Physical Risk Only Becomes a Credit Problem When Governments Can't Manage It

By Matt Posner, Contributing Author for The Epicenter and Head of Public Finance for The Resiliency Company.

In the last year, Moody’s, S&P, and Fitch have all downgraded debt associated with Corpus Christi, Texas, citing concerns that include acute drought, deteriorating water supply, financial performance, and the city’s ability to execute a long-term water strategy. 

The actions have fueled a broader argument that Corpus Christi may foreshadow a wave of municipal credit deterioration as physical climate risks intensify.

But events since those downgrades complicate that interpretation. Heavy summer rainfall dramatically replenished Corpus Christi’s reservoirs, allowing the city to ease water restrictions and push back the immediate threat of a water emergency. The credit and governance problems, however, have not disappeared. City leaders remain divided over how to secure a long-term water supply, including whether to proceed with a nearly $1 billion desalination project.

While physical conditions can change quickly, the fiscal capacity, infrastructure decisions, and governance systems required to manage those conditions change much more slowly. 

Corpus Christi therefore offers a useful case study in climate as a force multiplier: Physical risk creates fiscal pressure, but how that pressure translates into municipal credit ultimately depends on how governments manage those risks.

This distinction is important not only for municipal leaders, but also for investors evaluating municipal debt. Investors need to distinguish between physical exposure itself and the financial capacity of a particular government or enterprise to manage that exposure. The relevant question is not simply, “How exposed is this place?” but, “How capable is this government of absorbing, financing, and reducing that exposure?”

The Broader Municipal Market and Why the Expected Wave of Downgrades Has Not Materialized

Treating all municipal credit as equally exposed obscures an important nuance: Physical risk can be concentrated in specific enterprise systems, such as water and power utilities, rather than affecting a government's general credit uniformly.

This is why the municipal market has consistently proved more resilient than expected. After the 2008 financial crisis, some financial analysts predicted widespread municipal distress, but those predictions did not materialize. There are several structural reasons why the municipal bond market tends to hold steady: 

• State and local governments maintain diverse revenue streams. Property taxes, sales taxes, fees, intergovernmental transfers, and enterprise revenues provide a level of diversification that buffers against localized shocks.
• Strong legal frameworks reinforce fiscal discipline. Balanced budget requirements, statutory lien protections, and conservative debt structures limit fiscal deterioration. Statutory liens, in particular, give bondholders a secured claim on pledged revenues that survives even municipal bankruptcy, providing a legal backstop that has no clean analog in climate risk itself.
• Active management remains central to credit quality. Municipal credit outcomes are heavily influenced by how governments respond to stress, rather than the presence of stress alone.

For these reasons, credit deterioration following disasters or other physical shocks has generally been targeted rather than systemic.

Consider the Los Angeles Department of Water and Power, which faced rating pressure following the 2025 wildfires. The utility’s exposure to physical risk and infrastructure liability created credit stress, yet the broader credit of Los Angeles did not experience a parallel downgrade.

Enterprise systems, like a water or power utility, can help contain risk within a discrete credit structure, but they can also concentrate it. For investors, understanding where physical risk sits within a government’s financial architecture may be as important as understanding the magnitude of the hazard itself.

Physical Risk Becomes Credit Risk Through Financial Decisions

Credit deterioration in the municipal market rarely stems from diffuse long-term risks alone. It is typically triggered by discrete decisions or structural imbalances such as a failed project, an overleveraged enterprise, or a mispriced derivative.

Historical examples illustrate this: Harrisburg, Pennsylvania, faced distress due to its incinerator financing. Jefferson County, Alabama, the most populous county in the state, got into trouble because of its sewer system debt and interest-rate swaps that backfired. The debt originated from a sewer system expansion required after the EPA accused the county of dumping raw sewage into nearby rivers. When it filed for bankruptcy in November 2011, it became the largest municipal bankruptcy in U.S. history.

