The Marina and the Mangroves
Brightwater is a settlement of 1,200 people on a Family Island. A developer proposes a 60-slip marina and 40-room hotel, promising 90 construction jobs and 25 permanent jobs. The plan requires dredging four hectares of red mangrove and building a channel through the reef. The mangroves currently buffer the shoreline from storm surge, and local fishers say they are a nursery for snapper and queen conch. After the last hurricane, the beach near the site lost about three metres of sand. The settlement's piped water comes from a shallow freshwater lens close to the proposed channel; the environmental assessment warns that dredging could let salt water into it. The developer has offered to fund a seawall and a scholarship programme. The government must approve, reject, or approve with conditions.
1. Identify the main trade-offs in the proposal and explain which risks are most serious.
Read the worked answer
The proposal trades long-term environmental services for short-term construction activity. The 90 construction jobs are temporary; only 25 jobs are permanent. The mangrove loss is permanent unless restoration succeeds, and mangroves provide storm-surge protection, fish nursery habitat and shoreline stability. The freshwater lens is the most serious risk because saltwater intrusion could contaminate the settlement's drinking water and is costly or impossible to reverse. A seawall may reduce wave energy but cannot replace nursery habitat, and a scholarship is compensation, not mitigation. The beach erosion of three metres suggests the shoreline is already under stress. A strong answer would rank the risks: water supply and irreversible mangrove damage first, fisheries second, and job gains third, because the jobs are modest and reversible while the ecological losses are long-term. The precautionary principle supports requiring proof that dredging will not salinise the lens before approval.
2. Recommend a decision and two conditions, explaining how each condition addresses a specific risk.
Read the worked answer
Recommend approval only if the project is redesigned, because outright rejection may forgo needed jobs but unconditional approval accepts unacceptable risks. Condition 1: reduce the dredged area and relocate the channel away from the mangrove and freshwater lens; an independent hydrologist must monitor salinity for five years, with the developer posting a bond. This addresses the most serious risk, saltwater intrusion, by avoiding the lens and making the developer pay for monitoring and remediation. Condition 2: require no net loss of mangrove habitat, with a 2:1 replanting ratio and five-year survival targets, plus a funding escrow. This addresses storm protection and fisheries nursery loss, though replanting is not a perfect substitute. Also require local hiring targets and a reef survey before construction. If the developer refuses independent monitoring or the bond, reject the project, because the conditions are what make approval defensible.