As the Colorado River winds through the Colorado Plateau's soft sedimentary strata, it picks up a tremendous amount of sediment. This sediment - which once left the river's waters so muddy that Spanish explorers christened it El Rio Colorado "the reddish river" - is a vital component to the unique ecosystems of the river. However, with the construction of the Hoover and Glen Canyon dams, which trap the sediment, the once-turbid waters have become a dazzling blue-green, signaling major changes with serious implications for the health of the river's native ecosystems.