Oil Spills in U.S. Coastal Waters: Background, Governance, and Issues for Congress [Updated August 23, 2007] [open pdf - 221KB]
"During the past two decades, while U.S. oil imports and consumption have steadily risen, oil spill incidents and the volume of oil spilled have not followed a similar course. In general, the annual number and volume of oil spills have shown declines-in some cases, dramatic declines. The 1989 Exxon Valdez spill in Alaskan waters played a large role in stimulating actions that contributed to this trend, particularly the decrease in the annual spill volumes. The Exxon Valdez spill highlighted the need for stronger legislation, inflamed public sentiment, and spurred Congress to enact comprehensive oil spill legislation, resulting in the Oil Pollution Act of 1990 (P.L. 101-380). This law expanded and clarified the authority of the federal government and created new oil spill prevention and preparedness requirements. Moreover, the 1990 legislation strengthened existing liability provisions, providing a greater deterrent against spills. After 1990, spill volume from oil tankers, the vessels that carry and have spilled the most oil, decreased significantly. Considering that U.S. oil consumption and oil imports have steadily increased, the trend of declining spill incidents and volume in past years is noteworthy. Yet, recent annual data indicate that the overall decline of annual spill events may have stopped. Both consumption and imports are projected to maintain upward movement, and the United States is expected to increase the proportion of its imported oil. More oil-carrying vessels will be entering U.S. waters, and a higher percentage of transported oil will likely travel by vessel."
CRS Report for Congress, RL33705