It’s a wrap! We’ve just enjoyed two packed days of planning strategies to continue our work to restore water and life in the #ColoradoRiverDelta. After listening to the progress updates, “tales from the field”, ideas, back-stories and passionate presentations, it is clear that we have an amazing coalition of partners! Here’s to Sonoran Institute, Pronatura Noroeste, National Audubon Society, The Nature Conservancy, Save the Colorado River Delta, The Redford Center — and especially our generous supporters and funders. Here’s to an exciting 2017 in support of the Colorado River Delta and surrounding communities!
Historic cooperation results in hope for environmental restoration
Cooperation between the U.S. and Mexico governments, supported by a coalition of non-profit organizations, is demonstrating the power of community to achieve environmental benefits, as recently released scientific findings in the Colorado River Delta have documented.
The Colorado River is one of the world’s most endangered rivers. Dams and water diversions for farms and cities upstream in both countries deplete the water before it meets it natural end in the Gulf of California. Its delta, once a vibrant habitat for wildlife and migrating birds, is now dry, as the river stops 70 miles short of the sea. A unique and landmark bi-national collaborative effort to revive the dry delta landscape on behalf of the environment came together in 2014, followed by an engineered release of water into the region – known as a ‘pulse flow’ – which flooded the dry Colorado River Delta and reconnected habitats, wildlife, and local communities with the river for the first time in decades.
On October 21, the International Boundary Water Commission (IBWC) published the “Minute 319 Colorado River Limitrophe and Delta Environmental Flows Monitoring Interim Report“, an interim report on the environmental impact of this 2014 pulse flow, plus subsequent supplemental deliveries of water through December 2015. Research on the effects of the 2014 pulse flow will continue through 2017 with a final report due in June 2018. A binational, University of Arizona-led team of scientists and environmental experts – including those from The Nature Conservancy, Pronatura Noroeste and the Sonoran Institute – contributed to the report. These three organizations are all members of Raise the River, a coalition of conservation organizations working to protect and restore the Colorado River Delta. Other members of Raise the River include the National Audubon Society, The Redford Center, and Restauremos El Colorado.
The IBWC and its Mexican counterpart (CILA) are U.S. and Mexican federal agencies that negotiate and implement binational water treaties and water allocations. In 2012, the IBWC and CILA successfully negotiated Minute 319, an amendment to the 1944 U.S.-Mexico Water Treaty (modifications of treaties are referred to as minutes). Minute 319 included the authorization of environmental flows of water into the Colorado River Delta from 2013 to 2017, and was the first binational agreement in the world to dedicate flows for environmental purposes. The result of extraordinary binational collaboration among government agencies, conservation organizations, water users, and other Delta stakeholders, Minute 319 provides multiple benefits for water users on both sides of the border. In addition to the water flows, it more broadly provides for the U.S. and Mexico to share surpluses in times of plenty and reductions in times of drought, offers incentives for leaving water in storage, and conserves water through joint investments in projects from water users in both countries. The agreement also served to recognize the Colorado River Delta as a place of global ecological significance.
Following the signing of Minute 319, more than a year of work by a multinational, multidisciplinary, multi-organizational science team went into preparations for designing the pulse flow and establishing the monitoring requirements for its hydrologic and ecological responses. Then, between March 23 to May 18, 2014 nearly 106,00 acre-feet of water was released from Morelos Dam into the dry Delta, flooding more than 4,000 acres of riverbed landscape, and once again – briefly – the river met the sea for the first time since 1997. (An acre-foot is the volume of water required to cover one acre of land to a depth of one foot – approximately the amount of water a family of five uses in one year.)
Following the pulse flow, small increments of water—known as base flows—were periodically released into the delta to maintain the pulse flow’s effects.
“Like the pulse flow itself, this report was a binational collaboration. Scientists from government agencies, academia, and conservation organizations on both sides of the border contributed to the monitoring efforts,” said Eloise Kendy, a senior freshwater scientist with the North America Water Program of The Nature Conservancy.
The team, and the study
The monitoring team includes more than 21 scientists from universities, government agencies and nongovernmental organizations from both Mexico and the U.S., including El Colegio de la Frontera Norte, Pronatura Noroeste, The Nature Conservancy, Sonoran Institute, the Universidad Autónoma de Baja California, the University of Arizona, the U.S. Geological Survey and the U.S. Bureau of Reclamation.
