Rapid Economic Assessment of Flood-control Failure along the Rio Grande: A Case Study

Abstract

Recent flood events along the international border between the USA and Mexico resulted in significant economic damage and loss of human life. The International Boundary and Water Commission, the agency responsible for monitoring US–Mexican flood control levees, had requested funding for maintenance and improvement of these levees. However, the Office of Management and Budget requires agencies to provide benefits or in this case avoided loss estimates to justify the budget request. Due to severe time constraints in the budgetary process there was a need for a rapid assessment of the potential economic impacts from a failure of this ageing flood-control infrastructure. The economic losses avoided by four major flood-control projects on the Rio Grande were estimated using an innovative combination of satellite imagery, geographic information systems, and economic methods. The control projects apply to about 547 km (340 miles) of levees from Caballo Reservoir in New Mexico to Brownsville, Texas, and include several million people, extensive industry, and agricultural production. High resolution imagery was used to identify and quantify potential flood inundation areas, types of land use, and impacts of flood-control infrastructure failure. Value estimates of residential, industrial, and commercial property, and agricultural production at risk were developed from property assessment data, crop enterprise budgets, census data, and community leaders. Damage factors accounting for flood inundation levels and building contents were then used to develop gross economic losses avoided by flood-control infrastructure for each of the different property and land use types in each project area. The baseline analysis indicates that the four projects cumulatively prevent one time losses of US$322.9 million in flood-control protection.