Federal and state officials talk openly about the difficulties and challenges of maintaining cold water through the summer to support fall-run Chinook salmon
Yesterday, officials from the Bureau of Reclamation and the state and federal fish agencies held a media call to discuss the situation at Shasta Lake and the suspension of the Sacramento River temperature plan, and how they would be updating the plan and managing through the summer.
Participating in the media call was David Murillo, Regional Director for Bureau of Reclamation; Ron Millingan, Operations Manager for the Central Valley Project; Will Stelle, NOAA fisheries; Chuck Bonham, Director of the California Department of Fish and Wildlife, and Mark Cowin, Director of the Department of Water Resources.
David Murillo was the first to speak.
DAVID MURILLO, Regional Director for the Bureau of Reclamation
Several months ago, we proposed an operational plan for the State Water Project and the Central Valley Project and proposed it to the Board. That was followed by a temperature plan that we put in place that would help us meet temperature requirements throughout the year, especially in September and October.
What happened is in May, Reclamation notified the State Board that the updated Shasta Lake temperature profile was noticeably warmer than the lake data used in the April temperature plan, and that change was beyond typical lake warming experience of past years for April and May. And so what we did is we went and examined the April temperature data and concluded that much of the shift in temperature readings was due to an instrument calibration error that caused the earlier temperature readings to read cooler than actual – about a half degree to a degree cooler. In addition to that, we also estimated what the return flows to the reservoirs would be, and those were slightly warmer than what we expected, so a combination of all of that resulted in a model that basically indicated temperature objectives of 56 degrees downstream to the Clear Creek confluence would be very difficult to reach.
Over the last several days, the five directors got together, and we were able to reach a tentative agreement on basic elements of a new temperature management plan. The elements of that plan are that there will be a base flow release that we’ll be working against, there will be temperature targets that we’ll identify, and there’s going to be a real-time ops strategy that’s going to be key on how we operate, and then ambient weather conditions will also play a key factor.
There is a lot of uncertainty as we move through the year with the conditions and how we can operate the projects and what we expect the outcomes to be. Part of what we looked at with respect to the plan as far as some of the objectives, we looked at seasonal managing of the limited cold water so that we avoid elevated temps in September and October. We’re looking at Keswick releases to help support critical supplies. There are minimum elevations in a few of the reservoirs like Oroville, Folsom, and Trinity that we’re going to try to maintain, and of course there’s D-1641 that we’re going to have to comply with. Once again, we’re in a difficult position, but collectively along with the environmental community and the ag and M&I community, we’re going to have to pull together and see how we can work together to try and make it through a difficult situation.
With that being said, I’ll turn it over to some of the other directors …
WILL STELLE, Regional Director, NOAA Fisheries
Let me offer a couple of comments. First of all, just in terms of next steps from a logistics perspective, the Bureau will be writing up the details of the program for 2015 and supporting analyses and submitting it to the Fish and Wildlife Service and NMFS. We in turn will evaluate it and analyze the effects on endangered fish species and other species, and then together submit that package to the State Water Board, probably early next week – with the exports later next week, with the expectation that the Board will then act upon it. So those are the administrative steps here.
Then let me offer a couple of observations. First of all, why does this matter? It matters because Shasta is a huge storage reservoir on the system, and the way in which Shasta operates has very substantial effects which reverberate throughout the system in the Sacramento Valley, in the Bay Delta itself, and downstream in the Central Valley, so the ramifications of how we operate Shasta are very important for people, for fish, and for farms.
From a fisheries perspective, we care because as told by the experience of last year – where last year was a bad year, a hot summer, and despite all the best efforts, we ended up running out of cold water in the Shasta pool in September. The consequences of that were that the Shasta River temperatures were elevated well above 60 degrees, and it killed most of the Chinook. This summer will likely be hotter than last summer, and we have less water, so the circumstances we’re facing here are even more difficult. And as David described, we have pulled together a program of operations that we best believe will balance the system over the course of the entire season and enable us to manage temperatures in the Sacramento system so we avoid what happened last year. That’s a major driver for this program.
