Bacterial organisms were found in three areas of the Mescalero reservation in southern New Mexico and tribal members were being told to boil their drinking water. Residents in the Nogal Canyon area, the Silver Lake area and customers of the North Springs water system around tribal offices were urged to boil water until tests scheduled determine if the water is safe, said tribal sanitarian John Whitehead. Tests conducted June 19 in the Nogal Canyon and Silver Lake areas showed the presence of fecal coliform - bacteria usually associated with the presence of human or animal waste. "We have chlorinated and flushed the lines and will retest the lines," Whitehead said. He said about 1,000 people - more than one-quarter of the tribe's population - are affected by problems with the North Springs system. About two dozen people live in the Nogal Canyon area, while campers and others use the Silver Lake campground. Whitehead said he was not aware of any health problems resulting from the drinking water supply. Microbiological contaminates can cause diarrhea, cramps, nausea, jaundice, along with headaches and fatigue.