Taking the temperature of streamflow forecasts: #Climate information improves forecast accuracy in the U.S. Southwest

From AtmosNews (UCAR/NCAR):

Adding temperature predictions into seasonal streamflow forecasts in the U.S. Southwest could increase the accuracy of those forecasts, according to a new study that analyzed historical conditions in the headwaters of the Colorado and Rio Grande rivers.

Many rivers in the western United States are fed by melting snow in the spring and summer. Regional water managers depend on seasonal water supply forecasts that estimate the amount of runoff the snowpack will yield to determine how much water to allocate to farmers and ranchers, city residents, and other users.

These forecasts, which are based on snowpack measurements taken in the winter and spring, tend to assume that the climate is stable and that the relationship between the amount of snowpack and the amount of runoff is also stable.

But a recent study by scientists at the National Center for Atmospheric Research (NCAR), the National Oceanic and Atmospheric Administration (NOAA), and the Bureau of Reclamation found that warmer temperatures reduce the amount of meltwater that actually makes it into a stream, a finding that highlights the importance of accounting for changing climate conditions when forecasting streamflow.

Building on this work, scientists at NCAR tested whether incorporating seasonal temperature predictions into statistical streamflow forecasting models could improve their accuracy. The temperature predictions reflect the recent warming trend as well as whether the months after the forecast date are likely to be warmer or colder than this trend. Results of the new study were published in the journal Geophysical Research Letters.

“Adding temperature predictions into streamflow forecasts will not only improve the information that water managers have today, but it also has the potential to mitigate some of the loss of predictability that we now expect in the future, as the climate continues to warm,” said NCAR scientist Flavio Lehner, who co-led the study with NCAR scientist Andy Wood.

The research contributes to an NCAR effort, in collaboration with several federal agencies, to build better tools and models for analysis and prediction of water resources. The new study was funded by the NOAA, the Bureau of Reclamation, and the U.S. Army Corps of Engineers.

Other study co-authors include Angus Goodbody from the National Water and Climate Center, which issues streamflow forecasts for the western United States; Florian Pappenberger from the forecast department of the European Centre for Medium-Range Weather Forecasts; and Douglas Blatchford and Dagmar Llewellyn, both from the Bureau of Reclamation.

COMPARING “HINDCASTS” WITH AND WITHOUT TEMPERATURE PREDICTIONS
To test whether the addition of seasonal temperature predictions could improve streamflow forecasts, the scientists created “hindcasts” for the headwaters of the Colorado and Rio Grande Rivers (both located in Colorado) for the three decades between 1987 and 2016.

The team used historical observations of snowpack, precipitation, and streamflow to issue and evaluate a series of forecasts — on Jan. 1, Feb. 1, March 1, April 1, and May 1 — for each year. These hindcasts emulate the current method of issuing streamflow forecasts, including the calendar dates when those forecasts are issued.

The scientists also issued a second set of hindcasts, this time with the addition of seasonal temperature predictions for the region. The seasonal predictions were drawn from the North American Multi-Model Ensemble and the European Centre for Medium-Range Weather Forecasts, which together comprise eight state-of-the-art models used for seasonal climate forecasts.

The team found that incorporating temperature predictions improved the accuracy of seasonal streamflow forecasts at the majority of river gauges across the headwaters of both basins. The amount of improvement varied between about 1 percent and 10 percent, averaged across the basins.

“We think that model-based temperature predictions could be used to improve water supply forecasts in other watersheds that rely on runoff from snowpack — across the western United States and in other parts of the world,” Lehner said “But the degree of improvement will certainly depend on the individual area.”

SMOOTHING THE PATH TO ADOPTION
To make it as easy as possible for existing operational forecasting centers to begin incorporating the research findings, the scientists chose to modify existing forecasting techniques to include temperature predictions instead of inventing an entirely new forecasting method.

“It’s a well-known challenge to transition methods from a research experiment to an operational setting,” Wood said. “Here we chose a baseline of a current operational water supply forecast technique so that the approach is an extension to the existing practice, and more likely to be supportable.”

Fostering these kinds of applications is the overarching goal of the Postdocs Applying Climate Expertise program that supports Lehner’s research. PACE is run by the Cooperative Programs for the Advancement of Earth System Science, a community program of the University Corporation for Atmospheric Research.

