Denver: Watershed Summit 2019, June 27, 2019

Click here to go to the Resource Central website for all the inside skinny:

The Watershed Summit is rapidly becoming the region’s top event for water industry leaders. Join 250+ water utility executives, business leaders, conservation experts, and other professionals to gain the new insights you need to help position your organization for success.

Watershed Summit 2019 is produced through a collaborative partnership between the Colorado Water Conservation Board, Denver Water, the City of Boulder, Aurora Water, the One World One Water Center, Resource Central, and the Denver Botanic Gardens. Building on the success of the last 4 years, this one-day summit helps you get connected to industry leaders and what works best across the Mountain West.

Standard Registration: $65

We are thrilled to feature a dynamic line-up of experts in the water field who are excited to share their knowledge and join in on the conversation.

Special Guest: Phil Weiser, Attorney General for the State of Colorado

  • J. J. Ament, CEO, Metro Denver Economic Development Corporation
  • Ze’ev Barylka, Marketing Director US, Netafim
  • Cynthia S. Campbell, Water Resources Management Advisor, City of Phoenix
  • Beorn Courtney, President, Element Water
  • Lisa Darling, Executive Director, South Metro Water Supply Authority
  • Carol Ekarius, Executive Director, Coalition for the Upper South Platte
  • Jorge Figueroa, Chief Innovation Officer, Americas for Conservation
  • Brent Gardner Smith, Journalist, Aspen Times
  • Dan Gibbs, Executive Director, Colorado Department of Natural Resources
  • Kate Greenberg, Colorado Commissioner of Agriculture, State of Colorado
  • Jim Havey, Filmmaker, HaveyPro Cinema
  • Jim Lochhead, CEO/Manager, Denver Water
  • Peter Marcus, Communications Director, Terrapin Care Station
  • Fernando Nardi, Professor, Università per Stranieri di Perugia, Italy
  • Cristina Rulli, Professor, Milan Polytechnic, Italy
  • Luke Runyon, Reporter, KUNC
  • Harold Smethills, Founder, Sterling Ranch
  • Jamie Sudler, Executive Producer, H2O Radio
  • Weston Toll, Watershed Program Specialist, CO State Forest Service
  • Chris Treese, External Affairs Manager, Colorado River District
  • Larry Vickerman, Director, Denver Botanic Gardens Chatfield Farms
  • Scott Winter, Water Conservation Specialist, Colorado Springs Utility

Panel Topics Include:

  • The Colorado River
  • Water and Business
  • Agriculture
  • Watershed Health
  • Conservation and Storage

How to Cut Your Water Use in Half: These water-saving products and practices will save you money, too — Consumer Reports #EarthDay2019

Xeriscape landscape

From Consumer Reports (Mary H.J. Farrell):

California’s seven-year dry spell may be over, but there will be another drought somewhere in the country this year—and every year.

In fact, water managers in 40 states say that even under normal weather conditions, they expect water shortages in some part of their state over the next decade. That’s according to WaterSense, the water conservation partner of the Environmental Protection Agency.

There are lots of water-saving ideas floating around, but two of the best ways are to replace water-wasting appliances and fixtures and to modify your lifestyle and habits.

Neither is easy. Updating appliances requires an up-front expense, and creating new habits a long-term commitment. But do both and you can cut your usage in half or more. That’s as good for your budget as it is for Earth.

Outdoor watering accounts for almost 30 percent of your water use, according to WaterSense. And toilets (24 percent), showers (20 percent), faucets (19 percent) and washing machines (17 percent) also use substantial amounts. Then there’s the 12 percent of water lost to leaks that you might not even know about. (To find and detect leaks, read “Is Your Toilet Running Up Your Water Bill?”)

Here are some ways to save water and reduce your water bill from the experts at Consumer Reports, Energy Star, and WaterSense. We’ll take you room-by-room and then outside.

Save Water in the Bathroom
More water flows through the bathroom than any other room in the house. In fact, bathrooms account for more than half of all indoor water use.

But advances in plumbing technology mean that newer faucets, showers, and toilets use significantly less water than older models and still deliver the rinse, spray, and flush you expect.

Water-saving bathroom fixtures that meet federal WaterSense standards carry the WaterSense label. Here are the water-saving steps you can take:

Replace your old toilets—all of them. Older toilets use as much as 6 gallons per flush; new WaterSense toilets do the job with 1.28 gallons or less. With new toilets, the average family can reduce water use by 20 percent per toilet.

Take short showers, limiting them to 5 minutes. (And take showers instead of baths.) If you’re brave, turn off the water when lathering up or shampooing. And shut off the water when brushing your teeth or shaving.

Replace your old showerhead. Standard showerheads use 2.5 gallons of water per minute. WaterSense showerheads use no more than 2 gpm. The difference really adds up.

Replace your old faucets. Replacing leaky or inefficient faucets and aerators with WaterSense models can save the average family 500 gallons of water per year.

Don’t use your toilet as a garbage can. It wastes water and can clog your pipes. Toilet paper is designed to disintegrate. Tissues, most wipes, and dental floss are not.

