Colorado College's 2012 State of the Rockies Report

Youth and the Colorado River Basin:
Perspectives and a Call to Action

By: Walter E. Hecox Ph.D., faculty director;

Brendan Boepple, program coordinator;

and Debbie Kelley, Project Writer
2012 Colorado College State of the Rockies Report Card
for Mountain West News

April 24, 2012

The entire report is posted on the State of the Rockies Project website: http://www2.coloradocollege.edu/stateoftherockies.

The Environment Needs To Have a Voice

In this year’s annual report, student researchers studied a number of issues surrounding the Colorado River Basin, including the environment, ecology and climate. In the environment and ecology section, senior Natalie Triedman identifies four key findings:

• Human needs have historically taken precedence over environmental concerns when managing Colorado River water and other natural resources.
  
  
• The diversity of local habitats and the demand for unique management approaches complicates how we manage environmental concerns on the Colorado.
  
  
• The riparian zone (which lies adjacent to the river) is deteriorating, which is negatively impacting native plant and animal species that rely on this unique habitat.
  
  
• To this day, no specific water quantity on the main stem of the Colorado River is designated for environmental needs. The threat of endangered species and degraded water quality are both amplified by the fact that we do not allocate a significant quantity of water exclusively for environmental needs.

It's easy to overlook the environmental threats, Triedman believes, considering the ecological beauty throughout the seven-state Colorado River Basin, which includes some spectacular natural wonders ranging from the Rocky Mountain National Park to the Grand Canyon.

People who live in or visit the region may be deceived by the array of colorful flora and impressive wildlife, potentially obscuring environmental threats not apparent to the casual observer.

Not only are a number of species at-risk rising and the natural habitat becoming degraded, but the quality of water is also threatened by salinity, sediment and metals.

To reach her conclusions, Triedman looked at several factors, including key indicators of a river system’s health: biodiversity, water quality and water quantity.

The 242,000 square miles of the Colorado River extend across many different eco-regions with distinct environmental profiles. Diverse geography ranges from the snow-capped Rocky Mountains to the dry delta in Mexico, where the river no longer reaches the sea, due to dams, diversions and water depletion.

Despite the variation in climate, hydrology and ecology, these diverse habitats are united by the fact that they all rely on a healthy riparian environment -- the transition zone between land and river.

Plants and animals in the Colorado River Basin are dependent on this resource-rich buffer zone, which is becoming increasingly threatened by dams and diversions, invasive species, pollution and water depletion.

From the bears, elk, bighorn sheep, marmots and pika that inhabit Rocky Mountain National Park, to the Grand Canyon National Park, home to seven different life zones with over 1,500 species of plants, 355 species of birds and 89 species of mammals, the river is a vital life source.

But endangered species abound, and the number of reptiles, amphibians, birds, fish and mammals on the list continues to grow. Triedman looks in-depth at four endangered fish in the Colorado River: The bonytail chub, the Colorado pikeminnow, the humpback chub and the razorback sucker.

Invasive species also exacerbate the threat of extinction endangered plants and animals by acting as competitors and predators to the native species. Invasive species are nonnative organisms that have been introduced, either intentionally or unintentionally, to a new geographic location that has conditions that foster its proliferation.

In a case study, Triedman examined the invasive tamarisk shrub, more commonly known as the salt-cedar, the environmental impact it's having, aerial spraying efforts to curb growth, and the controversial introduction of the tamarisk leaf beetle as a control method and restoration efforts.

In another case study, Triedman presents detailed information about two invasive mussels, the zebra and quagga.

She calls for political and public recognition that diversions on the Colorado River, to serve social and economic needs, have come at the expense of stream flows, which has had devastating consequences on the water quality and native ecology of the river.

"It is time that we test the flexibility of western water law. The current legal structure, based on prior appropriation and a limited hierarch of "beneficial uses," is outdated and requires reform," she writes. "Economic and ecological threats to the Colorado River Basin urge us to improve the water acquisition and use processes so that water remains for nature under constructs that make instream flow rights legally defensible in all Basin states."

Changing Climate a Cause for Concern

The changing climate also has had a significant impact on the river hydrology. Temperatures have been steadily increasing in the western United States since the 1970s, and the Colorado River Basin has experienced more warming than any other region in the country.

Increasing mean annual temperatures have caused a shift in the timing of peak annual runoff so that high flows are consistently occurring earlier in the year.

Another manifestation of warming temperatures has been increased evaporation from snowpack, which has resulted in less runoff overall.