“This project has enabled stakeholders and scientists to work together directly to tackle a concrete water-related problem arising from the variability and trends we’ve observed in our regional climate,” said Llewellyn, a scientist at the Bureau of Reclamation and study co-author.

ABOUT THE ARTICLE
Title: “Mitigating the impacts of climate non-stationarity on seasonal streamflow predictability in the U.S. Southwest”

Authors: Flavio Lehner, Andrew W. Wood, Dagmar Llewellyn, Douglas B. Blatchford, Angus G. Goodbody, Florian Pappenberger

Journal: Geophysical Research Letters, DOI: 10.1002/2017GL076043

Interview: Andy Mueller General Manager of the #ColoradoRiver District #COriver

Andy Mueller photo credit MountainLawFirm.com.

From The Grand Junction Daily Sentinel (Dennis Webb):

Coming from water-abundant Ohio, Andy Mueller used to have trouble explaining his line of work to relatives on trips back east.

“When I used to say ‘I’m in water law,’ they’re like, what, are you a sewer lawyer?

“I think that’s one of the unique characteristics about the West, is the scarcity of water is what drives our communities and the value of a reliable water supply is so critical to vibrancy of a community on the Western Slope,” Mueller said.

These days, Mueller is in water policy, as the new general manager for the Colorado River District, a taxpayer-funded, 15-county entity based in Glenwood Springs. Such work is a little easier to explain back east, and even among western Coloradans, describing what the river district does can be difficult. But Mueller says that at its core, the district advocates for water users on the Western Slope.

While historically, water has been depicted as something that has driven a wedge between communities, “I think it should be something that ties our communities together,” Mueller said. “We all need it, we all depend on it, we all want it in one way or the other. If we can work together (on water) we’re much stronger.”

Mueller was an undergraduate student pursuing his history degree at Kenyon College in Ohio when he took a class on history in the American West and became intrigued about the region.

“I remember thinking, I wanted to get involved in that,” he said.

Mueller, 49, moved out west to get his law degree at the University of Colorado, having been attracted to the school because of its reputation for natural resources law. Almost immediately after becoming an attorney he was able to take over a practice in Ouray in which he focused heavily in areas such as water and hard-rock mining, working with clients across western Colorado including farmers and ranchers, Ouray County, developers, logging companies and others.

“I really learned from my clients what it meant to live on the Western Slope and it was a really good experience,” he said.

In 2006 he was appointed as Ouray County’s director on the Colorado River District board, eventually serving nine years on the board, including two as president. One of the key accomplishments during his board years was the cooperative Colorado River agreement reached between the district and other Western Slope entities and Denver Water. After decades of expensive legal battles, the agreement provided a path for Denver Water to develop water while addressing Western Slope concerns such as the need for river restoration.

“We were able to really get some significant commitments from Denver to participate in very important projects for our headwaters communities in terms of the health of our river systems,” Mueller said.

He eventually relocated his law practice to Glenwood Springs, joining a firm there. Meanwhile, longtime river district general manager Eric Kuhn made the decision to retire.

Mueller said he was pretty upfront when he applied to replace Kuhn that he couldn’t fill Kuhn’s shoes.

“He’s really a giant in the intellectual world of water policy but I have other skills and talents I think will serve the district well,” Mueller said.

Mueller said the district has two charges — to protect the Western Slope and Colorado’s share of the river.

“That’s a very significant charge for a little government agency like ours,” he said, noting that there are other well-funded water entities out there looking after the interests of millions of people the river serves in places including Phoenix, Las Vegas and Southern California.

For Mueller, a major issue facing the district is the increasing variability of climate and the changes that result. Growing seasons are lengthening, which can benefit agriculture, but also mean more water consumption. At the same time, recent droughts have meant decreased flows into Lake Powell, which Upper Basin states rely on for meeting obligations to downstream states that already use more water than they’re entitled to under an interstate compact.

“The biggest issue we have as a river district is helping the basin as a whole try to bring the system into balance,” he said.

Mueller said it’s important to do drought-contingency planning and look to conservation while keeping in mind how to accommodate projected growth and development.