Save Water in the Kitchen
When it comes to wasting water in the kitchen, the dishwasher isn’t the culprit—it’s probably you.

Too many people rinse their dishes clean before putting them in a dishwasher designed to do that very job—and do it better than you can. Here are the water-saving steps you can take:

Don’t prerinse your dishes. An old kitchen faucet can use 7 gallons of water a minute when running full blast.

“The Energy Star dishwashers we test use 4 to 6 gallons per cycle,” says Larry Ciufo who oversees Consumer Reports’ dishwasher tests. Water savings aside, your dishwasher will perform better loaded with dirty dishes, as CR explains in “Don’t Bother Prerinsing Your Dishes.”)

Replace your old dishwasher. Energy Star dishwashers are about 15 percent more water-efficient than standard models. Bonus: They’re quieter, too.

Wash only full loads of dishes. For maximum efficiency, load your dishwasher according to the instructions in your owner’s manual, which will make the most of the sprays in your machine.

Refrigerate your drinking water instead of running the tap until it’s cool. Designate one glass or water bottle per person for the day so that it only needs to be washed once.

Give pots and pans a soak instead of scrubbing them under running water.

Install a WaterSense aerator on the kitchen faucet to reduce flow to less than 1 gallon per minute. It’s a cheap fix that costs only pennies. Avoid running the garbage disposal, and the water it requires, by composting your food scraps.

Save Water in the Laundry Room
The worst washing machines in our tests use more than twice as much as miserly Energy Star models, which use 10 to 12 gallons for an 8-pound load. Front-loaders are the most water efficient, followed by high-efficiency (HE) top-loaders and agitator top-loaders.

Here are the water-saving steps you can take:

Replace your old washer. Energy Star washing machines use about 40 percent less water than a regular washer. Bonus: Because high-efficiency models spin faster, the clothes need less drying time.

Pick the appropriate water level setting—often called small, medium, large—for the load if that’s how your machine works. Front-loaders and most HE top-loaders have auto-load sensing, and a few of the latest agitator top-loaders have it, too. That feature automatically determines the load size and the amount of water needed.

Measure laundry detergent and use HE detergents for HE machines. Regular detergents are too sudsy, and using too much can cause HE washers to use more water by extending the rinse cycle.

Do only full loads, but don’t overstuff. Using cold water whenever possible helps save on energy costs.

Pick the right soil setting for the load. Choosing the heavy-duty setting can use more water and extend wash time. The normal setting works for most loads.

Save Water Outdoors
Lawns soak up more water than any other plant in your yard, and homeowners tend to overwater their grass to keep it green.

An established lawn needs only 1 inch of water per week in the growing season, so pouring on the water can actually harm your turf, as well as your budget.

Here are the water-saving steps you can take:

Let the grass grow longer by raising your lawn mower’s cutting height. Longer blades of grass help shade each other, reducing evaporation, so keep your grass between 3 and 4½ inches tall.

Stop fertilizing; it only promotes new growth. When you mow, leave grass clippings on the lawn to retain moisture and add nitrogen. If you use a sprinkler, direct the spray to the grass and garden and not the sidewalk and street.

Don’t use water to clean off your driveway, steps, or deck. Sweep them instead or use a leaf blower. Wash your car with water from a bucket or go to a commercial car wash that recycles water.

When it rains, collect the water in barrels or install gutters and downspouts that direct the runoff to your plants and trees.

Reduce the size of your lawn. Consider replacing grass with mulch, ground cover, drought-tolerant plants, or ornamental grasses. Weeds compete with other plants for water, so weed regularly. And ditch any water features unless they use recycled water. To find the best plants for your region, consult your county cooperative extension or a local nursery.

Use soaker hoses or drip irrigation, if watering is permitted, to apply water slowly and evenly. Buy a hose nozzle with an automatic shutoff. Water early in the day when evaporation rates are low and more water is absorbed.

2019 #COleg: Governor Polis signs HB19-1200 (Reclaimed Domestic Wastewater Point Of Compliance)

Graywater system schematic.

Click here to go to the Colorado Legislature website to read the bill:

Concerning the point of compliance related to the treatment process involved in treating reclaimed domestic wastewater for indoor nonpotable uses within a building where the general public can access plumbing fixtures that are used to deliver the reclaimed domestic wastewater.

SESSION: 2019 Regular Session
SUBJECTS: Natural Resources & Environment Water

BILL SUMMARY
In 2018, the general assembly authorized the use of reclaimed domestic wastewater for irrigation of food crops and industrial hemp and for toilet flushing if, at the point of compliance in the water treatment process, the reclaimed domestic wastewater met certain water quality standards.

The bill authorizes the water quality control commission (commission) to adopt rules requiring a point of compliance for disinfection residual related to the treatment process for reclaimed domestic wastewater used for toilet flushing within a building where the general public can access the plumbing fixtures used to deliver the reclaimed domestic wastewater. If the commission adopts the rules, the rules must establish a point of compliance for disinfection residual at a single location between where reclaimed domestic wastewater is delivered to the occupied premises and before the water is distributed for use in the occupied premises.

