At the National Water Research Institute’s Drought Response Workshop held last month, DWR Interstate Resources Manager Jeanine Jones gave a presentation on current statewide water conditions and preparations for a potentially dry 2014. During her presentation, Ms. Jones discussed how drought impacts are measured and managed, presented information on groundwater declines from the CASGEM system, and highlighted the impacts of wildfires, especially for small water systems.
“A lot of things have happened the last couple of years,” Jeanine Jones began, presenting a map depicting the percent of average precipitation for the Western U.S. for the last two years. “A lot of the west has been dry, California, certainly, as well as the Colorado River Basin, which is also important for Southern California. If you look at the map of California overall, you see that there’s definitely a gradient of precipitation there, although the north has been dry, the south has been drier.”
The last wet year was 2011, she said. “2012 was the first dry year, but because 2011 had been wet, we had pretty good reservoir storage going in, so it wasn’t a big issue.” She noted that even though this year was a dry year, it started off with record wet conditions which helped replenish reservoir storage.
This year, the State Water Project and the federal Central Valley Project had less than ideal supplies for many of their customers, especially with respect to the federal projects supplies that are delivered south of Delta, and that’s a reflection of environmental regulatory constraints and reallocation of water for environmental purposes as well as just the hydrology, said Ms. Jones.
“Out of the past 14 years in the Colorado River Basin, 11 of them have been dry, so we have had a sustained long-term dry period on the Colorado River,” she said. “However, because of the significant amount of storage in that river basin, there are no impacts to California and frankly a low probability of future shortages to California within the next few years.”
Defining drought
So when does it stop being merely dry and becomes a drought? “Drought is really in the eye of the beholder – it’s a function of impacts,” she said. “The analogy that I always like to use to describe it is that it is like the difference between a recession and a depression. A recession is when your neighbor loses his job; a depression is when you lose your job. The perception of dry and drought works the same. It’s dry if you’re just hearing weather reports and somebody else is having problems, but if you have full supplies, it really doesn’t affect you too much. On the other hand when your supplies are tight, then suddenly, all of a sudden, it is a drought.”
There are many different ways to define drought. “A meteorologist, for example, might say that drought is a period of extended low precipitation – precipitation below average conditions,” said Ms. Jones. “A hydrologist could say similar idea, but runoff instead of precipitation. We’ve all heard the term regulatory drought; it’s tossed about a lot with respect to conditions in the Bay-Delta and how things like fishery protection has caused a reduction in water deliveries to water users, so you hear the term regulatory drought used, and that’s somewhat independent of hydrology.”
Measuring drought impacts
There are also many different indices out there to measure drought. “Many local water agencies have triggers they might use in their water conservation plans that tend to usually be based on supply from their wholesaler or the status of their groundwater basin, those kinds of things,” she said.
“There’s also the U.S. Drought Monitor,” said Ms. Jones. “It is a tool that was developed by the University of Nebraska Lincoln, and because it was developed in Nebraska, it really focuses on conditions that affect non-irrigated agriculture, such as precipitation and soil moisture. It’s an attempt to characterize at a very widespread scale, ie the entire United States, what conditions look like. If you’re an urban water supplier in California, it’s almost meaningless because it really doesn’t reflect water supply conditions. It’s really more reflective of precipitation; it wasn’t designed to deal with the way we move water around in California where supplies come from many hundreds of miles distant, and it also doesn’t incorporate groundwater, so when you see the drought monitor, it may actually look worse than it is, from a water supply perspective.”
The USDA drought disaster designations are a tool that is used for making financial assistance available to growers and the trigger for it is very low, she said. “It’s somewhat unfortunate they use the term ‘disaster’ because it’s not the typical meaning of disaster that the person in the street would expect.”
The USDA designations are an example of a sector-based definition of drought, she said. “If you’re a farmer and something went wrong, it’s a disaster to your income, perhaps, but this illustrates that different sectors of the economy have different perception of droughts, and this is why we say that drought is a function of impact because if you have a lot of resources to mitigate the effects of water scarcity, it may not be that much, it’s not the same level of impact to you as to someone who lacks those resources.”
Managing drought
“In California, we’re fortunate to have many different ways or tools to use in managing drought, much more so than many other states,” she said, noting that in some parts of the West, they do not have infrastructure that allows them to move water around or a lot of groundwater resources. “In California, we’re very fortunate not only to have the physical infrastructure but we also have an institutional infrastructure that does things such as facilitate water transfers for example, which you cannot do nearly as easily in many other western states.”
“Drought happens; we know that,” said Ms. Jones. “It’s a normal part of the hydrologic cycle, and we have lots of warning. This is not an emergency like a flood or a forest fire or an earthquake where suddenly it happens and you have to respond. Droughts develop over multiple years. And we have lots of time to implement response activities like water conservation, water transfers, and water exchanges.”
“Drought is not one size fits all; it affects different people differently,” she said. “People relying on what we call unmanaged water, such as non-irrigated agriculture and grazing – they are affected right away because they have no tools to deal with it, and the USDA disaster designations are really driven by grazing.”
“How much you’re affected in a drought depends on your ability to afford reliability,” she said. “Urban water users can do things like water recycling projects or desalination projects that are very useful as a drought mitigation and response measure, but for small water systems on unreliable groundwater sources, this is really the big problem.” Those systems exist in the foothills of the Sierra Nevada, some areas along the North and Central Coast, eastern San Diego County, and the foothills of the Inland Empire, she said.