The district has been involved in initiatives such as analyzing pilot projects for limited rotational fallowing of agricultural land for farmers who are compensated in return. The goal is to explore alternatives to buying and permanent drying of agricultural lands to meet municipal water needs should drought lead to a water supply crisis. But Mueller said it’s important that agriculture be protected and that Eastern Slope cities and farmers also do their part to head off shortages.

“If our agricultural community is going to step up and contribute, so should everyone who depends on Colorado River water,” he said.

Mueller and his wife, Kara, are raising two high-school-age girls in Glenwood Springs. Mueller enjoys water recreationally as a rafter and fly-fisherman, and also hunts elk, mountain bikes and skis. He said it was hard giving up his law career, but it was worth doing so to get to work with a talented staff at the river district. He sees his new job as a logical progression after 23 years of advocating for Western Slope families as an attorney.

“Now I get to (advocate) for the entire Western Slope and that’s why I’m excited about this job,” he said.

Pitkin County embraces reuse of household graywater — @AspenJournalism

From Aspen Journalism (Brent Gardner-Smith) via the The Aspen Times:

Pitkin County is now the second county in Colorado that can issue permits for graywater systems that allow some household water to be reused to irrigate lawns and flush toilets.

Graywater is defined by both the county and the state as water coming from bathtubs, showers, bathroom sinks and washing machines. It does not include water from toilets, urinals, kitchen sinks, dishwashers or non-laundry utility sinks, which is often called blackwater.

The city and county of Denver was the first to adopt a similar permitting process in 2016, and did so after the state approved guiding regulations in 2015. The Pitkin County commissioners unanimously approved an ordinance last week that sets up the county’s permitting process, which is voluntary.

The city of Aspen also is considering adopting a graywater permitting system to complement its recently adopted water-efficient landscaping regulations.

Kurt Dahl, the county’s environmental health manager, said a 1999 statewide study found that typical indoor residential uses amounted to 69 gallons of water per person per day, and of that 28 gallons is graywater as defined by the state.

Graywater systems work by diverting household water away from its normal course — toward septic tanks and sewage systems — and into another set of pipes and storage tanks, where it sits until it is reused.

If the water is used for irrigation, the water must be filtered before storage and then, optimally, pumped out into a subsurface drip irrigation system. It cannot be applied via sprinklers.

If graywater is used to flush toilets, it must be disinfected and dyed before being sent to a toilet.

Single-family households can store up to 400 gallons of water a day in a tank for either irrigation or toilet flushing, and multi-family and commercial entities can store up to 2,000 gallons a day.

Graywater systems require double-piping of plumbing systems, which can be expensive to install in existing homes, and so may be better suited, at least economically, to new construction projects.

Brett Icenogle, the engineering section manager at the Colorado Department of Public Health, said Friday he was happy to see Pitkin County adopt a graywater permitting process, and he hopes other jurisdictions follow suit, even if current public demand seems low today.

“We don’t want to wait until there is a water shortage to put regulations in place,” Icenogle said.

The local permitting process begins with the county’s environmental health department, and also requires plumbing and building permits. If used for irrigation, it may also require a state water right.

Dahl served on a group that developed the state’s regulations, and he’d like to see other uses added to the state’s list, such as fire suppression.

“I want to get this to the point where using graywater is an option for everyone,” Dahl said.

Aspen Journalism is collaborating with The Aspen Times on coverage or rivers and water. More at http://www.aspenjournalism.org.

Ted Kowalski: We must act now to protect the future of the #ColoradoRiver #COriver

The Colorado River, not far below the Utah-Colorado state line, and flowing toward the lower basin. Photo credit: Aspen Journalism.

Here’s a guest column from Ted Kowalski that’s running in the Arizon Daily Star:

The Colorado River is the hardest-working river in the Southwest and an economic engine for the entire country.

But it is also a river facing a critical inflection point. Every drop of water that flows down the Colorado is already accounted for and due to a variety of factors — including a growing population and a changing climate — its flows are projected to decline over the next several decades.

These challenges exacerbate the fundamental problem facing the river: Demands on water outstrip supply.

