#ColoradoRiver Water Users Association Annual Conference recap #CRWUA2019 #COriver

Hoover Dam from the Arizona Powerhouse deck December 13, 2019. As John Fleck said in a Tweet, “Friends who have the keys showed us around this afternoon.” Thanks USBR.

Here’s a report from Andrew Davey writing for Nevada Today. Click through and read the whole article, here’s an excerpt:

Around this time last year, Commissioner Brenda Burman delivered this ultimatum to CRWUA attendees: “Close isn’t done, and we are not done. Only done will protect this basin.” This year, as in just yesterday, Burman said, “It was truly remarkable to have the divergent interests of the basin forge a compromise and make the difficult agreements to complete the DCP.”

And unlike last year, when Burman urged officials from across the Colorado River Basin to finish the DCP already, this year she urged patience on matters like renegotiating the 2007 agreement that turned Lake Mead into a sort of regional water bank. On that, Burman declared, “It’s not yet time to take up that task.”

Yet despite Burman’s more relaxed approach, some at CRWUA want to see more “fierce urgency of now”. While the DCP successfully fended off the threat of federal water rations, and while Upper Colorado River Basin snowpack is currently running 15% above average, ongoing legal concerns and the ever escalating threat of climate change may yet upend the delicate peace that the DCP has ushered in for now…

While Burman voiced confidence in the states’, municipal water agencies’, and Native American tribal authorities’ ability to cooperate, some of these very local officials were voicing notes of warning and caution. Shortly after Burman’s presentation on the main stage, Southern Nevada Water Authority (SNWA) Director of Water Resources Colby Pellegrino noted their use of data from the U.S. Geological Survey and UNLV’s Center for Business and Economic Research (CBER) showing less Colorado River water for everyone to work with in the next 50 years.

As Pellegrino described this challenge, “It’s a pretty severe stress test for our water resource portfolio.” Pellegrino then noted how SNWA and the larger community have already been rising to this challenge with conservation programs like outdoor watering schedules and turf removal. As Pellegrino put it, “There’s significant water savings to be achieved by changing the mindset of how we use it.”

Later in the day, I caught up with Pellegrino to talk some more about her presentation and the challenges that lie ahead for her agency and the entire region. When asked how SNWA plans to handle those future challenges, she replied, “Conservation is still right here, under our noses, the quickest and most cost effective way.”

[Friday], it was Interior Secretary David Bernhardt’s turn to make news here in Nevada. And make news he did, as Bernhardt announced the federal government will launch an early start of its review of the 2007 Interim Guidelines (as in, the 2007 agreement that launched the ICS program to manage the Lower Basin’s water supply).

Soon after his main floor presentation, Bernhardt spoke with reporters about this and other pressing water issues. On his announcement to jump-start review of the Interim Guidelines, Bernhardt said, “We have an opportunity right now. We have the people in place. We might as well build on the success we have here.”

So what can we expect in this review? And for that matter, what kinds of future changes might we expect in federal oversight of the Colorado River? When I asked Bernhardt whether he’d take into account climate science and the changing needs and consumption patterns of the increasingly urban American Southwest, he replied, “I’ve never taken a position of what we need to tell a city or county what they need to do.”

Yet as Bernhardt’s discussion with reporters continued, the conversation occasionally veered into other environmental matters. And when a couple reporters asked about the proposed oil and gas leases on public lands that have run into local opposition, including right here in Nevada, in the Ruby Mountains outside Elko and in parts of Lincoln County that supply drinking water for Mesquite, Bernhardt declared, “The president was clear when he ran for office what his policy is on energy. He supports an ‘all of the above’ approach.” Bernhardt also suggested these leases are required by federal statute, even though the Obama administration took a more cautious and targeted approach toward such fossil fuel extraction on public lands…

Funny enough, one of my takeaways from my conversation with SNWA’s Colby Pellegrino on Thursday was that regardless of what becomes of the long-fought pipeline plan, SNWA has enough water available to keep the Las Vegas region going for the next 50 years. Also, I noticed that regardless of the Trump administration’s curious comments on climate change and “all of the above” approaches to water infrastructure and fossil fuels, SNWA officials recognize the clear and present danger of climate change, and they’re already acting on it.

And it may not just be SNWA doing this. Even as Trump appointees are skirting around acknowledgement of climate science, fossil fuel pollution, ongoing regional tensions, or the reality of urban and suburban growth in the Colorado River Basin, federal civil servants continue to collect data, analyze trends, and manage the water we all share. We’ll talk more about that next week.

Still, there’s a rather large gap between the rhetoric and overarching policies of the Trump administration and the promises of strong climate action that U.S. Senators Elizabeth Warren (D-Massachusetts) and Bernie Sanders (I-Vermont), former Vice President Joe Biden, and the other 2020 Democratic presidential candidates are providing. And yet, we don’t hear as much about the Colorado River and our fragile water supply as you’d expect considering their environmental and geopolitical importance. Yet no matter how much we ignore it, all we have to do is glimpse at Lake Mead to remember how important it truly is to our very livelihood.

