Sixty Million for Flood Protection
A coastal county of 180,000 people has a fixed $60 million to spend on flood protection and must choose one option. Option A is a levee around the low-lying Harbor District, home to 9,000 residents and 40 percent of county jobs; it costs $60 million and protects against a 50-year flood. Option B is elevating 1,200 homes in the North Flats at $35,000 each (about $42 million) plus $18 million of wetland restoration that absorbs storm surge; together they protect about 15,000 residents against a 25-year flood. Option C is buying out 400 repeatedly flooded homes at $150,000 each and turning the land into parkland. Regional projections show the Harbor District flooding roughly twice as often by 2060, while restored wetlands would keep the North Flats from worsening. The county's poorest census tracts are in the North Flats.
1. Which option would you recommend, and on what criteria? Show the trade-offs you weighed.
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Use explicit criteria: people protected per dollar, equity, durability under sea-level rise, economic disruption, and reversibility.
- Option A protects 9,000 residents plus 40 percent of jobs, roughly $6,700 per resident. But it protects a place projected to flood twice as often by 2060, and levees fail catastrophically when overtopped: the residual risk is concentrated and severe. Maintenance costs are not in the $60 million.
- Option B protects 15,000 residents for the same money, about $4,000 per resident, and the wetlands improve with time instead of degrading. Weaknesses: only 25-year protection, and elevating a house does nothing for renters.
- Option C permanently removes risk for 400 households and creates public land, but protects the fewest people and relocates a neighborhood.
A defensible recommendation is Option B, on people-per-dollar, long-term fit, and co-benefits. A defensible alternative is a hybrid that protects the harbor's jobs while funding North Flats elevation, if matching funds exist. What matters is that the answer names the trade-off: B protects more people but leaves the job center exposed, while A protects the economy but doubles down on the riskiest ground.
2. Whichever option you chose, it has an equity problem. Identify it and propose a fix within the same $60 million.
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Every option leaves someone out, and the answer should say who.
- If B: elevation grants go to homeowners. Renters, often the poorest residents, receive nothing, and landlords who elevate may raise rents on newly protected property. Fix: reserve part of the $60 million for rental relocation assistance, and require landlords who accept elevation funds to accept a rent limit or a lease term.
- If A: the harbor's jobs are protected, but the poorest tracts in the North Flats get nothing, and improved flood safety can raise harbor property values and push out current renters.
- If C: buyouts help owners who receive pre-flood value, but 400 households are displaced and must find housing nearby, which is scarce and rising in price.
A strong answer names the excluded group, explains the mechanism (who receives the benefit, who bears the cost), and proposes a specific use of the same budget rather than just saying the county should be fair.
3. What information would change your recommendation?
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Recommendations here rest on assumptions, and naming them is the point.
- Time horizon. Is 2060 within the county's planning horizon? If the county plans in 20-year windows, A's deteriorating protection matters less than if it plans for a century.
- Maintenance costs. The levee's annual upkeep may consume money that could protect the North Flats.
- Tenure. How many North Flats residents are renters? The higher the share, the weaker elevation-only protection becomes.
- Matching funds. State or federal money could make a hybrid affordable and change the ranking entirely.
- Buyout terms. Are buyouts voluntary, and priced at pre-flood value? Forced buyouts at depressed values would be a serious equity problem.
- Population trend. A growing North Flats raises the value of B; a shrinking one lowers it.
A good answer says what evidence would flip the decision, not just what evidence would support it.