WHAT’S AWASH IN THE WASH? Combating Water Quality Problems in the Las Vegas Wash This issue of River Report discusses the problems with Las Vegas Wash water quality issues related to perchlorate contamination, the primary ingredient in rocket fuel that has been shown to cause thyroid problems in humans, sediment erosion and the effect on Lake Mead – and the potential effect on other Colorado River water users downstream. It also details what steps are being taken to remedy these problems.