Lake Mead's water level has fallen significantly during the past year and will continue falling into early 2004.
The lake currently is 1,162 feet above sea level.
"Lake Mead is a fluctuating reservoir, so it goes up and down depending on inflow and what is needed in the Colorado River system in the lower states," said Gary Warshefski, assistant superintendent of the Lake Mead National Recreation Area.
"Four years ago, Lake Mead was at one of its highest levels at 1,197 feet above sea level.
It has gone down 35 feet in the last two years and most of that fall has occurred in the last 10 months."
A lack of rain and snow in watershed areas at the headwaters of the Colorado River in Wyoming and Colorado is largely responsible for the dwindling level of Lake Mead, said Steve Leon, public affairs specialist with the Bureau of Reclamation.
The level will continue to decrease, according to projections by bureau hydrologists.
"From October 2002 through September 2003, the level of the lake will vary from 1,159.57 feet to 1,145.2 feet," Leon said.
"Between January and April 2004, which is as far as we're projecting right now, it will continue to hover in the mid 1140s."
The elevation at Lake Mohave is more stable.
Information from the Bureau of Reclamation projected the level of Lake Mohave at 644 feet Wednesday.
It is expected to drop to 642.7 feet during the week of June 17-23.
"Water released from Lake Mead is keeping Lake Mohave within its normal range," Warshefski said.
"The problem we have in managing the park is that the Bureau of Reclamation has been releasing more water from Lake Mead than is coming into it, so we're seeing a water loss at the rate of a foot per week.
That has been going on for three months and is scheduled to continue through the end of June when we will be at a 30-year low of 1,158 feet."
In September, that level will begin to increase as peak water demand for irrigation ends, Leon said.
But the increase will only be about 18 inches and, barring a heavy monsoon season, the drought will further reduce the level into winter and spring.
"We're going to need several years of good precipitation in the upper (Colorado River) basin to get back to normal," Warshefski said.
"Even in a normal (rainfall) year, the Bureau of Reclamation projects that next year Lake Mead will continue to fall another 12-14 feet.
The reason is that everything is so dry in Colorado and Utah that whatever precipitation they get in the near future will be soaked up by dry plants and soil, so there will be a minimal amount of runoff."