Like all dams, Glen Canyon traps sediment (silt), but because the Colorado is an especially muddy river, the dam has posed even more visible consequences for the river within the Grand Canyon. About 100 million US tons (90,700,000 metric tons) of sediment are trapped behind the dam annually, equal to about 30,000 dump truck loads per day. Because of the dam, sediment deposited by the Colorado and its tributaries is slowly filling up the canyon, and projections put the useful life of the reservoir at 300 to 700 years. If no action is taken such as dredging or sediment sluicing, in a few hundred years, sediment deposits will begin to build up at the foot of the dam and will gradually block the different outlets, reducing the dam's capacity to store and release water. Thus, it would become more difficult to maintain the required release of below the dam. The Colorado River would reduce to a trickle in dry seasons as it naturally did before the dam was built, potentially compromising the water supply of the Lower Basin states.