Click here to view the Tweets from the conference hash tag #CRWUA2019. Click here to view the @CRWUAwater Twitter feed.

Hoover Dam schematic via the Bureau of Reclamation.

From The Associated Press (Ken Ritter):

U.S. Bureau of Reclamation Commissioner Brenda Burman told federal, state and local water managers that abiding by the promises they made will be crucial to ensuring that more painful cuts aren’t required…

“We need to be proud of what we’ve done,” Burman told hundreds at the annual Colorado River Water Users Association conference at a Las Vegas Strip resort, while also warning of “tougher challenges in the future.”

Arizona, Nevada and Mexico will start taking less water from the river Jan. 1 under a drought contingency agreement signed in May. It followed lengthy negotiations and multiple warnings from Burman that if the seven states didn’t reach a deal, the federal government, which controls the levers on the river, could impose severe water restrictions.

California would voluntarily cut water deliveries if reservoir levels keep falling at the river’s largest reservoir, Lake Mead…

Cuts will most affect farmers in Arizona. The Central Arizona Project will stop storage and replenishment operations and cut water for agricultural use by about 15%. The agency gets more than half of Arizona’s entitlement of water from the Colorado River…

The drought contingency plan is a voluntary agreement to use less water than users are allowed, and its success is measured at the surface level of Lake Mead, behind Hoover Dam east of Las Vegas.

The agreements are designed to prevent a more drastic drought-shortage declaration under a 2007 pact that would cut 11.4 percent of Arizona’s usual river water allocation and reduce Nevada’s share by 4.3 percent. That amount of water, combined, would serve more than 625,000 homes.

California would reduce its Colorado River use by about 6 percent.

Due to a relatively wet winter, Lake Mead is now 40% full and Lake Powell, an upstream reservoir, is at 53% capacity, Bureau of Reclamation spokeswoman Patricia Aaron said. A year ago, Lake Powell was 43% full, and Lake Mead was at 38%…

Water managers have called the last 20 dry years a drought, but climate researchers warn the river will continue to carry less water in coming years.

“Respected climate scientists have conservatively estimated declines in river flows of 20% by the middle of the 21st century and 35% by the end of the century,” researchers Anne Castle of the University of Colorado Law School and John Fleck of the University of New Mexico wrote in a study released in November.

The report refers to a “structural deficit” under which states and Mexico are promised more water than the river usually carries and encourages the seven states to clarify rules for handling future shortages.

Brad Udall: “…latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with
@GreatLakesPeck

“Science be Dammed: How Ignoring Inconvenient Science Drained the #ColoradoRiver” — @R_EricKuhn/@jfleck

I finished Eric Kuhn and John Fleck’s new book in the hotel last night on my way to Las Vegas for the Colorado River Water Users Association Annual Conference.

It’s a page-turner that charts the history of the “Law of the River” and how politics and enthusiastic engineers that loved the big projects mostly trumped science in the debate and decisions since the Colorado River Compact negotiations. That trumping set the stage for we users of the Colorado River going forward. The book has praise for current decision makers and the deliberate effort to listen to the scientists regarding the hydrology of the river and the acidification in the basin due to the climate crisis.

Click here to order your copy of “Science be Dammed”.

Brad Udall: “…latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with
@GreatLakesPeck

The lost river — The Guardian #ColoradoRiver #COriver #aridification #Mexico

Morelos Dam. Photo credit American Rivers.

Here’s a update about Mexican efforts to restore the Colorado River Delta from Nina Lakhani that’s running in The Guardian. Click through and read the whole article. Here’s an excerpt:

…the river is dammed [by Mexico’s Morelos Dam] at the US-Mexico border, and on the other side the river channel is empty. Locals are now battling to bring it back to life.

There are few more striking examples of what has come to be known as “environmental injustice” – the inequitable access to clean land, air and water, and disproportionate exposure to hazards and climate disasters. Water in particular has emerged as a flash point as global heating renders vast swaths of the planet ever drier…

Currently the river flow in Mexico is 0.5 cubic metres per second, a fraction of what it once was. Another pulse flow to help restore the river’s estuary and wetlands could happen in 2021/22…

Because the 1944 treaty did not allocate Mexico any water for the river itself, the channel is mostly dry. The loss of the river in Mexico has has been devastating…

At the Morelos dam, located between Los Algodones, Baja California and Yuma, Arizona, the river is diverted to a complex system of irrigation canals which nourish fields of cotton, wheat, alfalfa, asparagus, watermelons and date palms in the vast surrounding desert valley. This is good for farmers – and less so for ordinary Mexicans.

