The Uncertain Future of the Colorado

In this final post, the uncertain future of the Colorado River will be addressed. I will begin by looking at a national level attempt to prioritize water, followed by why the future is so uncertain for the Colorado River.  

 

Photo courtesy of ecology110fra.files.wordpress.com

“The Colorado River is at a critical crossroads, depleted by an ongoing dry cycle not recorded since more than a century ago and entangled with the future of a growing Western region.” As discussed in previous posts, there are many challenges in managing the Colorado River Basin and solutions will only be found through cooperation of all parties involved.

American Clean Energy Agenda

This past July, it was revealed to members of the U.S. Senate Committee on Energy and Natural Resources that the findings of the Bureau of Reclamation Supply and Demand study of the Colorado River projects a shortfall of 3.2 million acre-feet of water by 2060.

Photo courtesy of www.americancleanenergyagenda.org

In order to help alleviate some of the water stress in the basin, the American Clean Energy Agenda, an executive order, was presented to the President. This order aims to,

• Make water a national priority
• Create a national water census
• Formation of a water budget commission
• Reduction or elimination by 2030 of water-dependent power generation sources such as coal-fired or nuclear power plants.

Uncertain Future

One of the biggest issues surrounding the uncertain future of the Colorado River is the effect of climate change. It is no secret that the effects are already being seen along the river. Out of the last 13 years, 10 have been the lowest flow years in more than a century of record keeping. Increasing temperatures in the basin have led to greater evaporation within many of the reservoirs as well as reducing the amount of snowpack received in the headwater regions of the basin.

Colorado River supply versus demand
Photo courtesy of www.nature.org

The next major uncertainty affecting the future of the basin is in regards to the growing populations in the Southwest. Today, Southwestern United States is one of the fastest growing regions in the U.S.  With more people moving to the Colorado River Basin region, there will be an increased demand for Colorado River water on all fronts.

Finally, structurally speaking, reservoir levels along the Colorado River have been at record lows over the last decade placing many of the hydropower turbines at risk of damage. Lake Mead, which sits on the border between Nevada and Arizona behind Hoover Dam, is expected to drop 2.4 meters in 2014, as less and less water flows downstream from Lake Powell. This drop is in part due to the U.S. Bureau of Reclamation's need to cut Lake Powell’s water release by nearly 1 billion cubic meters to 9.2 billion cubic meters for the 2014 water season, the smallest release since the lake was filled in the 1960s. 

To give an idea of how much water that is, imagine an Olympic sized swimming pool 2,500,000 liters of water so 1 billion cubic meters of water would be about 400,000 Olympic sized swimming pools. 

Photos courtesy of slideshare.net/cheatles/where-is-all-the-water

Worst case scenario, when the water level drops below 1063 meters in Lake Powell, just about 30 meters lower than its average August levels, vortex action would draw air into the turbines and damage them. What is actually occurring though is a decline in power output as water levels within the reservoirs fall. This becomes problematic because “if electricity has to come from somewhere else, delivering drinking water to some of the largest cities in the western United States could be challenging. Nearly 30 percent of the energy from Hoover Dam goes to the Metropolitan Water District of Southern California, which provides drinking water to nearly 19 million people across 26 cities and water districts. Less power also means less money for various water quality and environmental studies that inform how the water from the Colorado River should be allocated.” 

Glen Canyon Dam in front of Lake Powell
Photo courtesy of cache2.artprintimages.com

Due to the complexity of the situation and the many issues and stakeholders involved, in order to secure a viable future for the Colorado River will be through multiple solutions and cooperation between all seven basin states. Unfortunately, these collaborative efforts are not easy when discussing this vital natural resource that so many people depend on and thus, tensions will increase, leading to greater problems. Nevertheless, because the Colorado River is listed as the most endangered river in the world, efforts are being made to ensure its revival. 

Dried Up Delta

In this post, I will explore issues surrounding the Colorado River Delta, noting why the delta is of importance, and how today these issues are being addressed in order to ensure a sustainable future for the ecosystems involved.

Dried up Colorado River Delta
Photo courtesy of davidmfrey.com

Before the development of the Colorado River, the river wound its way, untamed to the Gulf of California in Mexico.  The Colorado River Delta once extended over most of the Salton Trough, pictured below, but due to the high demand of the river’s water, today the delta has been depleted. 