Colorado NRCS now accepting applications for 2019 Agricultural Land Easement and Wetlands Reserve Programs — High Plains/Midwest Ag Journal

Irrigation sprinklers run over a farm in Longmont in the South Platte River basin. Photo credit: Lindsay Fendt/Aspen Journalism

From The High Plains/Midwest Ag Journal:

Clint Evans, Colorado State conservationist for USDA’s Natural Resources Conservation Service recently announced applications for the 2019 Agricultural Conservation Easement Program—Agricultural Land Easement and Agricultural Conservation Easement Program-Wetlands Reserve Program—are currently being accepted on a rolling basis. Due to the new 2018 Farm Bill, Colorado NRCS will not be announcing an application deadline for either program at this time. A subsequent announcement will be made at least 30 days prior to any established deadline in 2019.

The purpose of the ACEP-ALE program is to protect the agricultural viability, grazing uses and related conservation values by limiting nonagricultural uses of the land. The purpose of the ACEP-WRE program is to protect and restore wetlands, wildlife habitat, and water quality on agricultural lands. These programs are voluntary and the landowner retains ownership of the land.

Applicants for ACEP-ALE must be a federally recognized Indian Tribe, state or local units of government, or a non-governmental organization. Individual landowners may apply for ACEP-WRE if their land includes farmed or converted wetlands that can be successfully restored or other eligible wetland type.

Completed application packets for ACEP-ALE should be emailed to Heather Foley at heather.foley@co.usda.gov or mailed to Heather Foley, easements coordinator, USDA-NRCS, Denver Federal Center, Building 56, Room 2604, Denver, CO 80225. Completed application packets for ACEP-WRE must be submitted to the local NRCS field offices located within USDA Service Centers. Application packets for either program must be submitted based on the 2018 guidelines.

For more information about NRCS easement programs, please contact Heather Foley at 720-544-2805 or heather.foley@co.usda.gov. You can also visit your local NRCS Service Center or visit the Colorado NRCS website at http://www.co.nrcs.usda.gov.

Resisting the Lure of the Lawn — The Walton Family Foundation #ActOnClimate

From The Walton Family Foundation (Jill Ozarski):

In Colorado, water-conscious homeowners are protecting river health by removing thirsty turf landscapes

For millions of homeowners, the romantic lure of the lawn is impossible to resist.

Americans are said to have a “love affair with lawns,” spending billions of dollars each year to cultivate and care for vast expanses of lush green grass in front and back yards across the country.

Rachel Mondragon doesn’t understand the appeal.

Over the past four years, the suburban Denver resident has been steadily removing turf grass from her property in the foothills of Colorado’s front range.

Not only does a ‘perfect lawn’ hold little aesthetic value for Rachel, she is bothered by the environmental costs of keeping the grass growing in a semi-arid region under persistent threat of water shortages.

“I kept thinking, ‘Why are we spending so much time, water and effort on this grass turf when, honestly, it just doesn’t bring any joy to my life,” Rachel says.

“I want to save on water. The idea of needing to water the lawn every day, and the thought of all that water going just to grow grass that’s not even native to this area, it just didn’t make sense to me.”

Rachel’s desire to remove her thirsty lawn led to her participation this year in a pilot project designed to help Colorado residents to make the shift from turf to a more water-efficient landscape.

The program, run by the Boulder-based non-profit Resource Central, offered a menu of incentives to 60 homeowners interested in converting their lawns into xeriscape gardens that feature low-water plants, mulches and other turf options that reduce or eliminate the need for supplemental irrigation.

Video: Ranching in the New Normal: Adapting to Drier Future — @AmericanRivers @AudubonRockies #RioGrande #ColoradoRiver #COriver #aridification

Green River Ranch. Photo credit: Abby Burk

From Audubon Rockies:

After 19 years of drought in the Colorado River basin, many experts are calling this prolonged drying out of the southwest by a new name: aridification. Drought implies there’s an end, but what if there’s not? Right now people across Colorado and the Colorado River basin are working together to find water solutions to save the Colorado River and the livelihoods of those who depend on it.

The land and water support us now, but belong to the next generation of people and wildlife. The people who understand this most work Colorado’s land and water every day. Working land operations—like ranchers—survive by how they relate to land and water. These operations, in turn, provide vast open space for birds, other wildlife, and our enjoyment.

The dry year of 2018 pushed working lands and rivers to the brink across Colorado and the Colorado River basin. Many Colorado ranching families, communities, and wildlife that rely on healthy flowing rivers were stretched thin as some rivers completely dried up.

Take a look at our thoughtful new film: Ranching In The New Normal, a collaborative project between Audubon Rockies and American Rivers. This film takes a peek into three Colorado ranches as they adapt to increasingly dry conditions and the hope they have for their land and water legacy.

Help us keep rural agriculture and hardworking rivers thriving. Join Audubon’s Western Rivers Action Network to help protect our rivers, working lands and wide open landscapes that birds and people need.

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.”