Approaches for Ecosystem Services Valuation for the Gulf of Mexico After the Deepwater Horizon Oil Spill: Interim Report

The DWH oil spill immediately triggered a process under the U.S. Oil Pollution Act of 1990 (OPA) to determine the extent and severity of the "injury" (defined as an observable or measurable adverse change in a natural resource or impairment of a natural resource service) to the public trust, known as the Natural Resources Damage Assessment (NRDA). The assessment, undertaken by the trustees (designated technical experts who act on behalf of the public and who are tasked with assessing the nature and extent of site-related contamination and impacts), requires: (1) quantifying the extent of damage; (2) developing, implementing, and monitoring restoration plans; and (3) seeking compensation for the costs of assessment and restoration from those deemed responsible for the injury.

This interim report provides options for expanding the current effort to include the analysis of ecosystem services to help address the unprecedented scale of this spill in U.S. waters and the challenges it presents to those charged with undertaking the damage assessment.