I’m still new to the strange and wonderful ways of lower Colorado River management, so I was struck by the hilarity of this situation, as explained by Chris Brooks. Farmers order water, which takes several days’ river time to reach them. But then it rains, so they don’t need the water, so it flows down the river – horrors! – unused:
I’m sure there are a lot of water agencies that shudder to think that, at times, water is being released from Lake Mead that isn’t used by anyone.
I am reminded of Andy Revkin’s post of several weeks ago, which mentions clams as possible downstream users who might benefit from such a situation.
That’s why Vegas and MWDSC are funding a dam on the “end” of the river — to catch those “lost” flows before they cross the border to MX — and THEY get ’em….
There was an editorial just last week in the (soon-to-be-defunct?) San Francisco Chronicle by state senator Dave Cogdill (republican from the Central Valley) where he notes: “Water is literally going down the drain. In 2005, enough water to supply 13 million families for a year went out to sea and was lost because there was nowhere to store it.”
http://tinyurl.com/d3xsng
This prompted several letters to the editor a few days later where it was pointed out to the senator that it is, in fact, the function of rivers to deliver rain water to the ocean.
Chris Brook’s comments:
I’m sure there are a lot of water agencies that shudder to think that, at times, water is being released from Lake Mead that isn’t used by anyone.
Water districts (irrigation districts come to mind) always have a little extra water in the system to make sure that the far-end customer will receive water. Any excess is returned back to the river through a drain the district has. A return credit for the water is given.
In the case of excess water in the system (due to canceled water orders or unexpected inflows into the system), is the scenario being described by Chris. Any ‘excess’ is not being passed to the Delta – but being siphoned off at Morelos Dam (and sent down the Alamo canal). A limited amount of control is done by the pumped storage facility at Senator’s Wash (at Imperial Dam).
Too little control it seems for the changes that happen. The Drop2 reservoir is designed to ‘catch’ any excess water that the system has. Not a perfect solution for a problem of water releases and end use – but one that helps to minimize the losses the system has.
Think about how well the system is actually controlled. Water is released at Hoover. The same amount (give or take) is re-released from Davis Dam hours later. After Davis Dam – water begins to be used starting in the Mohave Valley by irrigators. Lake Havasu is the next link in the chain. Here, distribution takes a new nature. Here, the river takes several routes: Pumped at Mark Wilmer (CAP), Whitsett (MWD) pumping plants and through Parker Dam. Fifteen miles below Parker Dam – CRIT takes water at Headgate Rock Dam. Another forty five miles down river PVID gets their share. Next stop, above Yuma, is IID (All American Canal) and the Gila Canal (Welton Mohawk).
Considering the number of ‘end users’ and the variables in the equation – I’m surprised that the losses are as small as they are.
Any problem ‘upriver’ from IID will show up as excess flows. To anyone who looks at this at face value – sees some measure of mismanagement or waste. To someone who has some knowledge of the nature of how the system operates – sees that control of this resource is not an exacting science.
Anyway, that’s the way I see it.
dg
Excellent points, Delbert. I agree for the most part that the operation of the river is probably as tight as it possibly can be. I was mostly enjoying pointing out the irony of the timing of the two news stories. But as I think I pointed out in response to your comment on my blog, small losses by the ag sector (often unavoidable and seemingly insignificant) can appear to be significant augmentation opportunities for the municipal sector. I think there needs to be much more pursuit of slack in the system by urban interests to re-allocate “waste” from the ag sector. Unfortunately as David Zetland and others have pointed out, this is often hindered by the governance structures of irrigation districts. So many seemingly simple fixes that are ever so difficult to implement.
Chris,
Your Blog entry on the ‘irony’ of the situation was spot on.
Funny how some things operate. Once the water is in the system (released from Hoover) the only control can be in the releases from Davis Dam and Parker Dams. After Parker Dam, there is very little regulation (in the form of reservoir storage) for the water. Reservoirs can absorb any excesses that the system may have – the level simply rises if more water is encountered.
Below Parker Dam, the reservoirs are used to raise the river’s elevation for water diversions (Headgate Rock – CRIT, Palo Verde Dam – PVID, Imperial Dam – IID). Elevations are maintained in these bodies of water to push the water through the local diversion canal.
The Yuma Sun Article you cited in your Blog talked about a small rainfall in the Yuma area causing farmers to cancel their water orders. When it rains out here in the West – for the most part it is a ‘local event’. That is – it can rain 0.3 inches at Yuma’s airport (where the NOAA takes the measurement). Five miles away in some farmer’s field the amount can be a lot more (or less). The point here is is that the article can be somewhat misleading in the point that it is making. I’m sure that you have noticed the locality of rainstorms in the Tucson area.
I wanted to also comment on the AG sector. Irrigation districts view efficiency as how well they can maximize the water that they take. This actually equates down to how many acres in their district they can support. To be efficient is a combination of being able to distribute the water within their system with minimum losses while being able to deliver to the ‘last customer’ on the lateral.
Inefficiencies happen at two levels here. The first is at the district level (over deliveries and spills). The other is at the Farmer level (using more than what is actually required).
Without using some sort of ‘control’ (flume, duckbill weir, etc), measuring water in the field is not an exacting science. I would guess that most disbursements favor the farmer. What do we do here? Automation in the field is a good start. The problem here is that adding automation in the form of a PLC or DCP (Programmed Logic Controller, Data Logger) requires a skill set that most irrigation district employees do not possess. This is most certainly true of the farmer. Bottom line – Automation and smart sensor technology is not a ‘turn key’ thing. You don’t deploy a system like this without having to maintain & and calibrate it. By the way, most districts pay employees a minimum wage. Hard to attract and retain a quality employee that understands Instrumentation and Control for under $20/hr.
This is one of the things that I’ve seen. I consider this as a major obstacle. Investing in automation at a district also means investing in the support personnel. It is hard for the district to make cash outlays to improve operations. Farmers complain when money is spent. At best – it is a shaky situation.
As you said – simple fixes are not easy to implement. If it was simple and cheap to accomplish, they’d do it.
Anyway, that’s the way I see it.
dg