Following the dry riverbed south towards the Gulf of California evokes an eerie sadness. The sound of gunfire in one wide, dusty section led to a couple from San Diego hunting wild pigeons, and a bucketful of feathered corpses. A few miles west along dirt farm roads, dozens of herons, egrets and ducks were staking out a wonderfully lush wetland – though it is only an accidental byproduct created by agricultural runoff from surrounding wheat and alfalfa fields.

Martha Gomez-Sapiens, a monitoring team member and postdoctoral research associate in the UA Department of Geosciences, stands on a riverbank next to willows and cottonwoods that germinated as a result of the pulse flow. (Photo: Karl W. Flessa/UA Department of Geosciences)

Five Years Later, Effects Of #ColoradoRiver Pulse Flow Still Linger — KUNC

From KUNC (Luke Runyon):

From inside a small airplane, tracing the Colorado River along the Arizona-California border, it’s easy to see how it happened.

As the river bends and weaves through the American Southwest, its contents are slowly drained. Concrete canals send water to millions of people in Phoenix and Tucson, Los Angeles and San Diego. Farms, ribbons of green contrasted against the desert’s shades of brown, line the waterway.

Further downstream, near Yuma, Arizona, the river splits into threads, like a frayed piece of yarn.

A massive multi-state plumbing system sends its water to irrigate the hundreds of thousands of farm acres in southern California and Arizona, hubs for winter vegetables, alfalfa, cotton and cattle.

When it hits the final dam, located on the U.S.-Mexico border, every drop has been claimed and put to use. In a typical year, what’s left of the river’s flow — promised to Mexico in a 75-year-old treaty — is sent to farm fields in the Mexicali Valley, and then on to the Mexican cities of Tijuana, Mexicali and Tecate.

All this reliance on an overallocated river has left its final hundred miles as the ultimate collateral damage. Since the early 1960s, when Glen Canyon Dam impounded the river near Page, Arizona, it has rarely reached the Pacific Ocean. The thread is frayed beyond recognition, leaving no water for the river itself.

“About 90 percent of the water is retained on the U.S. side and it’s used and diverted,” said Karl Flessa, a researcher at the University of Arizona. He studies the Colorado River Delta.

“In effect, one of the things we’ve done historically — not meaning to especially — what we’ve done is export some of the environmental consequences of water diversions,” Flessa said. “We’ve exported them to Mexico.”

The Colorado River’s inability to complete its journey from the Rocky Mountains to the Sea of Cortez has become one of its defining characteristics. Its historic delta, a haven for birds and mammals in the Sonoran desert, is a husk of its former self.

From the air, in a flight arranged by non-profit group LightHawk, the Colorado River Delta transitions from a jigsaw of farms to a staggering sprawl of muddy salt flats. (LightHawk receives funding from the Walton Family Foundation, which also funds KUNC’s Colorado River coverage.) The river’s historic channel in most parts through Mexico is nothing more than a sandy bed, scattered with saltcedar.

Where the river used to meet the ocean, tidal pools and drainages carve the sand and soil into organic patterns, like the cross-section of a lung.

Within the last twelve years, both the U.S. and Mexico have acknowledged the delta’s problems, signing agreements to commit both water and funding to restoring it to some semblance of its former self.

The splashiest of those efforts took place five years ago this spring, and left a lasting imprint on those who witnessed it.

The pulse flow

Around 8 o’clock on a Sunday morning in March 2014, water began spilling through Morelos Dam on the U.S.-Mexico border. The release was a culmination of years of negotiation between the U.S., Mexico and environmental organizations.

It was known as the pulse flow — flujo pulso in Spanish.

“You think of it as this wall of water that’s going to come down, but really it was this creeping tongue of water across the sand,” said Jennifer Pitt, who worked for the Environmental Defense Fund at the time, and now directs the Colorado River program for the National Audubon Society. Both groups receive Walton Family Foundation funding. Pitt was a key negotiator to make the pulse flow possible…

It took a few days after the dam opened for the water to arrive at the bridge, where Pitt and her colleagues gathered to wait. About 70 people in garden chairs sat in anticipation. A community clean-up a few days prior left the riverbed scrubbed of trash and debris.

For many young people, it was the first time they had ever seen water flowing in this stretch of the Colorado River. For older residents, it had been decades since they saw this much water here.

“They started getting up just one by one, people coming over to the water and getting down on their hands and knees and just touching it,” she said. “It was like the arrival. The great arrival of the river.”

A spontaneous festival started, complete with music, food vendors, horses and boats.

“I’ve spent 20 years thinking about how we can restore the Colorado River from where it dries out to where it reaches the sea,” Pitt said, “And in all of that thinking have never imagined that this site could bring so many people in as a magnet for people to enjoy something.”

Within weeks the flow was soaked up by depleted soils, though it did eventually reach the Pacific Ocean. From where Pitt and I are standing at the bridge in early December 2018, you’d never know the West’s mightiest river was supposed to flow here.

