Water release 2018 2019

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Hey has anyone else noticed the amount of water released for the 2018-2019 year was way more then the required amount ?
Will they make up the over release in the 2019 -2020 season ? We were on lake early spring and I had never seen lake that low . Just wondering why there was not more discussion on the overage of water that was released.
Not really sure about the overage of water released but I do know that we went almost a full winter that year without any measurable precipitation which was a HUGE factor in why the water was so low in early 2019.

I'm sure someone who follows the water tables by the years will chime in and hopefully someone will know why more than needed was released. If my memory serves me right, I think there was an emergency proclamation for the dangerously low level at Lake Mead and forced more release. I'm sure someone will chime in if I'm wrong. lol
The 2018-19 releases were in accordance with the Bureau's operating requirements relative to managing and balancing Powell and Mead. A "normal" release from Powell would be 8.23 MAF, but yes, last season it was 9.0 MAF, which was required based on the water levels in the two reservoirs. Notably, the total storage in the Colorado River system (all reservoirs) increased by 3.64 MAF, which practically speaking means the system went from 47% full to 53% full.

Unregulated inflow into Powell last season was good but not great historically speaking, because while the year ended with a bang, it didn't start that way. It ended up being 12.95 MAF coming into the lake--about 120% of average--but still far below the biggest years of the mid-1980s, plus a few others such as 1993, 1995, 1997, and 2011. But if you discount 2011, it was the best year since 1998, and that's saying something.

This coming year's projections look very interesting. The Bureau actually projects inflow to be slightly below average (88% of average, which is 10.83), at 9.5 MAF. There's a huge variance in that projection, however, which all depends on snowpack--it could vary anywhere from 6.7-18.0 MAF. Very hard to tell. Here's a graph:

What does this mean for forecasted lake levels? Again, a huge variance, in part because releases could vary depending on how much inflow there ends up being, and what the releases will be. Right now, the operating protocol projects the normal release of 8.23 MAF for the year. Based on this, the current "most likely" prediction is that we end up at 3624 on 9-30-20, after a peak of about 3627 in late June/early July. The projected "worst case", however, would have the lake peak at 3605 in June after an early 2020 minimum of 3595, and then slowly slide to about 3595 again by 9-30-20.

But the "best case" scenario is very exciting--if they kept releases at 8.23 MAF, and have a huge snowpack year, we'd end up near 3680. Practically speaking, if we had such a year, they'd increase the release volume to 11.89 MAF to benefit Mead when things got cranking, but even so, we'd still end up at 3657 on 9-30-20 after a summer peak somewhere north of 3660.

Here's a link to the lake level projection graphic:

And here's a link to USBR's full report from October 11 that goes into more detail on all this...

Well all good info but when I look on Wayne’s words and the water stats page it shows 7,500,000 maf is the required annual release of water which this year occurred on the 11th month of water release so if this is the correct water release agreement and all the lower users can live on the shared release why are they letting out additional water ? Why not bank and save every drop they can for the drought years that may be ahead .
The Water Database page is not "official" in any way relative to the Bureau of Reclamation. It is merely a collection point for various data available from the BOR and other sources. That Minimum release number has never been updated to my knowledge. Always refer to the Glen Canyon operations site(see JFR's link above) for the current release plan for the lake.
A short summary of the key issues related to water releases...some of this is recycled from an earlier post I made to a different thread, but thought it might be useful here too...

...As you might suspect, it's more complicated than the LP Database indicates. If you want to read the entire set of moving parts that goes into the "Law of the River", here's the link. If you have time, go for it--pretty interesting:

The short version is that the Upper Basin needs to deliver 75 million acre feet in any given 10-year period to meet the delivery requirements to the Lower Basin, or a yearly average of 7.5 MAF. In addition, the Upper Basin has to deliver its share (half) the 1.5 MAF to be delivered to Mexico, since the river ends up in Mexico. Under the current protocol followed by the Bureau of Reclamation, that means the usual "minimum" release requirement is 8.23 MAF, not 7.5 MAF, to account for release requirements to the Lower Basin and Mexico. There is some flexibility in that. The Bureau can release up to 9.0 MAF in order to achieve a better operational balance between Mead and Powell. There's a few other nuances there, but that's the idea.