Salton Trough
Photo courtesy of wikipedia.org

A Look Into the Delta’s Past and Current State

The Colorado River Delta was once a thriving and dynamic environmental system home to freshwater, brackish, and saltwater species.  This unique combination of habitats was due to the interaction between the ocean’s tide and the Colorado River’s flows. The historic delta was comprised of over 2.5 million acres of wetlands and provided habitat for an estimated 400 species of plants and wildlife. Once the river reached the delta, it broke off into multiple small channels covering the entire Salton Trough, creating an extensive wetland. Below is a picture of what the Colorado River Delta once looked like when the Colorado River waters reached the Gulf of California.  

 

Healthy Colorado River Delta
Photo courtesy of www.geo.arizona.edu

At one point in time, before the construction of various dams along the river, significant quantities of nutrient-rich silt were carried down the Colorado River to the delta.  Today, with the exception of a few unusually wet years, the Colorado River Delta looks like a barren desert.  Pictured below is an image of the delta taken on September 8, 2000 by the Spaceborne Thermal Emission and Reflection Radiometer flying aboard the Terra spacecraft.

Photo courtesy of earthobservatory.nasa.gov

In this image, the Colorado River is the dark blue line at the top left and weaves its way through the multicolored farmlands in the northwestern corner, finally reaching its end at the base of the Sierra de Juarez Mountains.  It is clearly noticeable in this image that a good amount of the Colorado River water is pulled out for irrigation of farmlands. “Roughly 10 percent of all the water that flows into the Colorado River makes it into Mexico and most of that water is used by the Mexican people for farming.” 

“The bluish purple river that appears to be flowing from the Gulf of California to the north is actually an inlet that formed in the bed of the Colorado River after it receded.” All of the gray areas surrounding the inlet are mud flats created over the last millions of years, before the construction of dams, by sediment carried down from the river. Lastly, the yellow expanse to the east of the farmlands is the Gran Desirto and the bluish-green patch located between the farmlands and the desert is known as the Sienega de Santa Clara. The Sienega de Santa Clara is a salt-water marsh home to many bird populations, including the endangered species, Yuma Clapper Rail and the Southwestern Willow Flycatcher. 

Below, two images of this region are pictured showing the great recession of the Colorado River Delta over time. The image on the left, from 1985, shows flows from a relatively wet year while the image on the right, from 2007, shows the current state of the delta with limited flows to this region.

Two photos of the Colorado River Delta. Left image taken in 1985 in a record high flow year while the image on the right, taken in 2007 was in a record low flow year.
Photo courtesy of coastalcare.org

Delta Recovery Efforts

The recovery of the Colorado River delta is of great importance in sustaining the future of the river and thus, many new efforts to improve the delta’s condition have been made.  In particular, Minute 319, a landmark agreement made between the U.S. and Mexico that “defines how the two countries will share Colorado River water amidst growing pressures on water resources” was passed. The key features of Minute 319 are the environmental component to bring water back to the Colorado River in Mexico and to expand restoration efforts in the delta.

Photo courtesy of www.sonoraninstitute.org

Prior to the agreement of Minute 319, the Colorado River Delta Water Trust was created in order to “acquire and lease water for environmental purposes.” Once Minute 319 was passed, the Colorado River Delta Water Trust was to “secure one-third of the total flows that will be allocated to the Colorado River, while Mexico and the U.S. will contribute the remaining two-thirds of the flows.” In regards to expanding the restoration efforts, the agreement requires the NGO coalition to widen restoration efforts in the Delta.

Currently this coalition is partnering with the Nature Conservancy, National Fish and Wildlife Foundation, and the Redford Center along with various governmental organizations in a project called “Raise the River.” The goals of Raise the River are to,

• Secure a base flow for the river
• Temporarily reconnect the Colorado River with the sea
• Enhance 2,300 acres of habitat by 2017

By accomplishing these goals, Raise the River will establish a framework for the long-term dedication of water to the Colorado River Delta.

In my next and final post, I will discuss the outlook on the future of the Colorado River. With much uncertainty surrounding this issue, there is one thing that is for certain, something must be done to protect the Colorado River from drying up if it is to continue flowing for the centuries to come.  

Four "Big-River" Endangered Fishes

This post will explore a series of endangered species that reside along the Colorado River. I will investigate four fish species in particular, the Colorado pikeminnow, razorback sucker, humpback chub, and the bonytail chub, all of which are federally endangered.

