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Readers should note that the spill data for the years 1969 through 1972 is presented here in tabular form and is cumulative for each year. Individual incidents can neither be confirmed nor can the data be statistically manipulated. Oil spill statistics are presented in both graphic and tabular formats for each of the years 1973 through 2001. Discharges of chemicals and other substances (garbage, sewage, etc.) are presented in tabular form only, with separate tables for liquids (gallons) and solids (pounds). Liquid spills whose reported volume was less than one gallon were rounded to one gallon for this report. All spill volumes were converted to either gallons or pounds, irrespective of the original units (barrels, tons, etc.) entered into the database. Data tables for each year, are categorized and presented in the following order: oil spills (measured in gallons), liquid chemical spills (measured in gallons), non-liquid chemical spills (measured in pounds), other liquid spills (measured in gallons) and other non-liquid spills (measured in pounds). Oil spill statistics for each year are presented in tabular format at the beginning of each section and include the following information: total number of spills and total volume in each category; mean (average), median and maximum spill size; and percentages. The tables are described below and appear in the order presented:
- Spill Size
- spills are sorted into nine, separate volume ranges (1-100 gallons, 101-1,000 gallons, 1,001-3,000 gallons, 3,001-5,000 gallons, ..., 100,001-1,000,000 gallons, over 1,000,000 gallons).
- Waterbody
- 223 individual waterbodies (Delaware River, San Francisco Bay, Lower Mississippi River, Gulf of Mexico, Bayou La Batre, etc.) were sorted into nine categories that include the Atlantic and Pacific oceans, Gulf of Mexico, Great Lakes, rivers and canals, harbors, bays and sounds, lakes, and other. In past publications, many rivers, harbors, and tributaries were coded so that spills in those waterbodies were represented as having occurred in the ocean or gulf to which they were connected. This is no longer the case. Waterbodies included in each of these categories are listed in Appendix A.
- Location
- categories include internal/headlands (rivers, harbors, intercoastal waterways, etc.), coastal (territorial waters (0-3 miles)), contiguous zone (3-12 miles), ocean (12-200 miles), ocean general, and other.
- Major source and detailed source
- 53 listed sources in the detailed source table are sorted into seven broad categories in the major source table. Major sources include tankships, tank barges, all other vessels, facilities, pipelines, all other non-vessel sources, and unknown or not elsewhere classified (NEC). Because the detailed sources are too numerous to represent graphically, only the major source categories are presented graphically.
- Vessel/Facility Operation (through 1993 only).
- 41 individual, coded operations were sorted into ten categories that were reported as ongoing operations at the time of the spill. They include: pumping bilges, bunkering (refueling), tanker/facility operation, cargo transfer/receiving, movement in congested waterway, lightering, underway/transporting, pipeline, other known operation, or unknown operation. Operations data represents information that may be useful for oil transportation risk assessment. Specific operations within these categories are also listed in Appendix A.
After 1993, this table is not provided, because of changes in the data collection system.
- Oil Type
- 174 different petroleum and non-petroleum oils were sorted into the following six general categories: crude oils, heavy fuel oils (#4, #5, & #6 fuel oils), intermediate fuel oils (diesels, light crudes,) gasoline (automotive and aviation), other petroleum oils (gas-oil, asphalt, etc.), and non-petroleum oils (vegetable oils, coconut oil, etc.). The substances within each of these categories are also listed in Appendix A.
- Cause, (through 1992 only).
- though each spill has a separate cause, and though the large majority of spills are believed to result from human error, this table reflects the limited number of causal choices that have been included in this database. There is useful information represented in this table but it can also be misleading. For example, structural failure may stem from a collision or grounding, but neither the collision, grounding, or the events preceding the spill were recordable in the database prior to 1992. After 1992, this table is not provided, because of changes in the data collection system.
- Month
the spill incident occurred.
- Coast Guard District
- See a Map of Coast Guard Districts.
- State
where the spill incident occurred. Spills beyond U. S. state waters are listed under "other".
NON-OIL TABLES: Chemical Spills and Other Spills are represented by identical tables with the exception of "Oil Type". Unlike oil which is easily sorted into several discreet categories, chemicals and other substances are unique, not easily categorized, and too numerous to list individually. In all but a handful of cases, year-end statistics (percentages) precisely reflect column totals. In those instances where this is not the case (99.9% vs. 100%), the unavoidable differences are attributable to "rounding" in the computer scripts that created the tables and could not be eliminated within the existing software.
Graphics: At the conclusion of each annual section are graphic representations of the tabulated oil spill statistics presented by number and volume of spills that occurred. The graphics appear in the following order: Oil Type, Waterbody, Location, Major Source, Operation (through 1993). Appendix A contains the list of MSMS codes represented in these graphics.
The data for each of the years listed below are in separate reports and can be viewed by selecting the desired link. The files are stored in the Adobe "pdf" format and must be opened with the Adobe Acrobat File Viewer, which is available from the Adobe internet site. Also, the 2000 and 2001 reports, without graphs, are provided as a text/HTML file. |