The other aspect that I’d mention is simply the fact that please appreciate that we are operating this year with a set of circumstances that we haven’t seen before, and because of that, the level of uncertainty about how the river is going to operate, how the system is going to operate, and what’s going to happen is quite high. Because of that, all the fancy modeling and predictions can only go so far, and we have to put a very high premium on what we consider real time operations, which means that we will be making adjustments in these operations on a daily basis or a weekly basis as we’re watching temperatures, as we’re watching the weather, and as we’re trying to manage across the entire season. So real-time operations are going to be the key here, and we’re going to have to be on our toes across the entire season.
And with that …
CHUCK BONHAM, Director of the California Department of Fish and Wildlife
Each time we talk, I think it can’t get any more difficult and then it does for everybody involved and for everything. On the species front, there is a legitimate existential threat to survival, and on the human front, folks make planting decisions this spring based on the May temperature plan we had previously put together and now is not accurate, so that brings us having to make decisions based on the facts in front of us right now. We’re doing our best to minimize the impacts across all the important parts of California.
It’s grim, any way you slice it. Some of those facts are pretty stunning. The cold water pool Will described in Shasta, maybe it’s 30% smaller than we anticipated a couple of months ago, and we already know that air temperatures in Redding over the last three months have tracked an average of almost 7 degrees higher than normal, so less cold water, hotter ambient temperatures, and if we see a similar incredibly high mortality rate in the winter run population for a second year in a row, you really are talking about not seen before ecological crises for that run of salmon.
In the coming days, we’ll be able to put forward more information around this, but that’s kind of a state of play, and we though it important to start talking with you today about this.
MARK COWIN, Director of the Department of Water Resources
Let me quickly say that while my Department doesn’t have any direct responsibility or authority in managing Lake Shasta, all of California’s water systems are interconnected and when you tug on one string … (interruption on phone line)
We have been cooperating with Reclamation and the other agencies trying to come up with a plan that works and make State Water Project facilities available to help with Shasta temperature management. The plan you will see in the coming days will include reoperations of the State Water Project to help make that happen including additional releases from Oroville this summer to help deal with Delta salinity control while flows in Shasta are held back. As we look at all these options, of course we’re trying to balance as best we can and not impose new impacts on SWP users or Feather River water users but there’s plenty of pain to go around here.
Let me just say a couple more things. As Will Stelle noted, there is a high degree of uncertainty this year, more so than ever before. Ambient temperatures, the level of seepage and water diversions that take place in the Sacramento system, Delta conditions, how storms or wind events or high pressure events affect Delta salinity conditions will add to the uncertainty, so we’ll just have to manage through that in real-time, moving forward.
And finally, let me just say, now more than ever we need local and regional water managers to come forward with their most creative plans and their willingness to engage for the collective good to try to put together exchanges, transfers, other operational actions that we can take to try and limit the amount of impact across California.
DAN CASTLEBERRY, US Fish and Wildlife Service
Fish and Wildlife Service doesn’t have a regulatory role regarding winter run Chinook salmon, but we do have a long history of working on salmon in the Central Valley. We also have responsibility for other listed species, hatcheries, and refuges. In this case, our role was primarily to provide technical assistance in development of the plan. Like others have emphasized, the drought situation has been difficult for all of us, and it gets more challenging the longer it continues. And like others on the call, we remain committed to collaboratively maximizing flexibility and integration, especially for the listed species for which we are the federal leads, and for our hatcheries and refuges, and to do that in a manner that minimizes impacts to others.
That’s all I have to add.
QUESTIONS & ANSWERS
The call was then opened up for questions.
Question: Will this mean more cutbacks to farmers primarily or to cities … ?
Ron Milligan, CVP operations manager for Reclamation, answers: The reduced release from Keswick on the Sacramento River which is the water coming out of Shasta primarily – what we envision is that we’re going to have to work very closely with our contractors and other partner agencies who are doing operations up and down the valley, and see how best we can alleviate or shift some diversion operations, and hopefully not impact to a great extent a lot of people’s available water. That’s obviously the objective. I think we can navigate through a lot of the pain and pay even closer attention than we anticipated we’d have to in a year like this any way, but it would be a mix of actions, both within the agricultural community as well as trying to leverage some flexibility and assets within particularly our CVP M&I customers as well.