The study results released on October 21, 2016 detailed the increase in birds, plants, and groundwater in the delta since the pulse flow, which signifies that these water flows in the Colorado River Basin could help restore the native environment and bring back native flora and fauna to the arid Colorado River delta.
“The findings confirm that what scientists and conservationists are doing for the delta is working”, said Jennifer Pitt, Director of the National Audubon Society’s Colorado River Project, who has been among the leaders of the delta restoration effort for many years. “It’s proof positive that adding a little water back into that ecosystem can work”.
- Plants: Native plant life returned, with a 16% increase in density of green vegetation recorded by satellite imagery in the floodplain one year following the pulse flow.
- Although greenness declined in 2015, it was still greener in 2015 compared to 2013, indicating that the single pulse flow in 2014 stimulated plant growth for at least one year.
- Native plants – including cottonwood, mesquite, and willow seedlings – grew much better in restoration areas where non-native vegetation was removed before the pulse flow, as well as in areas actively managed following the primary release of water.
- Birds: Greater bird abundance and diversity was recorded, with both the number and diversity of bird species increasing significantly from 2013 to 2015.
- This was particularly notable where trees were planted, with the highest concentrations in the restoration sites.
- Of the 19 species monitored for conservation interest, an increase of 49% was recorded from 2013 to 2015.
- Groundwater: Results indicated that pulse flow also recharged groundwater in the delta, an important resource for some native tree and shrub species.
- Community: Beyond wildlife, the pulse brought together local residents, from older generations who remembered the river, to younger generations who had never before seen it flow.
“The social response—that was amazing,” says Dr. Osvel Hinojosa Huerta, Director, Water and Wetlands Program of Pronatura Noroeste. He recalls what happened in the border city of San Luis Río Colorado, where the namesake river had largely vanished. “When the river came back, it was like a party in town every day. Thousands of people were celebrating in the river.”
- Precedent-setting: The study results will be used to inform future bi-national cooperation efforts on behalf of the river. The science team learned a great deal about how water moves through the delta ecosystem and is, for the first time, equipped with data-driven recommendations for future restoration activities. Notably, the pulse flow is setting a precedent for water-sharing agreements globally, as well as inspiring water rights advocates far beyond the region. Raise the River coalition members Pitt and Hinojosa Huerta say that groups involved in river restoration from as close to home as the Rio Grande to as far as Central and Eastern Asia have reached out to express interest in the water sharing concept.
Small amount, large impact
Less than 1 percent of the Colorado’s historic flow to the delta was returned by the flows sanctioned under Minute 319, yet the strategic timing and placement of the water supported the thesis that a small amount of water is sufficient to restore crucial habitat for the birds and wildlife that have historically lived in the delta. It also provided lessons learned to be applied to future water deliveries.
“The most important lesson we learned is that a relatively tiny bit of water can go a long way toward restoring the Delta” added Kendy. “Water expeditiously applied to prepared floodplain areas has established new native trees that are already way over my head”.
The work continues
With Minute 319 concluding in 2017, researchers and coalition members of Raise the River are currently negotiating a successor agreement to support continued cooperative work between Mexico and the U.S., with the hope of having this in place by the end of this year. Just as the report showed that active restoration sites achieved the highest success rate, the restoration of the delta is a long-term process.
“This project demonstrates that a relatively small amount of water, particularly when coupled with active restoration, can provide significant benefits to rivers with reduced flows,” states Karen Schlatter, Adaptive Management Specialist for the Colorado River Delta Program, Sonoran Institute. “When diverse stakeholders collaborate on Colorado River water management, governments, communities, and the environment have much to gain.”
The report results show that the flows created new habitat, increased bird diversity, and also provided a meaningful reconnection of local communities to the environment, offering hope for the region.
Working together, greater good can result, as the recent monitoring report on the Spring 2014 “pulse flow” of water into the Colorado River Delta has validated.
Raise the River Coalition Partner Reports:
- National Audubon Society, October 21, 2016 — Pulses of Water Bring Life to the Famished Colorado River Delta;The Colorado River is one of the world’s most endangered rivers. But recent pulses of water have started to bring life back to the famished region.
- Sonoran Institute, October 26, 2016 — Ever wonder what Minutes have to do with Water?There’s been a lot of news coverage on a recent report about our historic work in the Colorado River Delta. This report answers your FAQ’s and gets you up to speed with this groundbreaking environmental project.