The pulse flow was about 105,000 acre-feet of water, enough to turn the channel again into a river for a few weeks. One acre-foot generally provides enough water for two average American households for a year. Historically more than 12 million acre-feet flowed into the delta each year…

Combined, that amount of water led to a green up along the river corridor, and sustained more than 275,000 new trees, according to a December 2018 report from the International Boundary and Water Commission.

The pulse flow’s biggest effects were short-lived. Both the green up and increases in certain species dropped again after the water stopped flowing.

The pulse flow’s biggest effects were short-lived. Both the green up and increases in certain species dropped again after the water stopped flowing.

A study from U.S. Geological Survey scientists confirmed that. It found that the amount of water in the pulse flow was too small to change the channel in a significant way, or scrub the riverbed, which would’ve happened during a more natural spring flood when flows would be much higher.

Because of the delta’s low water table, a lot of water seeped into the ground before it could do any good on the surface to help establish new wildlife habitat in expanded restoration areas. It was an experiment, said University of Arizona researcher Karl Flessa. Scientists experiment all the time, chart the results and move on.

Does he think the delta will ever see another pulse flow on the scale and magnitude of the one seen in 2014?

“Probably not,” he said. “Because you can get the water to do more restoration work by delivering it in smaller doses as it were, and delivering it to the right places where the vegetation can really take advantage of it.

“I think restoration, like any other activity with water, we’re really obliged as a society to be as water efficient as possible.”

‘Mission-Oriented’ #ColoradoRiver veteran takes the helm as the US Commissioner of International Boundary Waters Commission — @WaterEdFdn #COriver #aridification #WomenInWater

From the Water Education Foundation (Gary Pitzer):

Western Water Q&A: Jayne Harkins’ duties include collaboration with Mexico on Colorado River supply, water quality issues

Jayne Harkins, the U.S. Commissioner of the International Boundary and Water Commission. (Image: IBWC)

For the bulk of her career, Jayne Harkins has devoted her energy to issues associated with the management of the Colorado River, both with the U.S. Bureau of Reclamation and with the Colorado River Commission of Nevada.

Now her career is taking a different direction. Harkins, 58, was appointed by President Trump last August to take the helm of the United States section of the U.S.-Mexico agency that oversees myriad water matters between the two countries as they seek to sustainably manage the supply and water quality of the Colorado River, including its once-thriving Delta in Mexico, and other rivers the two countries share. She is the first woman to be named the U.S. Commissioner of the International Boundary and Water Commission for either the United States or Mexico in the commission’s 129-year history.

The IBWC, whose jurisdiction covers the 1,954 miles of border from San Diego to the Gulf of Mexico, is responsible for applying the boundary and
he United States and Mexico, and settling differences that may arise in their application.

The IBWC is recognizable to many people as the implementing body for the additions to the 1944 U.S.-Mexican Water Treaty on the Colorado, Rio Grande and Tijuana rivers known as Minutes. In 2017, the latest addendum, Minute 323, built on previous agreements that specified reductions in water deliveries to Mexico off the Colorado River during a shortage and allowed Mexico to store water in Lake Mead, the nation’s largest reservoir which sits near Las Vegas.

The New River, a contaminated waterway that flows north from Mexico, spills into the Salton Sea in southwestern California’s Imperial Valley. Transborder pollution is among Jayne Harkins’ priorities as U.S. IBWC Commissioner. (Image: U.S. Bureau of Reclamation)

There are other issues, as well. Transborder pollution – from the New River spilling into the Salton Sea and from the Tijuana River fouling San Diego County beaches – is on her radar. Last year, the San Diego Regional Water Quality Control Board sued the U.S. section of the IBWC, claiming it is violating the Clean Water Act by not monitoring or stopping the untreated waste flowing to the Pacific Ocean from the Tijuana River that has caused beach closures in San Diego County.

Harkins, who lives in El Paso, Texas, spoke recently to Western Water about her new mission, transborder pollution and addressing Colorado River shortages with Mexico. The transcript has been lightly edited for space.

You are the first woman to be selected as IBWC commissioner. Do you see that as a significant accomplishment?

Yeah, I do. It is [significant] but I wish it weren’t. It should have happened a long time ago from my perspective. For me, you just plow on and get work done.

What is the significance of the IBWC and how its mission affects the various stakeholders?

We started as the International Boundary Commission and, of course, that is more straightforward. They work to demarcate the boundary, [and] maintain our boundary monuments.

Jayne Harkins (seated, far left), as executive director of the Colorado River Commission of Nevada, was one of the signers in 2017 of domestic agreements that were part of Minute 323, the addendum to the 1944 U.S.-Mexican Water Treaty. (Image: U.S. Bureau of Reclamation)

In 1944, of course, we got the treaty with Mexico that went beyond boundary stuff. That is what distributed waters between the United States and Mexico on the Colorado River. A part of that treaty authorized the joint construction and operation of international storage dams on the Rio Grande, and there is some discussion on a preferential solution to the issue of border sanitation problems.

