Work in Progress

A Flood of Construction: An Analysis of the Role of Levees in Urban Floodplain Development

with H. Allen Klaiber

The term “The levee effect”, the process by which the physical protection of vulnerable areas may actually increase exposure to damages, was coined in 1995 by geographer Graham Tobin, though the intuition behind the term dates back to at least 1945 in Gilbert White’s “Human Adjustment to Floods”. Still, the reality of this phenomenon is supported by little empirical evidence. In this paper, I present the first causal estimate of the impact of levee construction on residential development. Using the discrete construction of levees in southern Florida in response to the Flood Control Act of 1948, I employ an event study design and narrow spatial and temporal buffers and find that the construction of levees increased rates of urban development per year by over 100% in newly leveed areas. Results are robust to alternative buffer distance, fixed effects, and modeling frameworks. While concerns of external validity linger, these results fill critical policy analysis needs and inform regional planners of unintended consequences of investment in protective capital