- The Nature Conservancy, October 31, 2016 — Top Four Scientific Results of the Pulse Flow; Highlights of the Interim Report issued by the International Boundary Water Commission, United States and Mexico sections, outlining the scientific results to date of the 2014 “pulse flow” of water into the Colorado River Delta.
- Additional media coverage can be found on the Raise the River website, in our “Press” sectio
Two growing seasons after the engineered spring flood of 2014, the delta’s birds, plants and groundwater continue to benefit, according to a report by a binational, UA-led team.
By Mari N. Jensen, UA College of Science |Oct. 19, 2016; Original Story from The University of Arizona News
Two growing seasons after the engineered spring flood of the Colorado River Delta in 2014, the delta’s birds, plants and groundwater continue to benefit, according to the latest monitoring report prepared for the International Boundary and Water Commission by a binational, University of Arizona-led team.
“This short-term event has had lasting consequences. This really demonstrates that a little bit of water does a lot of environmental good,” said Karl W. Flessa, UA professor of geosciences and co-chief scientist of the Minute 319 monitoring team.
“Some of the cottonwoods that germinated during the initial pulse flow are now more than 10 feet tall,” Flessa said.
The “Minute 319 Colorado River Limitrophe and Delta Environmental Flows Monitoring Interim Report,” released by the International Boundary and Water Commission, documents the effects of the environmental flows in the delta from the initial release of a pulse of water from March 23 through May 18, 2014, plus subsequent supplemental deliveries of water through December 2015.
Minute 319 is the 2012 addition to the 1944 U.S.-Mexico Water Treaty that authorized environmental flows of water into the Colorado River Delta from 2013 to 2017.
Birdlife responded to the post-flood burgeoning of vegetation, and bird diversity is still higher than before, the monitoring team reports. Migratory waterbirds, nesting waterbirds and nesting riparian birds all increased in abundance.
Upstream dams and water diversions for farms and cities in both countries have dried up most of the river south of the border. With the exception of a few wet years, the river has not reached the Gulf of California since 1960.
“This is the first time environmental water has ever been delivered across an international boundary.” said Eloise Kendy, a senior freshwater scientist with The Nature Conservancy’s North America Water Program.
“The level of collaboration was really unprecedented — from two national governments to the individual farmers whose irrigation canals were used for some of the water deliveries,” she said.
Flessa, Kendy and Karen Schlatter of Sonoran Institute compiled and edited the report on behalf of the binational partnership of many people and federal agencies, universities and non-governmental organizations that monitored the Colorado River Delta under Minute 319.
Some of the water from the pulse flow and subsequent smaller environmental flows recharged the groundwater, which had both ecological and social benefits, Kendy said. The vegetation greened up in areas that received surface water and also in some areas that did not.
“The farmers were happy because it recharged the aquifer they use for groundwater irrigation,” Kendy said. “And plants that were outside the inundation zone got a big drink of water.”
Before 1960, spring floods regularly roared down the Colorado River, scouring the river bottom and overtopping the bank, thereby creating the conditions necessary for cottonwood and willow trees to germinate and establish.
An invasive plant species known as salt cedar or tamarisk is now the dominant plant along the river. Cottonwoods and willows need bare ground and sunlight to germinate, so they cannot establish themselves on tamarisk-covered riverbanks, said Schlatter, a restoration ecologist of the Sonoran Institute’s Colorado River Delta Program.
The March 2014 pulse flow delivered a fraction of the water the pre-1960 spring floods delivered. People from Sonoran Institute and Pronatura Noroeste cleared some areas of non-native vegetation beforehand. The researchers hoped that reducing competition would allow native plants such as willows and cottonwoods to germinate and grow after the pulse flow.
“We mechanically cleared the tamarisk vegetation from the riverbank and old oxbows,” Schlatter said. “We reconnected the meanders to the main river channels so when the pulse flow came there were these nice backwater areas where the conditions were good for the establishment of native trees.”
Now in those restoration areas, cottonwood and willow seeds that germinated after the pulse flow have become trees 3 to 4 meters tall (10 to 13 feet), and bird diversity and abundance has increased, she said.
“Now we have diverse habitat types, including lagoons, cottonwoods-willow forest, mesquite bosque and marshes,” she said. “We are seeing a much higher diversity of riparian bird species in the restoration sites compared to other areas along the river.”