I think a lot of what IBWC can do in both the U.S. and Mexico is bring all the stakeholders together into binational meetings to talk about the data we have, what are we lacking and then try to resolve issues.

What are your priorities as commissioner?

My priority is border sanitation. We have a number of areas with border sanitation issues and that’s one to try and figure out and see what we can do. Also, we have our treaty water deliveries and water quantity and quality responsibilities, depending on what the minutes require. We have those pieces that we need to make sure get done. We have got infrastructure issues on some of our dams and we just need to be operating and maintaining older infrastructure and make sure we are repairing and replacing as needed.

What is the IBWC’s role in water quality issues?

We are coordinating with others because there are some things that we can’t do that others can, and so we are trying to bring a coordinated effort among the federal U.S. entities. With Mexico, it’s what are the appropriate entities, federal and state, that they have to have. Each one of these is a local issue and we’ve got to bring in the local stakeholders because they have an interest as well. Some solutions may include infrastructure on both sides of the border. A number of studies regarding infrastructure improvements have been completed or are underway. We are working with local, state and federal agencies, as well as Mexico, to address the Tijuana River sanitation issue in a cooperative manner.

This has been ongoing for a long time. As I looked at it, I’m like, “Are things better than they were?” If you look at the data, even New River stuff [the New River flows from Mexico into California’s Imperial Valley and toward the Salton Sea], it’s much better than it was 20 years ago. If you look at the numbers overall, it’s not good enough. It’s not like the discharges meet U.S. standards and that’s what people in the U.S. are looking for. We are trying to help be a convener of folks to make sure we know what the data looks like, to make sure we know fact from fiction and bring people together who can perhaps bring some money to this and work with Mexico to see who can do what parts.

The water quality issues on the Colorado River are outlined in Minute 242 as related to salinity requirements. Minute 323 established a Salinity Work Group to minimize the impact of Minute 323 activities on salinity and to undertake cooperative actions like modernizing salinity monitoring equipment.

How is the IBWC involved with drought planning efforts?

Colorado River water released from Morelos Dam, along the border with Mexico, flows downstream into the Colorado River channel in March 2014 to benefit the environment as part of the cooperative measures agreed to by the United States and Mexico under Minute 319. (Image: U.S. Bureau of Reclamation)

We are not specifically engaged in the Lower Basin Drought Contingency Plan, but we are very interested in it and monitoring it and checking in with folks about what’s going on. Mexico is very interested because they have agreed to sharing shortages when the Lower Basin is in shortage. If there is a Lower Basin Drought Contingency Plan, Mexico has their Binational Water Scarcity Plan and they would take some additional reductions. So from the standpoint as to how we implement Minute 323 and what we need to do with sharing information with Mexico, that’s our part of the involvement.

The Binational Water Scarcity Contingency Plan is essentially how the DCP would be applied to Mexico.

What’s the status of Minute 323 implementation?

There are a number of conservation projects in Mexico that are wrapping up. We are involved in the verification that they got constructed. We will work with Mexico on the quantity of water that’s being conserved. As construction gets done, those projects are funded by some of the U.S. stakeholders, and we move that money over to Mexico so they can pay the contractors.

A recent report provided findings of the 2014 pulse flow of more than 100,000 acre-feet of water into the riparian corridor of the Colorado River Delta implemented under Minute 319. How will that inform future efforts?

We learned many things about water delivery methods, infiltration, irrigation techniques and groundwater – information that will guide our Minute 323 environmental work. This report provides solid scientific information about our restoration efforts. The findings will help us apply environmental water more effectively in the future.

Restoring the #ColoradoRiver: Bringing New Life to a Stressed River — Yale 360 #COriver #aridification

Colorado River Delta

From Yale 360 (Jim Robbins). Here’s an excerpt click through for the photos and to read the whole article:

The Colorado River has been dammed, diverted, and slowed by reservoirs, strangling the life out of a once-thriving ecosystem. But in the U.S. and Mexico, efforts are underway to revive sections of the river and restore vital riparian habitat for native plants, fish, and wildlife. Fifth in a series.

From the air, the last gasp of the Colorado River is sudden and dramatic. The pale green river flows smack into the Morelos Dam on the U.S.-Mexico border, and virtually all of it is immediately diverted into a large irrigation canal that waters a mosaic of hundreds of fields — alfalfa, asparagus, lettuce, and other vegetables, their vivid green color clashing against the sere desert. The slender thread of water that remains in the Colorado’s channel continues to flow south, but is soon swallowed up by a sea of sand, far short of its delta, which lies 100 miles farther on.