So all this means that means the LP Database is a bit oversimplified/misleading. For example, instead of saying we are at "10% of the minimum required 7.5 MAF", it should really say we are at "9% of the projected release of 8.23 MAF", if the intent of the USBR is to release that much during a given water year.

Of course, the critical component in this arrangement right now is Mead, not Powell. If you get below 1075 in Mead, then some real changes in the Lower Basin happen, mostly that not everybody gets their water allocation--specifically, AZ and NV do not get their full share (CA has the senior water right among the three states, a separate topic--CA doesn't have to cut back until it falls to 1025). So there's a very strong effort to keep it above 1075, with especially loud voices in AZ and NV since they'd be affected first. Today we're at 1082, only 7 feet above that critical level.

Powell, on the other hand, is not really tied to any level in terms of Upper Basin water delivery, because nobody in the Upper Basin really draws directly from Powell except the City of Page (the Navajo Power Plant did too, but now it’s being shut down). And if it ever happens, the proposed pipeline to St. George would draw off a relatively small amount annually--about 0.86 MAF (although hydrologically St. George is really in the Lower Basin, legally it's considered in the Upper Basin because it's in Utah). For Powell, right now it's mostly about acting as a storage bank for Mead and for power generation through Glen Canyon Dam, and the minimum power pool for Powell is 3490. We're at 3613 right now--not close. So from a management standpoint, Mead is under way more stress than Powell, so it makes sense to send as much as possible in the allowed range (8.23-9.0) down to Mead as long as water delivery requirements downstream are in jeopardy. And in a big water year, it makes sense to send as much as possible downstream. That's what happened during Water Year 2018-19, but even with that, Mead has been slowly dropping from the most recent peak of 1090 on March 31... and that's with the Lower Basin states staying within their allowed usage per their water rights.

So that's the reality from a legal framework...

Of course, the whole thing is based on the assumption that the river system can deliver 16.5 MAF to all users on an average annual basis. The reality is that average flows over the past century are much less than that, more on the order of 11 MAF +/- since 1981. Last year—which was a very good year—only saw about 13 MAF inflow into Powell. So while some years may exceed 16.5, the vast majority do not (since 1964, only 5 years have experienced inflow into Lake Powell that exceeds that figure), which means in the long run, water rights exceed supply, and the reservoir levels will inevitably trend downward if everyone exercises their water rights, even with the occasional up years. And the long-term forecast in terms of climate change is that the SW will experience less precipitation in general over the next century, not more. And more people continue to move to the West, so water demand continues to rise. Of course, the elephant in the room is "what if the Upper Basin exercises its currently unused water rights?" Then there's a big fight, of course. What we're seeing now with regard to the St. George pipeline is just the beginning of that conversation...

That's why cutting back demand is the critical approach if a sustainable balance is ever going to be achieved, which is hard to do within an established water rights framework... but that's the whole point of the recent agreement among the seven basin states...
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Very impressive info for sure. Here is my point the time for water conservation is now fill the reservoirs with every thing we can now , we all should be under critical water Right now until there is a 3 year bank of water stored . Can you imagine what would have happened if the 2017-2018 drought would have continued for 3 more years the resivores in our area were near empty by the end of the water year 2018 .Blue Mesa, Taylor resivor morrow point, Crystal resivor all were almost empty that all feed Colorado river. Lake Powel would have been empty and lake mead also. Then what coach. It would be ugly. My suggestion would be to keep a 3 year reserve in Powel and lake mead Combined and allocate 75 percent water until the 3 year bank of water has been achieved . Well thanks for the information I hope we don’t see the bank in lake Powel that low again I pray people will use there nogin to protect their selfs from future drought years.
oh I did find the water compact agreement from 1922 interesting.
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