Rio Grande Reservoir outlet works project update

From The Pueblo Chieftain (Matt Hildner):

The reservoir’s outlet experiences what Smith calls a “hydraulic jump” because of a design flaw that allows air to surge along the ceiling of the tunnel. “It’s kind of a coke bottle affect,” said Smith, who also represents the Rio Grande basin on the conservation board. That flaw has limited the amount of water that can be released from the reservoir during periods of high inflows to 1,200 cubic feet per second. Smith hopes the repairs will boost that figure to between 1,800 CFS and 2,000 CFS. State lawmakers initially approved other repairs to the reservoir as part of the $30 million Rio Grande Cooperative Project in 2012. The current proposal would add another $10 million to that initial approval, although lawmakers would decide how much of that amount is grant or a loan…

Smith sees that cooperation between privately-owned irrigation reservoirs and other interests on the river as a model for advancing water projects.

The reservoir’s main purpose is to deliver irrigation water to just 62,000 acres of farm ground in the north end of the San Luis Valley. With a capacity of 54,000 acre-feet, it is one of only three reservoirs with significant capacity upstream from where diversions begin to pull from the river for agriculture. That means it plays an important role in replacing depletions on lower reaches of the river caused by groundwater pumping on the valley floor.