The Colorado River once surged through the delta during high flows, carrying so much water at times that shallow draft steamboats chugged hundreds of miles up the river into the U.S. with loads of freight. The water in the delta nourished a vast fertile landscape, a fitting end to a river known as the Nile of North America.

“The river was everywhere and nowhere,” the naturalist Aldo Leopold wrote during a 1922 canoe trip to the delta, describing the waterway as it ebbed, flowed, braided, and stalled into pools, nourishing a rich and diverse ecosystem of “a hundred green lagoons,” a “milk and honey wilderness” with thick stands of cottonwoods and willows that provided habitat for hundreds of species of birds. The delta’s marshes, mudflats, and white sand beaches were home to clapper rails, bitterns, mallards, teal, and clouds of egrets.

Bobcats, puma, deer, and wild boar wandered the delta’s forests. Leopold was searching for the jaguar that roamed there, but didn’t see any…

Morelos Dam. Photo credit American Rivers.

As a natural river, before it was dammed, the Colorado was a massive, dynamic waterway. It flowed from elevations above 14,000 feet in the Colorado Rockies, then dropped to sea level, which meant that it moved at high water with tremendous force, liquid sandpaper carving out red rock canyons. It flooded the desert plains, carving new channels and braids with every inundation. When it receded, it left behind a mosaic of fecund marshes, wetlands, and ponds.

In its natural state, the Colorado had more extreme flows than any river in the U.S., ranging from lows of 2,500 cubic feet per second in the winter to 100,000 cubic feet per second in the summer. In 1884, an all-time historical peak flow reached 384,000 cubic feet per second in Arizona.

But extreme flows are too capricious to support a civilization, so over the past century or so humans have built a network of expensive dams and reservoirs, pipelines, canals, flumes, and aqueducts to tame and divert the flow. Yet these projects also strangled the life out of a once-thriving ecosystem. By design, the river will never again function as a free-flowing stream.

Now, however, experts and environmentalists are rethinking this technological marvel of a river, and looking at ways a natural Colorado can flourish — to some degree, and in some places — with the permission of the engineers. One of those places is in the delta.

The water that flowed in the once-lush delta has been replaced by sand, and the cottonwoods and willows have surrendered their turf to widespread invasive salt cedar and arrowweed. Without the river and its load of nutrients, marine productivity in the Gulf of California — where the Colorado River once ended — has fallen by up to 95 percent. But despite the dismal forecast for the future of water on the Colorado, some conservationists are hoping to return at least a portion of the delta to its former glory.

Point 24 in the Colorado River Delta, September 12, 2016. Photo credit The Nature Conservancy.

“We are trying to restore a network of sites that creates a functional ecosystem,” said Francisco Zamora, who manages the project for the Sonoran Institute. “We’ve acquired water rights, but use them for habitat instead of cotton or wheat.”

The delta is one of a disconnected series of restoration projects that government agencies, local groups, and environmental organizations are undertaking along the Colorado. Numerous efforts are focused on tributaries to the main stem of the river, seeking to enhance resiliency by increasing the flow of water and protecting and restoring riparian habitat for fish and other wildlife.

For example, a coalition of groups — including state agencies, nonprofits, and the Arizona cities of Buckeye and Agua Fria — have been removing invasive salt cedar, planting native species, and building levees to reclaim a 17-mile stretch of the Gila River. Invasive salt cedars are a region-wide problem on the lower Colorado, with a single tree sucking up 300 gallons a day. The invasive forest on this stretch of the river uses enough water to serve 200,000 households.

In the upper basin, meanwhile, a number of groups and local landowners are working to restore a 15-mile-long floodplain with globally significant biodiversity on a narrow section of the Yampa River, another Colorado tributary. Called Morgan Bottom, the section has been damaged by deforestation and poor agricultural practices, threatening bald eagles and greater sand hill cranes, as well as a rare riparian forest of narrowleaf cottonwood and red osier dogwood.

But there are limits to how natural the Colorado River can become, especially along the river’s main stem. “We should not kid ourselves that we are making it natural again,” said John Fleck, the director of the University of New Mexico’s water resources program and the author of a book about the restoration of the Colorado. “We are creating an intensively managed system to mimic some nature because we value it.”

Because of the Colorado’s extensive infrastructure, serious disruption of the river’s ecology is inevitable.

Indeed, some of the remaining naturalness on the Colorado is, paradoxically, because of the human-made system. “The geography of the Colorado gives it hope because L.A. and southern California, which everybody loves to hate, guarantee that a lot of water stays in the system through the Grand Canyon,” says Jack Schmidt, a professor at Utah State University and a member of the Colorado River Research Group. “The best friend endangered fish ever had in the Colorado River Basin is that giant sucking sound” of California withdrawing water.

Widespread protection efforts are focused on native fish in the Colorado. The river once was home to an unusual number of endemic fish. But dams, irrigation, and the introduction of bullhead, carp, and catfish did them in. While the upper basin still has 14 native fish species, the lower basin, according to one study, “has the dubious distinction of being among the few major rivers of the world with an entirely introduced fish fauna.”