Early forecasts for 2018 are already underscoring these challenges. Due to lower than average snowfall in the Rocky Mountains, the Colorado Basin River Forecast Center this month predicted that spring runoff into Lake Powell, the reservoir that supports the river’s Upper Basin, will be at a 47 percent of average.

The 2018 precipitation and runoff levels are threatening impacts that will reverberate across the western United States. The amount of water flowing into Lake Powell partially determines the amount of water to be released into Lake Mead, the Lower Basin reservoir that provides water to Arizona, Nevada and California.

Lake Mead’s elevation has been hovering at around 1,075 feet, the level at which the federal government imposes shortages on the Lower Basin states, for the last several years. However, with 2018 looking more and more likely to be drier and warmer than average, there is an increased likelihood of declared shortages in the Lower Basin in 2019.

The forecast is a sobering reminder that we need to take further action to secure the long-term future of the Colorado River Basin and the economies and environments that depend on it.

There’s still time for more snow to fall in the winter season, but it would take a significant uptick in precipitation levels to even reach average levels. We simply cannot rely on weather fluctuations to solve a problem that requires more fundamental, long-term solutions, including increased water conservation, flexible water management and better protection of healthy rivers and streams.

It is critical we act now to ensure the Colorado River Basin has the water supply needed to sustain the West’s growing population. Just think about the consequences of inaction — and the potential damage done. The river supports 16 million American jobs, generates $1.4 trillion in economic benefits annually, irrigates nearly 6 million acres of farmland, and supplies drinking water to about 40 million people.

Because the economic and environmental stakes are so high, we must enter a new phase of collaboration, innovation and flexibility when it comes to how we use and manage our water resources in the Colorado River Basin.

The good news is that throughout the basin, policymakers and water suppliers are rallying to address the escalating water-supply crisis through a series of water management strategies, system conservation programs and drought-contingency plans.

Negotiations on these actions are already occurring among the basin states, U.S. federal agencies and Mexico. These drought contingency plans are critical components needed to secure the future of the Colorado River, taking a proactive approach to ensuring that conservation will continue in the basin.

They also demonstrate that water users can develop innovative mechanisms to efficiently manage water supplies.

In Arizona, for example, lawmakers and water users are actively working to identify ways to cut back water use now in order to secure supplies over the long term. Arizona’s drought-contingency planning includes solutions that protect groundwater resources in the state, increases water management flexibility — and does not come at the cost of existing healthy river systems.

It is imperative that this plan, and others, are finalized and implemented in 2018.

The decisions we make in 2018 can protect future generations and revitalize the health of the Colorado River. At the Walton Family Foundation, we know it’s possible to implement these solutions. Moreover, we’re committed to supporting decisions to improve water management within the Colorado River Basin.

We must do more than address immediate challenges and mitigate the damage done during a dry winter. Investing in longer-term solutions and strategies will solidify programs and agreements that sustain the health of the Colorado River, and safeguard the livelihoods of millions of Americans for future generations.

Has the Central Arizona Water Conservation District exceeded it’s deal-making authority? #ColoradoRiver #COriver

The Central Arizona Aqueduct delivers water from the Colorado River to underground aquifers in southern Arizona. UT researcher Bridget Scanlon recommends more water storage projects like the aqueduct to help protect against variability in the river’s water supply. U.S. Bureau of Reclamation.

From The Arizona Star (Tony Davis):

Two former Arizona water directors told the State Auditor General’s Office last year that the agency that runs the Central Arizona Project exceeded its authority under state law.

The former directors, Rita Maguire and Herb Guenther, said recently that they told state auditors the Central Arizona Water Conservation District (CAWCD) legally overstepped its bounds.

The district did so, they said, by negotiating two rounds of water-storage deals with Southern California’s Metropolitan Water District (MWD) and a Nevada water agency in the 1990s and a third deal with the Southern California district in 2015.

The Arizona Department of Water Resources (ADWR) wasn’t informed of these deals until they had either been approved or until negotiations were far along, Maguire told the Star, adding that she’s concerned about this deal setting a precedent for future Colorado River users to ink similar deals on their own.

“It’s the state of Arizona’s entitlement to Colorado River Water. The CAWCD is a delivery agent, delivering the water on behalf of their customers,” Maguire said. “Their customers are only in three counties. If they can do that, what is to prevent other users from doing the same?”