The abundance of 19 bird species of conservation concern, including vermillion flycatchers, hooded orioles and yellow-breasted chats, was 43 percent higher at the restoration sites than at other sites in the floodplain, the monitoring team found.
In addition, the pulse flow reduced soil salinity in some areas that had been targeted for restoration, Schlatter said. “We didn’t expect that — it is a huge bonus.”
Reducing the soil salinity makes conditions more favorable for native plant species.
If there’s another pulse flow, she suggests mechanically clearing tamarisk and other non-native vegetation from the river’s bank.
“We’re not going to get a huge flood on the Colorado River anymore,” Schlatter said. “If the flood isn’t going to provide the same ecological processes floods did in the past, we will have to have active management.”
Other UA members of the monitoring team are Ed Glenn of the UA Department of Soil, Water and Environmental Science and Martha Gómez Sapiens and Hector Zamora of the UA Department of Geosciences.
The International Boundary and Water Commission in El Paso, Texas, funded the UA portion of the Minute 319 monitoring program.
Carlos de la Parra of the Colegio de la Frontera Norte is co-chief scientist of the Minute 319 monitoring team. Key contributors to the report include Osvel Hinojosa of Pronatura Noroeste, Jorge Ramírez Hernández and Jesus Eliana Rodríguez Burgueño of the Universidad Autónoma de Baja California, Francisco Zamora of Sonoran Institute, Jeffrey Kennedy of the U.S. Geological Survey and Dale Turner of The Nature Conservancy.
The Minute 319 monitoring team includes more than 21 scientists from universities, government agencies and nongovernmental organizations from both Mexico and the U.S., including El Colegio de la Frontera Norte, the Ensenada-based Pronatura Noroeste, The Nature Conservancy, the Tucson-based Sonoran Institute, the Universidad Autónoma de Baja California, the University of Arizona, the U.S. Geological Survey and the U.S. Bureau of Reclamation.
Bor∙der (noun). A line separating two political or geographical areas, especially countries.
Countries, people, wildlife and even water. Edward Abbey said that there is no shortage of water in the Southwest desert but exactly the right amount, a perfect ratio of water to rock, water to sand. He said that there is no lack of water here unless you try to establish a city where no city should be.
That right amount, that perfect ratio, is nonexistent now. There used to be a river that flowed here once, but now you only see gravelly peaks, eroding sand dunes, shrubs and scattered trees holding on to the dusty soil, begging for survival.
I remember my first trip to the Delta two years ago. Watching the moon rise over Southwestern skies I was joining a group of 23 students from Whitman College on a trip to study the Colorado River Delta in Mexico. We were sitting in a circle on the sandy banks of the Colorado River Delta, surrounded by young cottonwoods and willows and munching on buffalo burgers that the cook crew just prepared.
Do you know that feeling when you are hungry and you can’t eat? When you get cranky and desperate, when even the slightest miscalculated comment from a friend can make you explode? The ecosystem here is like that. The dry desert is screaming for water and can’t get it. The touch of our hands breaks the branches, the weight of our steps causes the already cracked soil to crumble underneath our feet.
The Colorado River is one of the most controlled rivers on Earth. It starts high in the Rocky Mountains, over two miles above sea level. It is meant to meet with the Gulf of California between the Mexican states of Baja California and Sonora after flowing nearly 1,500 miles. The river does not meet the Gulf anymore. We have built more than 100 dams for flood control, hydroelectricity and storing and diverting agricultural and municipal water. These 100 dams also can act as wildlife borders and barriers.
South of the USA-Mexico border, ecosystems are weakening. The waterless riverbed echoes drought, for as far as you can see. It has been more than 50 years since the river has reached the ocean with any regularity. Countless species have disappeared from the area, migrating elsewhere and altering the ecological makeup of this place.
Guiding us through the Delta are staffers from the Sonoran Institute, one of several non-profit groups working to restore the Colorado River Delta ecosystems. These groups span national borders to restore the river in both the U.S. and Mexico. They think about the future of this tremendously important place: the birds, the fish, the rest of the wildlife and also the people here who depend on fresh water.
Following the dry channel south, we arrive where the river used to meet the ocean. We walk knee-deep in salty mud. When the tide is high it floods these plains, and years ago when the fresh river water and ocean mingled, they created a very special estuarine ecosystem. That one too, is almost gone.