The Colorado pike minnow — something of a misnomer for a fish that historically grew to 6 feet in length and weighed up to 80 pounds — once swam through the entire system from Wyoming to Mexico. It is now listed as endangered, with two distinct populations remaining in the upper Colorado and the Green River.

The humpback chub lived in various canyon sections, and though once seriously endangered, it has fared better in recent years through transplantation efforts, growing from 2,000 to 3,000 fish to 11,000. Officials say it may soon be taken off the endangered list.

Beginnings. Photo: Brent Gardner-Smith/Aspen Journalism

Razorback suckers, once common, are now rare. The bonytail, a type of chub that is one of North America’s most endangered fish, no longer exists in the wild. A handful of these fish exist in hatcheries, and attempts are underway to restock them in the river throughout the basin.

Because of the Colorado’s extensive infrastructure, serious disruption of the river’s ecology is inevitable. Dams trap most of the river’s sediment in reservoirs, which means there is no material to rebuild beaches, sandbars, and important fish habitat downstream.

Dams also deprive the river downstream of nutrients, such as phosphorous and nitrogen, and stratify water temperatures. The native fish in the Colorado adapted to a wide range of temperatures, from cold to very warm. They also evolved to tolerate high flood flows along with extremely dry periods. Now, the water is cold in the summer for miles below the dams, and the humpback chub and other fish that had adapted to a range of water temperatures and flows suffer.

Something called hydro-peaking also has had serious impacts on the food web. Dams generate power according to demand. As people come home from work and switch on the stove, air conditioning, and lights, demand soars and dams release more water to produce power. “Prior to the construction of dams, there were almost no major daily changes in river levels,” said David Lytle, a professor of integrative biology at Oregon State University. When fluctuations in water levels occur, they “can interrupt the egg-laying practices of some species. It’s a serious problem.”

Insects lay their eggs just below the water level, and if levels drop rapidly it can dry them out. A recent study found that below the Hoover and Glen Canyon dams, there was a complete absence of stoneflies, mayflies, and other species — insects that are vital food for fish, bats, birds, and other creatures.

Because of the ecological effects of the Glen Canyon Dam, the Grand Canyon stretch of the Colorado is one of the least productive sections of river in the world. The Colorado here will always be highly unnatural, a novel, human-created ecosystem with some natural elements.

Today, there is a large and growing backlash against dams in America and elsewhere as the immense damages they have inflicted on rivers become manifest. Few dams, though, are as reviled as the Glen Canyon, which was built in 1963 and took 17 years to fill Lake Powell.

Before the Glen Canyon was dammed, those who saw it say it was not unlike the Grand Canyon, with towering walls of red, tan, and ochre. Early Native American sites were plentiful. Environmental activist Edward Abbey decried the dam, and in his novel the Monkey Wrench Gang fantasized about using houseboats packed with explosives to blow it up. In 1981, members of Earth First!, a radical environmental group with a connection to Abbey, rolled a black plastic “crack” down the face of the dam to symbolize its demise.

Changes in the northeastern reaches of Lake Powell are documented in this series of natural-color images taken by the Landsat series of satellites between 1999 and 2017. The Colorado River flows in from the east around Mile Crag Bend and is swallowed by the lake. At the west end of Narrow Canyon, the Dirty Devil River joins the lake from the north. (At normal water levels, both rivers are essentially part of the reservoir.) At the beginning of the series in 1999, water levels in Lake Powell were relatively high, and the water was a clear, dark blue. The sediment-filled Colorado River appeared green-brown. To see the complete series go to: earthobservatory.nasa.gov/WorldOfChange/LakePowell. Photos via NASA

Removing the dam was part of the reason the Glen Canyon Institute was formed, but activists have now dropped that idea, says Rich Ingebretsen, a Salt Lake City physician who founded the group. Today, he advocates draining Lake Powell to fill Lake Mead, which is downstream and where the need for water is by far the greatest. The “Fill Mead First” campaign would restore a free-running Colorado River to what was once Lake Powell.

“You’d get much of Glen Canyon back,” said Ingebretsen. “A free-flowing river through the Grand Canyon means you’d restore the river — riparian zones, animals that belong there, a beautiful canyon with arches and bridges and waterfalls. Much of that would come back very quickly.” There would also be increased water in the river, he says, because so much of the Colorado is now lost from Lake Powell; scientists estimate that the lake loses three times Nevada’s allotment of water because of evaporation. As levels in Lake Mead drop due to prolonged drought, a growing number of people are taking this idea more seriously.

Paradoxically, two of the Colorado River’s most important wetlands for wildlife are the product of runoff from irrigated farm fields — and are now at risk from a changing climate and agreements to reduce water use.

