From the Sky-Hi Daily News (Tonya Bina):
In the shallow, “crystal clear” connecting channel of Grand Lake and Shadow Mountain Reservoir, “The day after they started pumping, you couldn’t see the bottom,” said Watershed Program Manager Ben Carver, of the Grand County Water Information Network. Secchi disc measurements back up observances…The Water Information Network’s paid field technician has been sampling clarity at 14 sites of Grand Lake three times per week this summer. In mid-July, the measurements averaged around 20 feet (6.25 meters). On Sept. 10, three days after pumping resumed, the clarity on Grand Lake had been cut nearly in half to an average 11 feet (3.25 meters). The channel became “a bottleneck for all the algae coming into Grand Lake” from shallow Shadow Mountain Reservoir, Carver said.
More Colorado-Big Thompson Project coverage here.