Along the Colorado River in Arizona, plenty of parties have the same or even more senior rights to river water as the CAP does, said Maguire. They include the cities of Kingman and Yuma and the Yuma irrigation districts, among others.

“If they acted like CAWCD cutting deals with the Metropolitan Water District, that has ramifications that could affect the state,” she said. “That’s why it’s important that the state has oversight authority, to make sure everybody’s interests are attended to.”

Current ADWR Director Tom Buschatzke also raised concerns to auditors about what he termed a questionable action: that the Central Arizona Water Conservation District’s general manager disclosed confidential information from a district board executive session. Under state open meetings law, all information discussed in executive sessions must remain confidential, with limited exceptions.

The auditors didn’t agree with any of the concerns. The audit concluded in December that the Central Arizona Water Conservation District is generally following the law and other established procedures for how it spends money and manages the $4 billion CAP water project.

A CAWCD spokeswoman, Crystal Thompson, said the district properly coordinated its efforts on the 1990s deal with the state water department. The 2015 deal was never consummated, but the district fiercely defended its legality last year when it became publicly known.

This dispute is now being addressed in new legislation.

A bill introduced recently by state Sen. Gail Griffin, a Sierra Vista Republican, would require legislative approval of any transfer of Arizona water out of state.

It would also require ADWR and the three-county CAP water district to notify each other if they’re involved in any Colorado River water negotiations, including interstate agreements or agreements with the U.S. government.

Two weeks ago, the Star reported that the U.S. Bureau of Reclamation had told state auditors the CAP water district has illegally diverted Colorado River water that should have gone to Indian tribes to a related agency that recharges water into the aquifer for new development.

Pagosa Springs councillors approve seventh whitewater feature on the San Juan River

San Juan River from Wolf Creek Pass

From The Pagosa Sun (Marshall Dunham):

On Jan. 18, the Pagosa Springs Town Council unanimously voted to engage Wolf Creek Ski Area and Riverbend Engineering to complete a seventh whitewater feature on the San Juan River.

“Over the past several years, Wolf Creek Ski Area has donated heavy equipment and operators to build six of the seven whitewater features that were planned out many years ago through public input,” explained Town Manager Andrea Phillips to the council. “At this time, they are able and ready to complete the last feature, which is between the 1st Street bridge and Cotton Hole.”

Phillips stated that the feature would provide challenging condi- tions to kayakers and tubers.

She added that the project would involve concrete as well as stone work.

“In the past, the ski area has donated a lot of the equipment and the operators. The town’s covered the fuel costs as well as a pumper truck,” Phillips said. “This go around, the ski area is not able to provide as much of a donation as they have in the past. They’re still providing operators and assisting us with maintenance on our existing items and providing some of the equipment. However, they are asking for the town to step
up a bit more than we have on this other feature.”

Phillips went on to explain that $10,000 for construction manage- ment would be allotted, and that it would go to Riverbend Engineering.

Deep in the Grand Canyon, @USGS Scientists Struggle to Bring Back the Bugs — UNDARK

Via the USGS

From UNDARK (Martin Doyle):

This group was the “food base” team from the U.S. Geological Survey, led by Ted Kennedy and Jeff Muehlbauer. They had started their research trip at Lees Ferry, 87 miles upstream; they had already been on the river more than a week, and they looked it. Short-timers in the Grand Canyon, like me, wear quick-dry clothes and wide-brimmed hats only days or hours removed from an outfitter’s store in Flagstaff, Arizona. Long-termers like river guides and the USGS crew look like Bedouin nomads, with long-sleeved baggy clothes, bandannas, and a miscellany of cloths meant to protect every inch of skin from the sun — yet nevertheless with vivid sunburns, chapped and split lips, and a full-body coating of grime. Almost as soon as I got there, the ecologists wrapped up their work, packed their nets, buckets, tweezers, and other gear, and led me to their home: a flotilla of enormous motorized rubber rafts that held a mini-house of living essentials and a mini-laboratory of scientific essentials, all tightly packed and strapped to get through the rapids of the Grand Canyon.

Crystal Rapid via HPS.com