Plants and animals are dependent on the specific hydrologic patterns typical of the Colorado River for habitat, migratory patterns, food distribution, and development and growth. Species are currently faced with the challenge of adapting to new flow patterns in a short period of time.

In another section of the 2012 State of the Rockies Report Card, Colorado College student researcher Carson McMurray studied whether climate change is creating a “perfect storm” for the Colorado River Basin in the 21st century.

The short answer: Yes.

McMurray’s key findings:

• The effects of climate change are already being felt within the Colorado River Basin.
  
  
• Over the next century, flows of the river are predicted to decrease by 6 percent to 20 percent.
  
  
• Releases of water to the Lower Basin will meet Compact obligations less than 70 percent of the time.
  
  
• Adaptation will require an adaptive management plan to adjust for new data and technology.

As climate change effects begin to surface after years of unsustainable greenhouse gas emissions, the southwestern United States, specifically its hydrology, will be drastically affected, McMurray concludes.

In a review of 19 global climate models by the Intergovernmental Panel on Climate Change (IPCC), the group noted "there is a broad consensus amongst climate models that this region will dry significantly in the 21st century and that the transition to a more arid climate should already be underway"

The Bureau of Reclamation has also found consensus among federal climate models that predict a significant decrease in water availability by the end of the 21st century.

Lower precipitation, higher temperatures and other factors are expected to create basin-wide drought conditions. The Palmer Drought Severity Index (PDSI), created by Walter Palmer in the 1960s, determines dryness using temperature and precipitation data. Between the years 2035 and 2060, the Upper Basin’s moisture balance is predicted to be similar to the worst drought on record.

Future scenarios indicate it will be difficult for the Colorado River Basin to meet its legal requirements for water allocations. In preparation for what's to come, McMurray offers several recommendations, including underground storage of water and artificially replenishing aquifers, using controversial new sources of water, such as cloud seeding, and desalination of brackish water.

 

 

This is the first of a three-part series on Colorado College’s 2012 State of the Rockies Report Card on the Colorado River Basin.

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By: Walter E. Hecox Ph.D., faculty director;
Brendan Boepple, program coordinator;
and Debbie Kelley, Project Writer

2012 Colorado College State of the Rockies Report Card
for Mountain West News

Colorado College’s 2012 State of the Rockies Report Card is dedicated to a single topic of vital interest: the past development, present condition, and future options for the Colorado River Basin. We add a special dimension: the perspectives of today’s youth who will become tomorrow’s Basin users and stewards.

Competing interests for water rights and a dwindling supply of the vital natural resource have created challenges for the Colorado River Basin, which stretches across portions of seven Southwestern states. Some experts predict that by 2050, climate change and burgeoning uses of the river system will result in inadequate water to meet all of the shares allocated for municipal, agricultural, industrial and wildlife use, two-thirds to nine-tenths of the time.

But such a crisis can be averted, if actions are taken now, according to findings from this year’s State of the Rockies Project.

Conducted by students and faculty at The Colorado College in Colorado Springs, each year a research project is undertaken to increase public understanding of issues affecting the environment and economy of the Rocky Mountain region.

This year’s topic of study: The Colorado River Basin. Student researchers spent last summer and the 2011-2012 academic year analyzing the 1,400-mile waterway, wrote sections of the Report Card on critical dimensions, and recommended five action steps so that a viable, living Colorado River Basin exists, even thrives for the next generation. Their work was unveiled and the Report made public during the April 9-10 State of the Rockies Project Conference.

Held at Colorado College, the conference not only unveiled the report but also featured as guest speakers U.S. Secretary of the Interior Ken Salazar, who discussed the challenges of saving the river basin now and in the future. And Colorado Gov. John Hickenlooper addressed what future generations can do to manage the state’s water resources.

The entire 2012 State of the Rockies Report Card is posted on the project website: http://www2.coloradocollege.edu/stateoftherockies

Here is a summary of the project team’s overview of the basin.

A Crucial Link

The Colorado River is often referred to as the lifeblood of the American Southwest. The river begins both as snowmelt at its headwaters in mountainous northern Colorado, and as the origin of the Green River in the Wind River Range of Wyoming; then winds through seven states and approximately 1,400 miles of stunningly diverse ecosystems before it reaches its delta and the Gulf of California in Mexico.

Thirty million Southwesterners, 20 Native American tribes, and Northern Mexico, as well as numerous species of flora and fauna, rely on its waters for their livelihoods and day-to-day survival. The river supports major cities such as Denver, Los Angeles, Phoenix and Las Vegas, through a carefully regulated dam, canal and pipeline system.

