49 



water entering the reaalning 205 ports Is thus not known. He have 

 conservatively estiaated the influence of bulkers, tankers, and general 

 cargo vessels arriving froa foreign ports in cargo (unacknowledged 

 ballast) and without cargo (acknowledged ballast) at these 205 ports by 

 assuaing that one-half (100) of these ports receives at least 10 percent 

 (239,400 HT) of the .average volume of the total acknowledged and 

 unacknowledged ballast water received at each of the 21 ports (2,394,000 

 HT). There are in addition aore than 25 other types of ocean-going 

 vessels in the foreign traffic that visit O.S. waters. We assuaed that 

 all of these reaaining vessels release at least 10 percent of the total 

 voluae of acknowledged and unacknowledged ballast as calculated for the 

 21 ports for bulkers, tankers, general cargo, and container ships; this 

 we assuae to be an underestimate. 



These estiaates indicate that approxiaately 58, OCX), 000 aetric tons, or 

 over 15,000,000,000 gallons of ballast water, are released every year in 

 O.S. waters by vessels froa foreign ports. This is about 42,(X)0,000 

 gallons per day, or over 1,700,000 gallons an hour. In biological teras 

 this aeans that over 28,000 gallons per ainute of exotic aquatic 

 organisBs are released in U.S. waters froa all over the world. 

 In tankers acknowledged ballast is highest at Los Angeles/Long Beach, 

 with a total of over 3.000,000 aetric tons (790,500,000 gallons) 

 arriving in 1991. Reaaining ports aaong the top five are New Orleans, 

 Houston/Galveston, Anchorage, and New Tork. In bulk cargo vessels 

 acknowledged ballast is highest at New Orleans, with a total of over 

 12,000,000 HT (3,160,000,000 gallons) of water arriving in 1991, 

 followed by Norfolk with over 9,000,000 HT (2,370,000,000 gallons) of 

 water. The top five sites receiving the largest voluaes of ballast 

 water froa general cargo traffic are New Orleans, Houston/Galveston, 

 Hiaai. Taapa. and Savannah. 

 On the Pacific coast Los Angeles/Long Beach and Tacoaa/Seattle are aaong 



