Bruce Herring: A fictional conversation
Much ado lately about the drought/climate impacts on the Colorado River. Here’s a primer on the “Compact” and “Fill Mead First,” presented as a fictional conversation in 2041. Lucy is a cable news host and Daniel a senior water engineer.
Lucy: Fill Mead First has been awhile in the making, how did these seven states get to this point?
Daniel: 120 years to be exact. Fill Mead First is a major step forward in the management of the Colorado watershed. The Colorado River Compact, approved by Congress in 1922, divided the states into the upper basin – Wyoming, Colorado, New Mexico, and Utah; and the lower basin – Arizona, Nevada, and California. Here’s the crux. Rainfall patterns in the decade prior to 1922 indicated that 15 million acre feet of water was available each year. The Compact required each basin to agree on how to share their 7.5 maf. All this led to widespread irrigation in the most arid part of the country, and major state and federal projects including Hoover and Glen Canyon dams, which created Lake Mead and Powell respectively. What we later learned the hard way was that the 19teens were abnormally wet years.
Lucy: I understand that most years there really hasn’t been 15 maf of water.
Daniel: More like 9 to 11 these days. But dam builders and water developers weren’t going to let reality get in their way in the 20th century. Members of the Compact continued to dance around these facts and discredit Fill Mead First until quite recently. A group in Utah first touted the idea around the turn of the 21st century. As time went on the group became more sophisticated. Their data clearly suggested that Fill Mead First would keep more water in the system. Built in the 60s, Lake Powell first filled in 1980, nearly overtopped in ’83, and remained mostly full throughout the 90s. Climate change and aridification in the early 21st led to an inexorable downward trend in lake levels. Many hydrologists felt it unlikely that Powell/Mead could ever both be full again. Under pressure from the Feds in 2007, the seven states developed Interim Guidelines and drought contingencies. The guidelines were given a 20 year lifespan and negotiations for the 2nd Interim Guidelines began in 2020. By then it could no longer be denied that the supply and demand imbalance was a long term systemic reality. In ’18 and ’22 the basin states and Mexico had to further reduce allocations.
Daniel: Yep. In 1944 an additional 1.5 maf was allocated to Mexico. Fill Mead First began to get serious notice during the negotiations and was formally adopted with the 2nd guidelines in ‘26.
Lucy: And then.
Daniel: It’s been a three stage process. Phase One was accomplished naturally as Powell dropped below “minimum pool” – at which point the production of hydro-electricity was dramatically reduced. With higher releases downstream, lake levels continued to drop in Phase Two, down to where power generation stopped altogether. At that point (2030), Phase 3 began. To help fill Mead, the flow below Powell was kept to a minimum of 15,000 cfs, while massive bypass tunnels were constructed on either side of the dam. They actually re-furbished the original 1950s tunnels – each 30 feet with a capacity of 100,00 cfs. If that capacity is reached, which would be a significant flood event, water would begin filling up the reservoir behind the still standing dam. Small in-stream hydro-electric units within the bypass tunnels provide several hundred megawatts of electricity for Page, Arizona. All that took about four years. Today the flow of the Colorado resembles the pre-dam seasonal fluctuations through Grand Canyon, and the entirety of Glen Canyon has re-emerged. Though some silt remains, the canyon itself and the numerous slot canyon side creeks have rebounded to an astonishing degree. The upper basin states – yet to reach their full allotment – are “banking” water in Mead thru the approved ICS agreement, and can sell water to the lower states in dry years.
Lucy: So is it working?
Daniel: For the time being yes. Though there were a few critical years in the 30’s when drought contingency plans were imposed, the 2nd Interim Guidelines and Fill Mead First have saved the Compact from further chaos and federal intervention.
Lucy: So more needs to be done?
Daniel: Absolutely, and remember the 2nd Guidelines expire in 2046 and we are about to enter negotiations. But that’s another story.
Bruce Herring lives in the Peardale area and is a member of the Union Editorial Board
The service workforce is fading into extinction. I’m talking about the people who make the very existence of commerce thrive. The people who show up to work as scheduled and on time with the work…
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