Ron Milligan continues: We’ll be working closely with the State Water Project, and as Mark said, although it’s not directly affecting any of their allocations or supplies, there are certainly a number of SWP contractors that may be able to use some of their resources as the summer unfolds and that we can make exchanges for our water facilities. It’s really too early to say just the extent of the potential effect, but the work of the agencies so far have been pretty focused on finding ways to at least take the biggest hurdles out of the way, but there’s plenty of smaller ones that we need to navigate through.
Chuck Bonham: I think you asked an incredibly important question, but I’ll remind everyone, there are impacts happening across the state in all of our core sectors. As two separate examples to illustrate that point, one of the nation’s premier recreational trout fisheries just happens to be from the Highway 44 bridge upstream maybe 5.5 miles to the city of Redding, and that turns out to be the place where the majority of winter run we’re managing spawn, so our Department restricted recreational angling and shut that down a couple of weeks ago, because we have to be managing any additional limiting factor if we expect to also turn to our agricultural friends and colleagues and ask them to take steps. Similarly, Mr. Will Stelle and my Department at the federal fishery council advocated and then formalized a reduction in the catch opportunity for the commercial salmon fishermen and fisherwomen in the ocean and the recreational ocean theory, same theory. Everybody’s got to step back and further restrict what each expects the others to contribute to the outcome here.
Question: How soon do you anticipate doing this? What is the time frame?
Ron Milligan: To some degree, what we’ve been doing over the last three or four weeks has been exactly along the lines of where we’re at right now. We’ve been working really closely with the fishery agencies and our other partners on releases that are probably very close to the range that we’re in now. The deviation from the previous plan would have been to increase releases in June and into July, and what we’re thinking now is that’s probably not a really good idea and that we probably we need to stay at a release very close at where we are today and closely manage the temperatures and the blending of water that we have to stretch this thing out.
Question: How do these releases compare to what was under the previous plan and what would it be normally?
Ron Milligan: The plan that we had submitted to the Board in April estimated that releases in June for example were going to be about 8500 cfs, possibly as high as 9000 in July, so that’s the deviation from the plan that we had submitted. Typical release in the summer would be about 11,000-12,000 cfs, maybe coming off of a really wet year, you might see even 12,000-13,000 cfs in the middle of the summer.
Chuck Bonham: The operative term there may be typical. Obviously we’re not in a typical scenario, even benchmarked against the plan we had all worked on in May. On the other side of this, there’s a relationship between flow and temperature in this section of river, and for each increment of temperature increase, you see a corresponding increase in mortality risk. Just as a general rule of thumb, if you’re over 60 degrees in the river, you’re way up to 80% mortality risk, and we’ve acknowledged that we’re not going to be able to manage for 56 degrees, and we’re now targeting 57 degrees. Those are examples of some of the things that will be right in front of us each day we proceed through the summer.
Question: The temperature has to be below 60 degrees and that is for the eggs … ?
Chuck Bonham: Each temperature has a corresponding risk factor. The lower the temperature, the better. We have traditionally managed to a temperature metric of 56 degrees; that’s not going to be possible. Once you start to get above 58 degrees, you see dramatic increase in mortality percentages, and above 60 degrees, whoa hang on, and any higher than that, you’re talking game over from a fish perspective.
Question: If the fish were wiped out this year, how many years, how many decades before the salmon were able to reestablish?
Chuck Bonham: These are incredibly resilient species on one front. They’ve been around since time immemorial, and their life journeys are awesome and inspiring, but by the same token, I think our federal colleagues have identified these winter run as one of the eight species most at-risk of extinction in the near future.
Will Stelle: These are what we call three year fish … you have a three-year cycle where every year, fish go out and they come back three years later, so think of it as a chain link. The long term viability of the population is a chain link, and each year is a link. If you kill off the kids in one year, you’ve eliminated a link. If you kill off the kids in two back to back years, you’ve eliminated two links, and it’s very difficult to try and fill in the space and reconnect the chain. If you do it for three years, your extinction rate meter goes way up, so that’s why we are very alert here in year two, after last year’s catastrophic fall, to try and make every effort to make sure we don’t repeat it, because each time you break that chain and eliminate a link, it makes it more difficult to reconnect.