Corpus Christi Shows How Structural Pressures Compound Into a Downgrade

Corpus Christi’s credit trajectory also reflects a convergence of structural pressures rather than a single exogenous shock. The city’s economic base is highly concentrated. Its role as a petrochemical and port hub creates both strength and volatility. Industrial expansion has driven growth, but it also ties fiscal performance to cyclical sectors and exposes the city to environmental and energy transition risks. Rating agencies have repeatedly flagged this concentration as a constraint on credit quality.

Enterprise risk plays an outsized role. Like many cities, Corpus Christi relies heavily on utility systems, particularly water and wastewater, as revenue-generating enterprises. These systems are capital-intensive, operationally complex, and increasingly exposed to climate variability and regulatory pressures. When these systems face stress, whether from infrastructure demands or rate-setting constraints, they can materially affect the broader credit profile.

Summer rainfall substantially improved Corpus Christi’s near-term water position, replenishing reservoirs and allowing the city to ease water restrictions. But rainfall did not resolve the underlying credit challenge. The city still must determine how to finance and deliver a reliable long-term water supply, while its City Council remains divided over the proposed Inner Harbor desalination project. Fitch subsequently joined Moody’s and S&P in downgrading the utility system, emphasizing weakened financial performance, water-supply constraints, and uncertainty surrounding the execution of new supply projects.

In effect, Corpus Christi’s physical-risk outlook improved faster than its credit outlook. A change in weather can alter the probability of near-term loss. But it cannot repair a balance sheet, build infrastructure, establish reserves, or resolve years of deferred capital decisions. Those are functions of financial management.

Physical risk is becoming increasingly relevant to municipal finance. Insurance markets are retrenching in some high-risk areas, infrastructure is becoming more expensive to protect and replace, and federal disaster support is becoming less predictable. But physical exposure does not translate mechanically into credit deterioration. Its impact is filtered through the fiscal capacity, financial policies, infrastructure systems, and management decisions of the government carrying that risk.

Climate Risk Is A Governance Stress Test

Corpus Christi suggests that the relevant unit of analysis for municipal credit is not physical risk alone, but a government’s financial capacity to manage it. A drought becomes a credit problem when water revenues fall, emergency expenditures rise, capital requirements accelerate, reserves prove inadequate, or political constraints prevent rates and investments from adjusting.

The hazard creates the pressure; the financial system determines how much of that pressure reaches the balance sheet.

That means one of the most consequential resilience investments a municipal government can make is improving its underlying financial capacity to absorb and respond to risk. Reserve adequacy, revenue flexibility, capital planning, enterprise governance, insurance strategy, and debt capacity are not peripheral to resilience—they are the mechanisms through which physical risk ultimately becomes, or does not become, a credit outcome.

The Government Finance Officers Association's work is especially relevant here: GFOA has long argued that reserves should be calibrated to risk rather than set at arbitrary levels. A physical-risk-informed reserve framework would link reserve levels to probabilistic risk modeling, scenario analysis, and explicit fiscal policy goals. 

Over the last year, The Resiliency Company has developed a way to take a reserve framework and apply a probabilistic model to the framework that any government can use to quantify natural hazard liabilities within their jurisdiction (request more info here about our RiskReserve Tool).

For governments, this requires a shift from treating physical risk primarily as an emergency-management or infrastructure issue to treating it as a financial-management issue. Governments should be able to estimate the potential fiscal losses associated with major hazards, understand how those losses compare with reserves and operating revenues, identify where risk is concentrated within enterprise systems and public assets, and evaluate whether mitigation investments improve that financial position.

The next phase of resilience finance must therefore move beyond identifying which communities face physical risk and focus on how governments manage it. That means translating physical risk into the language of municipal finance—projected losses, reserves, revenues, debt capacity, capital requirements, and operating budgets—so governments can make better decisions and markets can distinguish between risk that is present and risk that is financially unmanaged.

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