In September 2013, an unprecedented rainfall event occurred along Colorado’s Front Range of the Rocky Mountains, resulting in catastrophic flooding that impacted 18 Colorado counties and 132 jurisdictions. After an event of this magnitude, FEMA would typically conduct a loss avoidance study (LAS) to assess the cost-effectiveness of mitigation measures such as acquisition of properties in the floodplain and implementing flood control measures. However, the September 2013 floods provided a unique opportunity to evaluate the losses avoided through a non-traditional approach. While the Community Rating System (CRS) concepts of adopting higher regulatory standards and floodplain management principles are advocated as best practices, there is little empirical data to demonstrate the return on investment for these regulatory or policy actions. The goal of the study was to quantify these benefits and demonstrate what types of regulations and policies could have the most substantial impact on reducing future damages.
This study evaluated scenarios including regulating freeboard, restricting building of residences and critical facilities in regulatory floodplains, and controlling development in erosion zones. In addition to regulations, the study investigated how the adoption of regulations over time affected losses, and how CRS scores affected NFIP claims and policies.
The conclusive results of this study continue to demonstrate that higher floodplain regulations result in benefits reflected by a reduction in flood-related losses. Furthermore, jurisdictions not implementing higher regulatory standards may observe substantial increases in future flood losses. This information, in addition to traditional Executive Summary mitigation actions, can be used by floodplain managers and community officials to support the case for implementing higher regulatory standards for flood mitigation and protection.