An invasive mussel that has taken up residence in Lake Powell on the Colorado River is threatening Utah’s push to develop a $1.8 billion pipeline to deliver water to fast-growing areas. The Army Corps of Engineers has asked the state to provide a plan on how it will prevent the pipeline from transporting quagga mussels from the lake on the Arizona-Utah border, The Salt Lake Tribune reported Friday. The 140-mile (225-kilometer) pipeline aims to transport water to Washington and Kane counties in southern Utah. The line is planned to end at Sand Hollow Reservoir near St. George.