Question: Do you plan to use water out of Whiskeytown Lake?
Ron Milligan: Yes, there is currently water coming from Whiskeytown through the Spring Creek Tunnel into Keswick, and it’s actually cooler water than what we’re currently taking out of Shasta Lake, so it’s helping to cool the river. That’s being backfilled to replace with water that’s being brought over from the Trinity system as well, so for the most part, we anticipate Trinity Lake being at a stable level through most of the summer. If things go really, really bad because of summer temperatures, obviously we’d be looking at all of our assets, and some last cold water in the bottom of Trinity Lake may be something we need to work with, that doesn’t mean we’re going to drain Trinity or Whiskeytown. Whiskeytown is pretty stable; but we are bringing out of Whiskeytown, but we’re backfilling it with some Trinity water as well.
Question: Will those that had transfers depending on delivery of this water – will they still have to pay for the water they won’t receive? Also asks for more information on how this happened.
David Murillo: With respect to the transfer of water, it depends on what deals were made, but there are some at risks about transfer water; whether they get the water or not, they will have to pay, and that is some of the situation. With respect to whether they are going to get the water or not, that’s still being worked out within the plan. Like we indicated, this is going to be real-time operations. We don’t want to lose temperature control at the end of the year. Part of what we’ll be proposing is can we manage in a way that we are able to at least consider releasing the transfer water, at least at the end of the year.
Rod, operations manager (no last name given): So let me describe this profile process. It’s actually a probe … this is a process that happens every several weeks. Typically in the spring it’s a monthly exercise, and then we tighten it up to every other week. What that represents is someone going out in a boat at a prescribed point in the lake, and with a probe that’s been calibrated, going out and taking a sounding of the lake and lowering the probe and measuring the temperature water at various locations as you move down from the top surface of the lake to the lower levels; this information we’ll take and run through our simulations of how the lake would warm over the summer. And that’s a process that we do, year in year out for quite a few years now, particularly since we’ve been managing the temperature control process at Shasta, and it’s a process that we do up at Trinity, Whiskeytown, Folsom Lake – it’s not an uncommon practice. But it’s not a device that’s actually fixed and permanently installed on some apparatus in the lake.
Rod continues: In the early parts of the season, we were doing this on a monthly basis and we were seeing consistent information but … going through the standard operating procedure of keeping an instrument like that in tune, sometime in late April, the instrument was recalibrated to a set of known temperatures in the lab, just to make sure that it’s reading properly. A lake probe that was done at the very end of April gave some data that was warmer than we had seen in earlier readings. Not just warmer at the top lake level which would be understandable, but even down at the lower levels of the lake. Regrettably, that was not a set of data we were using immediately in the model run, and that change was not readily detected. When we did do a second sounding two weeks later around mid May, we got some similar results, and when we tried to run that in the model, that’s where we were getting significantly different model results than our April model run. We typically run the model about once a month. We went through a series of validations with other equipment, rechecking the probe, and had consistently similar results through the month of May, but those were consistently warmer than what we had seen in the mid April time frame.
Chuck Bonham: We know the data problem; we know the model is difficult. I’m not happy about it but you have to deal with the facts we have in front of us, so I believe between us agencies, we realize we’re managing right now, but we also have to make sure we’re not in a similar spot next year. So my expectation is we’re deploying better equipment, we’re moving assets to really put elevated scientific touch on this, for example bringing in NOAA’s Climate Prediction Center forecasts about ambient temperature, because we know we’re facing some unusual spike heating events, potentially taking the model out for peer review, transparently thinking what it might look like to develop a decision support tool so we’re even better placed a year from now as we’re improving instantaneously right now in the month of June.
Ron Milligan adds: We’re also employing a lot of redundancies to make sure that the datasets were getting are informing on as best of a real-time basis as possible so that we can make adjustments quickly, because the drought and the low levels at Shasta make this even more exaggerated. And the change of the probe – it isn’t as if it was off by four or five degrees; we’re talking about less than a one degree change, but across the volume of a couple of million acre-feet, that adds up to – when you’re trying to manage to a temperature at a control point in the river, and as Chuck described, the change of a degree or two over the course of the season, it can build to some significant impacts to the fishery. So we were definitely operating at a very close margin, and that change of just less than a degree in calibrating a probe can take you to a point where you really need to rejigger your entire plan.
