Over the last 50 years, consumption of diesel fuel has risen dramatically in California. Diesel exhaust is known to cause cancer, is associated with asthma, and is a major source of smog. Although our increased use of diesel results from several factors, the main reason is the growing use of diesel trucks to transport goods around the state. The absence of strict diesel regulations has encouraged Californians to rely increasingly on this dirty fuel despite its known hazards.
NRDC analysts looked at data on statewide consumption of diesel and other fuels from 1950 to 1999. Researchers also looked at vehicle diesel consumption in the Bay Area for 2000 (NRDC researchers could not find comparable data for the Bay Area for 1950 to 1999), as well as projected consumption through 2020. Statewide, consumption of diesel increased twentyfold from 1950 to 1999; between 1980 and 1999 alone it doubled. Worse still, it's not only the absolute consumption of diesel that grew: diesel consumption as a percentage of total fuel consumption also increased sharply -- from about 4 percent in 1950 to 15 percent in 1999. Here in the Bay Area, diesel consumption in 2000 amounted to some 452 million gallons, according to the California Department of Transportation, which projects a 31 percent increase in consumption by 2020.