventing aquatic fauna from migrating for spawning — contradicting the aim of supporting fish breeding.
- Soil degradation: Flood plains are deprived of silt (natural fertiliser) due to sedimentation in reservoirs, causing land degradation — harming the very agriculture dams were meant to support.
- Displacement and social problems: Large reservoirs submerge forests and existing settlements, displacing communities — contradicting the goal of improving livelihoods.
- Induced hazards: Dams have caused water-borne diseases, earthquakes, and soil salinisation due to excessive irrigation, worsening health and ecological conditions.
Source: Multi-Purpose River Projects and Integrated Water Resources Management, Chapter 3
---
Explanation
- Examiners expect four distinct problems, each linked to a contradicted original purpose — this earns full marks.
- Use textbook vocabulary: "sedimentation," "sediment flow," "aquatic fauna," "salinisation," "spawning."
- The contrast structure ("built to… but caused…") directly addresses "justify the statement" phrasing.
- Avoid writing a general essay; crisp numbered points score better in 5-mark answers.