In the Sonoran Desert of northwestern Mexico, the 40,000-acre La Cienega de Santa Clara wetland was inadvertently created in the 1970s when U.S. officials built a canal to dispose of salty wastewater from agricultural fields in Arizona. As the water began spilling into the desert, myriad forms of life began to appear. Now its cattail-studded marshes and mudflats are considered one of the most important wetlands in North America, home to 280 species of birds — including the endangered Ridgeways rail — on what was once hard-baked desert.

Meanwhile, in California, the Salton Sea was once a shallow inland lake whose levels routinely fluctuated. In 1905, an effort to increase Colorado River flow into the Imperial Valley led farmers to allow too much river water into their irrigation canal, overwhelming their system; for two years the water poured into the 35-mile-long, 15-mile-wide Salton Sea and expanded it.

But as less water becomes available to agriculture and rising temperatures cause more water to evaporate, scientists are concerned that these wetlands will dry and shrink faster than they already have. A 2003 agreement, for example, allows agricultural water in the Imperial Valley to be sent to San Diego for municipal uses. That could cause water levels in the Salton Sea to drop by more than 40 percent, dramatically reducing bird habitat and increasing toxic dust because wetlands would dry out. Local, state, and federal officials have devised a plan — still not fully funded — to restore 15,000 acres of wetlands, at a cost of more than $700 million.

The largest project to restore some semblance of nature to the Colorado River, though, is in the delta. An unusual agreement in 2012 between the U.S. and Mexico, called Minute 319, mandated that the two countries would provide water and funding to revive sections of the delta and release a one-time pulse of 105,000 acre-feet to again connect the river to the delta temporarily. Scientists would then study the effects.

In 2014, for the first time in decades, the river flowed again in Mexico — for eight weeks. San Luis Rio Colorado — once a Colorado River town, but now a dusty desert settlement — became a river town for two months, to the delight of locals, many of whom had never seen the river. The pulse offered a glimpse of what reclamation efforts might look like. “It gave us an idea of how the river behaves, and the best sites for restoration,” said Zamora.

Martha Gomez-Sapiens, a monitoring team member and postdoctoral research associate in the UA Department of Geosciences, stands on a riverbank next to willows and cottonwoods that germinated as a result of the pulse flow. (Photo: Karl W. Flessa/UA Department of Geosciences)

Minute 319 and its 2017 replacement, Minute 323, have funded the restoration of sections of the river. A group of nonprofits — including the National Audubon Society, the Sonoran Institute, The Nature Conservancy, and a Mexican group called Pronatura Noroeste — is working on a project called Raise the River to revive a significant swath of the delta.

In 2008, the group secured rights to 1,200 acres along the desiccated river channel. Since then, local residents have torn out acres of salt cedar and planted irrigated fields of cottonwood, willow, and other endemic species — more than 200,000 trees in all. A small supply of water mandated by the treaty, along with excess water that flows off of irrigated fields, have been dedicated to the restoration.

On a recent visit, I joined Zamora and botanist Celia Alvarado on a short boat ride to Laguna Grande, a 6-mile section of restored river and estuary. We skimmed across still water the color of weak tea, minnows darting away from our paddles. Thick groves of cottonwoods and willows lined the river. Zamora remarked that bobcats and beaver lived there now, along with blue grosbeaks and yellow-billed cuckoos. “Impacting the target species is key,” he said.

And what about the jaguar? I asked. It has not returned, he said. Will it come back?

“Yes,” said Zamora, smiling. “Someday. If they allow me to introduce them.”

For A Few Weeks The #ColoradoRiver Reached The Ocean. Will It Happen Again? — @LukeRunyon (@KUNC) #COriver

Here’s a look back at Minute 319 and the Colorado River pulse flow from Luke Runyon that’s running on the KUNC website. Click through and read the whole article. Here’s an excerpt:

In 2014, the Colorado River did something it hadn’t done in decades. For a few short weeks that spring, the overdrawn, overallocated river reached the Pacific Ocean.

Instead of diverting the river’s last bit of water toward farm fields, the final dam on the Colorado River at the Mexican border lifted, and water inundated nearly 100 miles of the dry riverbed. It was called the pulse flow, meant to mimic a spring flood.

In 2010, an earthquake in northern Mexico set in motion a big change in how people think about the lowest reaches of the Colorado River. The quake destroyed irrigation canals, leaving farmers unable to use all of their water. As the result of an emergency agreement, Mexico began storing its share in U.S. reservoirs. After another international agreement, Mexican and American officials decided that, as an experiment, the surplus water should temporarily flow into the river’s driest reaches.

The water’s life-giving effects spilled beyond the river’s banks. Kids who’d never seen it in its natural channel, splashed and played. Spontaneous festivals came to life. Birds returned, and trees and marshes greened up.

But the moment was fleeting. Within a few months, the majority of the delta was dry once again.