More than 200 species of birds, fish, mammals, reptiles and amphibians depend on this river estuary, this fragile ecosystem: Shrimp and fish like the endangered Totoaba and desert pupfish; the Vaquita, one of the rarest ocean mammals; top-of-the-chain predators like coyotes and bobcats; at least nine species of insect-eating bats; endangered birds like the Southwestern willow flycatcher and Yuma clapper rail.
By the time the Colorado reaches Mexico, its water is distributed for agriculture, energy and drinking water. The percentage destined for the environment is nil. Three years ago, after many years of recognizing the ecological and economic importance of the Delta, the U.S. and Mexico signed an amendment to the International Boundary Water Commission 1944 treaty– called “Minute 319” in the language of treaties – to release more water south of the U.S. border and try to keep the Delta alive.
I am now part of the organization that guided me and 23 students through the Delta. The Sonoran Institute has worked here for 20 years, with efforts that follow rivers rather than borders we are now part of a growing movement of communities, governments and groups working across national lines to protect our shared ecosystems. In Tijuana, Mexico, Americans and Mexicans are combining efforts to reduce sediment, trash and polluted storm water in the Tijuana River as it flows through both nations. Joint water restoration and anti-pollution efforts are under way or planned at multiple points along the border.
On the Colorado, restoration teams decided to use Minute 319 for a grand experiment: to imitate nature with even this tiny fraction of the river’s historic flow. Mimicking the surges of snow melt that briefly fill desert river channels in the spring, they opened Morelos Dam, the last dam on the Colorado, to send a “pulse flow” of 105,000 acre-feet of water (an acre foot is the amount of water it would take to cover an acre of land at a depth of 1 foot) through the dry channels. The hope was that riverbank vegetation will be soaked and reseeded and trees will get enough of a drink to stay alive through the dry season. Over the course of eight weeks, the river ran again. For the first time in many years, the Colorado briefly met the Gulf of California.
Today, the river remains at a low “base flow” under the agreement. The river once again runs dry before it reaches the sea.
Did the pulse flow work? Can humans be clever enough, imitate nature closely enough, to bring back a habitat with just a fraction of the water it once got each year? So far we have only seen positive changes in the ecosystem, like increased seedling establishment and increased suitable habitat for native plants.
In scientific terms, success can’t be measured yet. Ultimately it will be measured by numbers, by how many wildlife species come back after being gone for decades, by how many native trees sprout, by how many meters the cottonwoods and willows grow after they are replanted.
But I like to think about measuring the success of Minute 319 and the Pulse Flow as a way of nature showing us how resilient this ecosystem can be. Saplings appeared along the river quickly after the Pulse Flow and now two years after, those trees are over 6ft tall. There are also more birds and beavers using the area, all because the presence of water and the increased connections between meanders and the main river channel. The water has also attracted the local community, giving children the opportunity to trail their hands in water where there used to be only dry channels.
Next year, 2017, the U.S. and Mexico have the chance to renew Minute 319, keeping that slender thread of the Colorado River feeding trees and shrubs, wildlife and human communities from the border to the sea. If it is approved, some day in the future perhaps the Delta will once again see the vast flocks of birds that used to stop over each winter on their journey south through the Pacific Flyway.
For now, the dry textured sand I hold in my hands speaks of memories of its underwater and borderless journey. I am holding fragments of the Rocky Mountains, I am holding pieces of the Grand Canyon. Borders won’t stop the desert dance. Life prevails.
Gabriela Gonzalez-Olimon joined the staff of the Sonoran Institute two months after this trip along the Delta. She is a biologist and works as an environmental education coordinator, taking school children to see the river make a comeback. She lives in Mexicali, Baja California.
Our restoration work in the Colorado River Delta extends beyond planting trees and the scientific monitoring of progress. Community engagement is an important part of our efforts, which includes Environmental Education Workshops throughout the year. Recently, our on-the-ground team hosted one such workshop for the Casa de la Cultura de la Juventud CREA Cultura, as part of their Summer Program (Cursos de Verano).
The children learned about “The Ecosystem of the Colorado River”, where our staff and volunteers shared information about the biodiversity that once existed in the Delta region — and what is returning with our restoration efforts. And — don’t they look as if learning this is fun?!!
Gratitude to all who helped bring together this educational program for these Mexican youth — and for all of our supporters who make this possible. These youth are the future of the Delta.
Photos byDRubio, Sonoran Institute