I spent 8 years flood-proofing a city. Capital markets are running out of time to take El Niño seriously

Federal forecasters put the odds of a strong El Niño this winter at two in three. The bigger story isn't the weather.

Federal forecasters put the odds of a strong El Niño this winter at roughly two in three, and the odds of one matching or exceeding the record 2015 event at better than one in three. That forecast is worth taking seriously. But the bigger story is that resilience infrastructure has quietly become a distinct investment category — and capital markets have been slow to treat it that way. A strong El Niño will make ignoring that gap even more expensive.

I served as mayor of Hoboken for eight years. The lesson I took from that job: the financial case for resilience is almost always stronger than people assume. When a city manages physical risk well, it protects property values, the tax base, business continuity, and credit quality at the same time. When it does not, all four take a hit at once.

In Hoboken, we built ResilienCity Park on the site of a former chemical plant. The park combines green space with underground stormwater detention systems that can hold roughly two million gallons during a major rain event. It is one of several projects the city pursued under the broader Rebuild by Design effort following Superstorm Sandy. The result was less flooding, faster recovery after storms, and fewer disruptions for residents and businesses. During my tenure, S&P Global Ratings repeatedly affirmed Hoboken’s AA+ credit rating, citing the city’s resilience investments and its approach to long-term environmental risk.

The demand for this kind of work has grown well beyond what any city, state, or federal program can fund alone. Boston Consulting Group has projected that annual demand for resilience-focused investment could reach $3 trillion by 2030, with the cost of inaction up to 15 times more expensive. A survey BCG ran with the Rockefeller Foundation found that more than four in ten institutional investors across the major markets now identify adaptation and resilience as a theme they want exposure to. Rating agencies, including Moody’s, are incorporating physical climate risk into their analyses. These are the ingredients of a market, but not yet the structures, standards, and interplay that would make it function like one.

The clearer way to think about this category is by physical sector, not as a single bucket called “climate adaptation.” Flood and stormwater infrastructure — including flood protection barriers, detention systems, raised roads, green stormwater capture — is the most familiar piece, and the one I worked on most directly in Hoboken. Grid and energy hardening is a second category, covering buried transmission, microgrids, substation flood protection, and wildfire-resistant utility design. Water supply and treatment is a third, including drought-resilient supply, leak reduction, and systems built for the rainfall patterns of the next thirty years rather than the last thirty. Wildfire defense and forest management is a fourth, increasingly relevant well beyond the Western states. Coastal and transportation adaptation is a fifth, covering ports, airports, rail corridors, and highways that need to keep functioning through more extreme conditions than they were originally engineered for. Each has its own engineering profile, regulatory environment, and set of public and private actors. Treating them as one undifferentiated category is part of why investor interest has been slower to translate into investor activity.

The structural problem behind that lag is that the dividend from resilience infrastructure does not look like a toll road or a wind farm. Its returns come largely in the form of avoided losses — damage that did not happen, business interruption that was prevented, revenues that were preserved — and those benefits accrue across municipal budgets, insurance balance sheets, small businesses, and private property at the same time. Investor interest is real and growing. What’s been slower to develop is the middle of the pipeline: projects engineered, permitted, and structured to the point where institutional capital can actually underwrite them. A pension fund or insurance allocator cannot buy a concept; it needs a definitive revenue projection, a contract structure, and enough scale to be worth the diligence. Blended capital arrangements, resilience-linked municipal debt, environmental impact bonds, and well-designed public-private partnerships are all moving from concept to practice. What is missing is execution at scale on the project-preparation side.

The most reasonable objection to this view is that resilience returns are too diffuse to underwrite, that avoided losses do not show up in a project’s revenue line the way tolls or tariffs do. That objection is proving to have less force with time. Insurers are pricing physical risk more aggressively, rating agencies are doing the same with municipal credit, and the discount applied to vulnerable assets is now visible in markets where it used to be invisible. The returns to resilience are increasingly easy to see because the losses from its absence are increasingly easy to count.

A strong El Niño will pull all of this forward. Floods, droughts, fires, and grid strain that might have been spread across several normal years tend to arrive together during an event like the one being forecast. The places and balance sheets that have already invested in resilience will fare better. The ones that have not will pay the bill in real time. From where I sit, after eight years running a small city that flooded badly and then learned how to stop flooding, the case is straightforward. Resilience infrastructure is a real category, with real sectors and real financial logic behind it. Capital markets that engage with it seriously, sector by sector, will be in a better position than those that continue to treat climate adaptation as someone else’s problem. A strong El Niño will only make that case harder to ignore.

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