Original sentence: Colorado River flows have been below average since the year 2000, leading to lower lake levels.In the winter of 2005 (before the spring run-off) the lake reached it lowest level since filling, which was aproximately 150 feet below full pool.Since 2005 the lake has risen 60 feet, but it is still 90 to 100 feet below full pool (elevation 3700 feet above sea level)
Edited sentence: The reservoir has been evaporating as much as ever, and those long-submerged side canyons are being revealed.The reservoir is currently, in the early years of the 21st century, suffering from prolonged drought