Question: Will this impact releases out of Folsom Lake? And is this a reduction in what you have been releasing?
Ron Milligan: The easy question is what we’re contemplating a base flow to build up or down from to manage temperatures. It is in essence the same flow rate that we’ve been at for about two weeks. Current release at Keswick is 7200, so 7250 is virtually the same number. Releases as Mark Cowin said, because Shasta is such a big reservoir in the Sac Valley system and basically the whole state water supply for a reservoir, obviously changes of 1000, 1500 cfs of what we thought we might release in the summer period previously to what we have now was a significant change, and it’s going to impact or at least be in consideration for a lot of operations. We will have to make some adjustments at Folsom from what we would have had to do in the plan from April; we’re also going to have to adjust some of our Delta operations as well, but we’ve been given some close consideration to make sure that Folsom storage doesn’t go so low that that has some really severe impacts to the availability of water for municipalities like Folsom, city of Roseville, and up at San Juan Water District.
Question: Will some entities and water agencies be getting less water because of this cutback?
Ron Milligan: Certainly the timing that they get their water is going to have to be further compromised if you will, or certainly a lot of folks were going through a lot of reoperation just to try and make ends meet. This is going to be a process that we’re going to work through over the course of the summer is how to minimize any of those effects. So it’s not necessarily a volumetric question but also a timing of deliveries, which can be fairly significant for some of the agricultural community, but also our residential communities as well. We don’t have an estimate of the loss of volume because to some degree as we work though the summer and into the fall, we’ll probably have released the same volume of water, it’s the timing that’s everything in some of these operations, and that’s the part we’re going to have to figure out how to make ends meet. There are probably are going to be some places that are going to get less water, though.
Question: Was an effort made to improve or update the model after last year?
Ron Milligan: We’ve been working with the tool to calibrate if you will or make adjustments based on what we saw last year. The big difference about last year and again this year from many years that we’ve operated for temperature control at Shasta is that the lake was not quite full enough to make full use of the temperature control device, so one of the main aspects of helping to blend water at the reservoir is not really in our tool box, which is being able to take water out at the very upper levels of the lake and protect the lower levels of colder water until later in the season. When the lake doesn’t fill, you have less cold water, but your ability to blend is somewhat compromised. So there’s a big chunk of this, which is a lack of water and cold water just because of the drought. We have made some changes to the model to be more responsive to these kinds of flow rates, and the area on the river that we’re really focusing our management to, and as Chuck said, we’re also committing to newer tools and a more robust set of tools, as well as deploying some redundancies in terms of trying to collect real time data, but even the most perfect prediction model and data collection system would probably give you answers that would say, you know you don’t have a cold water and it’s going to be difficult to get through the season, so you need some strategies to do that. And yes we would have like to known this probably a lot earlier, but they’re making a lot of tough calls a lot earlier as well.
Question: How will this affect salinity control in the Delta?
Ron Milligan: Part of the work we’ve been doing has been to think about what is, within a broad range of strategies for releases, one consideration was is there enough water here being available that allows us to maintain salinity control and in a net Delta outflow that’s protective of a very at-risk pelagic species in the Delta, and the answer is, we believe, particularly given the response of the rock salinity barrier in the Delta, it does appear that we can work with this from a salinity control and Delta outflow standpoint; the struggle will be then is there any water left over to meet some really critical water supply needs.
Chuck Bonham: One thing Ron said. Despite the difficulty of the decision making on it, arguably it would had been worse if Mark and DWR had not completed that one salinity barrier.
Mark Cowin: We’re going to be operating to the same Delta salinity standards as we would have otherwise as imposed by the State Water Resources Control Board so no, we don’t expect any changes in salinity in the Delta. It will mean that we’re going to have to release more water from Oroville in order to maintain and meet those standards, but yes we are particularly happy that the barrier is in and operating right now and we’re already reaping the benefits of maintaining salinity in the Central Delta without additional releases from upstream.
More information …
- Click here for yesterday’s press release.
- Click here for more on the drought year water actions at the State Water Board website.
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