Who Loses Water When the Reservoir Is at 24%?
The Mokala Basin has three users. The Phoenix Mine, which earns 62% of the country's export revenue and employs 4,100 people, holds a water right of 18 million m³ a year. Downstream, 2,300 smallholder farmers irrigate 1,900 hectares of maize and vegetables, using about 11 million m³; most earn under P30,000 a year. The town of Mokala, population 71,000, draws from the same reservoir, which is at 24% of capacity after two failed rainy seasons. A new water accountancy study finds the reservoir can safely yield 26 million m³ a year, while current allocations total 34 million m³. The environmental reserve - the flow needed to keep the river and its floodplain alive - has never been quantified or enforced. The water authority proposes cutting farmers' allocations by 40%, leaving the mine's right untouched, and postponing the reserve. Farmers' unions have threatened to block the main road.
1. Evaluate the water authority's proposal using sustainability, efficiency and equity criteria. What is your recommendation?
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Sustainability. A 40% cut to farmers takes 11 down to 6.6 million m³, a saving of 4.4. Total use then becomes 18 + 6.6 + town demand, still above the 26 million m³ safe yield, and the reserve is still zero. The proposal therefore fails its own environmental test: it does not close the gap, it only delays the shortage.
Efficiency. The mine's value added per cubic metre is far higher than maize, so economic logic gives it priority. But the mine holds 53% of all allocations, and part of that water is used for low-value purposes such as dust suppression and ore washing, where recycling could cut demand by 15-20% without touching output. Efficiency argues for cutting the lowest-value uses first, whoever holds them.
Equity and enforceability. Farmers bear 100% of the adjustment, lose around 40% of income, receive no compensation, and have no legal route to challenge the decision. The predictable result is illegal abstraction and blockade, which destroys the plan's credibility and the authority's data.
Recommendation. Reject the proposal as presented. Require the mine to submit a water-recycling plan cutting its take by 10-15% within two years; cut farm allocations progressively with drought triggers and compensation for verified losses; define and enforce a reserve of at least 2 million m³; and meter all three users before the next season.
2. The water authority says the decision is technical and should be left to engineers. Explain why a decision-making process is needed, and set out what that process should include.
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The decision is not purely technical because the safe yield fixes a total but not a distribution. Any choice among users is a value judgement about whose losses count, and engineers have no special competence in that. Two further reasons: the authority is itself a party with an interest in avoiding conflict with the country's largest export earner, and a decision that users regard as unfair will not be complied with, which makes it technically unenforceable.
A defensible process would include:
- Published data. Safe yield, allocation registers, metering records and the reserve calculation available to all users.
- A stated hierarchy of use debated and adopted in advance - domestic water first, then the reserve, then economic use ranked by value per cubic metre.
- Negotiated adjustment with compensation, rather than announcement, including a drought-trigger schedule that everyone can plan around.
- Independent review of the mine's recycling plan and of farm water efficiency.
- A route to challenge decisions, so disputes go to a tribunal rather than to a road blockade.
Legitimacy is not decoration: it is the mechanism by which a water allocation actually holds in a dry year.
3. Would charging all users the full economic price of water solve the problem? Discuss.
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Pricing helps but only under conditions, and alone it can make things worse.
Where it works. A volumetric charge gives every user a reason to reduce waste, and it ranks users by willingness to pay, which usually moves water towards higher-value use. It also raises revenue for leak repair and metering, which are the cheapest sources of new supply.
Where it fails here. Willingness to pay reflects wealth, not value: the mine can outbid 2,300 smallholders for every cubic metre and would then hold the entire basin. Farmers earning under P30,000 cannot pay an economic price without losing the crop entirely, so a pure market converts a water allocation into a land-abandonment policy. The environmental reserve has no purchaser at all and would be priced out. And in a basin with no working meters, a price is unenforceable.
The design that would help. A tiered tariff with a lifeline block for domestic and smallholder use, a hard cap on each user's volume regardless of payment, revenue earmarked for efficiency investment, and the reserve allocated administratively before pricing begins. Price is then a tool within an allocation system, not a substitute for one. Treating the market as the answer simply changes who decides, from a public authority to whoever holds the largest bank balance.