“Large water agencies can really handle three to four dry years with minimal impacts and in fact, today at the end of a second dry year, there’s literally only a handful of municipal systems in California that have even called for voluntary conservation, clearly reflecting the good storage and groundwater conditions and that people are well prepared for this,” she said.
Groundwater
Ms. Jones then presented a series of slides of groundwater maps. The first was a map of the state of California showing changes in groundwater levels from between the spring of 2012 and the spring of 2011 – a dry year to a wet year; the red dots and warmer colors represent declines.
She then presented a map of the next year, spring of 2013 to spring of 2012, with much more red, depicting dropping groundwater levels in the Central Valley. “The red is where we have the largest percentage of overdraft in California,” she said.
She then presented the same slide but with a different scale that more clearly depicted the areas where groundwater level declines had been the steepest. She explained that the previous slides used a scale where red was only a 10 foot decline, but with this map, red is more than 50 feet decline. “What’s going on in the southern end of the San Joaquin Valley really stands out here, and it’s not a huge surprise because we know this is an area where there’s been long term overdraft conditions of groundwater,” she said.
The California Statewide Groundwater Elevation Monitoring System was established by the 2009 legislation and requires local agencies that overlie groundwater basins to report water levels data to the state. “For those of you who are submitting data, we very much appreciate it, and thank you, because this is what allows us to take a look at groundwater at a statewide level.”
Predicting the coming water year
“One of the big challenges in drought management is the fact that we can’t predict when we’re going to have dry conditions,” said Ms. Jones. “Every year, the Department has been holding winter outlook workshop which is an experimental research forecast in which we bring together some of the scientists at Scripps, get together and talk about what we expect to see. We then publish a summary of that on our website. Unfortunately, the capacity for drought prediction or interseasonal to interannual climate forecasting, to be more precise, is not really good.”
“The strongest predictive ability that they have is the status of ENSO, El Nino Southern Oscillation conditions, out in the Pacific Ocean,” she said. “This year, it looks like ENSO might be neutral which really takes away most of the value of that predictive capability, so it’s really going to be pretty much a coin toss as to what this year could be.”
We need to plan for the possibility of another dry year, she said. “As we go into this year, we have generally dry antecedent conditions, so even if we get average runoff, a lot of that will be lost to replenishing soil moisture and those kinds of things. … We know that storage in groundwater basins has been depleted, especially in some of the fractured rock basins that are critical for small water systems, and we know that in areas where there have been wildfires, there is a high potential for mud and debris flows and after effects of that.”
Going in to the next year, we’re at about 78% of statewide reservoir storage, she said. The Colorado River Basin remains dry, but that won’t be a problem for us. Soil moisture is depleted, and that’s an issue in terms of wildfire risks and effects to the grazing community, she said.
Risks if 2014 is dry
If 2014 is dry, wildfire will be the biggest risk in terms of its economic, public health and safety impacts, she said. Small water systems, those with less than 500 connections, are especially at risk. “Many of those systems struggle to maintain water supplies even in wet years, let alone average or dry years. They tend to be located in areas outside of a large municipal provider and they often have fractured rock groundwater sources which tend to be quite unreliable.”
“We spend a lot of effort thinking about how we can help these small systems which is really a daunting task when you consider that they have no financial capability, many of them have only one or two people on staff and they are too small to have conservation programs, so it’s quite a challenge,” she added.
“Wildfire is a huge threat to small water systems,” she said. “The last state water bond had provided an emergency fund to CDPH for emergency assistance for smaller water systems. Half of the money in that account went to small systems that lost infrastructure in wildfires, such as electrical systems, lost pumps, and storage tanks.”
“In terms of the bigger water systems, CVP deliveries south of the Delta like the Westlands Water District area, for example, have had almost a new normal with respect to water supply conditions ever since 1991 when the CVPIA was enacted; that combined with the environmental requirements for fishery protection mean that even in a normal year, they would not get a 100% supply,” she said. “In fact, with respect CVP south of Delta, they’ve only had a 100% supply in three years since 1990. You may have seen the articles in the press where the Bureau has said that their initial allocations, even if its average hydrology this season, would be probably 0% for the CVP south of Delta, so there will be a big impact for that farming community.”
How is DWR preparing for another dry year?
The Department of Water Resources is doing several things to prepare of another dry year. They are conducting outreach workshops to emphasize the need for planning; the Department has received federal funding to partner with California Rural Water Association to conduct drought preparedness workshops for small water systems.
“We are very grateful to have the data you all are submitting to the CASGEM program for groundwater because it allows us to monitor for impacts, and we’re in the process of doing a contract with JPL to use satellite-based radar technology to update subsidence monitoring in the San Joaquin Valley,” she said. “We know that areas like the San Joaquin Valley have a high subsidence risk already, and in fact, there are some places in the Valley where in the last two years, we’ve lost 2 feet of elevation.”
The Department is also funding research-level climate forecasts, tracking impacts, and considering the possibility of convening a state agency coordination committee in early 2014.
“Statistically speaking, if you just looked at probability, you could say we maybe have a 33% chance of a dry year: three options – wet, dry, or average, purely on probability,” said Ms. Jones. “However, we know Mother Nature doesn’t work that way. Unfortunately, we haven’t been able to predict how Mother Nature is going to work, so we’re at the point where we say that we hope for the best but we need to prepare for the worst.”
For more information:
- Click here for Jeanine Jones’s power point.
- Click here for the video of this presentation.
- Click here for all presentations and videos for the workshop.