However, municipal uses pale in comparison to the nearly three million acres of farmland that utilize close to 80 percent of the river’s annual flow. Yet the flow is not what it once was, as drought, over-apportionment, and ever-expanding urban development have depleted the supplies of this cherished resource to the point where it no longer reaches the Gulf of California.

Its future has become increasingly contentious and uncertain.

Laws and Apportionment

The Colorado River Basin is ruled by a compilation of decrees, rights, court decisions and laws that together are referred to as the “Law of the River.” The keystone of these “commandments” is the 1922 Colorado River Compact, an interstate agreement created by the seven basin states with provisions for general water allotments, including a 7.5 million acre feet (maf) annual delivery requirement from the Upper to the Lower Basin.

Major tributaries of the Upper Basin include the Green, San Juan, Escalante, Gunnison and Dolores Rivers. The Lower Basin is fed largely by the Paria, Virgin, Little Colorado, Bill Williams and Gila Rivers.

The basin, its water apportionment, and the protection of its environmental resources have long formed a complex combination of states’ rights, federal agency involvement and Native American tribal water rights, and as such, has often been a ground for both conflict and cooperation.

The 1928 Boulder Canyon Project Act (along with the 1963 Supreme Court decision in Arizona v. California) divided the Lower Basin’s 7.5 maf between Arizona, California and Nevada.

The 1948 Upper Colorado River Basin Compact divided the Upper Basin’s average allotment of 7.5 maf among the five states.

States allocate their individual shares of river waters and, ultimately, have the highest authority after the Secretary of the Interior, who has the final ruling on nearly every conflict, from the definition of "beneficial use" to the creation of shortage guidelines.

Since 2000, the Colorado River Basin has been in a period of drought, marked by decreased precipitation and increased average temperatures. Also, constant development and manipulation of the Colorado River threaten the quality and quantity of the water supply.

The demand for water has historically been greater in the Lower Basin, home to larger cities and agricultural operations with a more arid climate. As a result, prior to 2000 the Lower Basin was using more than its allotted 7.5 maf. In the past, the Upper Basin has under-used its allocation, partly for lack of adequate storage capacity and partly because it is less populous.

Overall, water use throughout the entire basin has been slowly overtaking supplies of the river, causing concern about over-allocation of future flows.

Some of the Issues

Forty-five percent of Colorado River water is diverted out of the basin for agricultural, municipal and industrial use; many cities such as Denver, Los Angeles, and Salt Lake City already rely heavily on transbasin diversions which disrupt surrounding ecosystems.

Contamination from agricultural and urban run-off, toxic leaching from mines, and the disruption of nutrient and sediment flow caused by dams are just a few examples of how current use and manipulation of the Colorado River can threaten ecosystems along the river through the deterioration of water quality.

Sediment is another concern. Historically, the flow of sediment facilitated construction of natural sandbars that served as the foundation for a diverse makeup of fish and wildlife. Many species evolved so that they could thrive in the sediment-rich environment of the free-flowing river, a condition that no longer exists, as the construction of dams in the Colorado River Basin has disrupted the natural flow of sediment downstream.

Dams cause sediment to build up in the reservoirs, thus also decreasing the storage capacity and making the dam system less efficient for water storage and electricity generation.

Today’s high salinity levels are threatening agricultural, municipal and industrial users, as well as the river's fish and wildlife populations.

In 1974, the Colorado River Basin Salinity Control Act was passed in an effort to control the salinity of the water being delivered to the Lower Basin and Mexico.

Between $306 and $312 million are spent each year on salinity control. The Bureau of Reclamation estimates that by 2025, the number will increase to $471 million annually, if no additional projects are put in place.

The natural environment of the basin is struggling; 5 percent of the Colorado River’s native fauna are already extinct and 32 percent are currently endangered. Of the 14 native fish in the Colorado River, four species are currently endangered. They are threatened by stream flow regulation, habitat modification, poor water quality and competition with nonnative species.

The climate of the Colorado River Basin also is a serious consideration for the future, with average temperatures predicted to increase, and precipitation and runoff expected to decrease.

If efforts are not made to reach a careful balance between supply, demand and competing uses, the negative impacts will become amplified and lead to drastic changes in the state of the Colorado River.

While most matters of the river are currently in the hands of powerful stakeholders and politicians, what happens in the next decade largely dictates the future of the river for the next generation and beyond.

It is time for the younger generation to become informed, involved and engaged in making clear its desires, expectations and solutions for the future of the Colorado River, before it is too late.