Due to both the climatology of the Southwest and the increasing demands for Colorado River water for human purposes, many species have suffered the consequences.  Historically, the Colorado River Basin was home to 30 species found no where else.  Today, four of these 30 species are extinct and 16 are listed as threatened or endangered under the Endangered Species Act.

Photo courtesy of lh4.googleusercontent.com

A Brief Synopsis of the Endangered Species Act

According to the Endangered Species Act (ESA), a species listed as “endangered” means a species is in danger of extinction throughout all or a significant portion of its range. “Threatened” means a species is likely to become endangered within the foreseeable future. Once a species is listed, both the species and their habitat is protected by prohibiting the “taking” of listed species. “Taking” is defined by the ESA as “to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect or attempt to engage in any such conduct.” Prohibited actions may also include “significant habitat modification of degradation where it actually kills or injures wildlife by significantly impairing essential behavioral patterns, including breeding, feeding, or sheltering.”

Four “Big-River” Fishes

Photo courtesy of www.mountainijournals.com

Four fish species along the Colorado River who are currently listed as endangered by the ESA are the Colorado pikeminnow, razorback sucker, humpback chub, and the bonytail chub.  These four fishes are unique in that they are only found in the Colorado River Basin.  All four are large, long-lived, warm-water species that are thought to have evolved three to five million years ago.

Colorado Pikeminnow
Photo courtesy of http://www.natgeocreative.com

Colorado Pikeminnow

The Colorado pikeminnow is noted for being the largest species in the minnow family in North America. Records show individuals of this species growing to a length of 6 feet long and weighing over 100 pounds.  Today, the Colorado pike minnow generally grows to a length of two and a half feet weighing between 5 and ten pounds.

Razorback Sucker

Razorback sucker
Photo courtesy of dnr.state.co.us

The razorback sucker is another big fish characterized by its sharp, bony, “razorback” hump. This species can grow up to lengths of three and a half feet and weigh up to 15 pounds.  This species once thrived throughout most of the medium and large sized rivers of the Colorado River Basin, but its range has dwindled to only the Colorado River above the Grand Canyon, and various big lakes on the lower Colorado River.

Humpback Chub

Humpback Chub
Photo courtesy of mediad.publicbroadcasting.net

Humpback chub are distinguished by the abrupt, fleshy hump behind their head. This species can grow to lengths of three and a half feet and has a body that is almost entirely scaleless.  This fish thrives is deep, swift-water habitats and usually is found in smaller populations. Historically, the humpback chub ranged on the Colorado River from below present-day Hoover Dam upstream into Colorado, aswell as in portions of many of the Colorado River tributaries in Arizona, Utah, Colorado, and Wyoming.  Today, there are only seven population centers of the humpback chub.

The location of the humpback chub population centers in the Colorado River Basin.
Photo courtesy of www.utexas.edu

Bonytail Chub

Bonytail Chub
Photo courtesy of www.coloradoriverrecovery.org

The bonytail chub is the rarest of the four fish species discussed.  This species can grow to over two feet long.  Once found in a number of states, including Arizona, California, New Mexico, Utah, and Wyoming, this fish species has since experienced the most abrupt decline of any of the long-lived fishes native to the main-stems of the Colorado River system and, because no young individuals have been found in recent years, has been called functionally extinct.

Reason for the Decline in “Big-River” Fishes

Hoover Dam
Photo courtesy of 4.bp.blogspot.com

The reasons for becoming listed vary for each of the four species but collectively, the construction and management of dams and diversions has effected these populations the most.  The combination of regulated flows, decrease in sedimentation and change in pH levels downstream due to dams has degraded the ecosystems and habitats of the “big-river” fishes.  For the humpback chub, a threat to its species has been competitive non-native predators as well as the spread of parasites and diseases.  Lastly, with the increase in demand for Colorado River water, a conflict between consumers and the ESA arose over the appropriate use of water.

Recovery Programs and Their Effectiveness

Currently, there are two main recovery programs that the U.S. Fish and Wildlife Service is working on along side with other state and federal agencies, water and power organizations, and tribes in order to recover the four “big-river” fish species. The first program is the Upper Colorado River Endangered Fish Recovery Program established in 1988, which includes the Colorado River upstream of Glen Canyon dam.  The second project is the San Juan River Basin Recovery Implementation Program created in 1992, which includes the entire San Juan River, a significant tributary of the Colorado River.

Photo courtesy of image.slidesharecdn.com

There are a number of key elements within these two programs to aid in recovering the four fish species. Below are a few of the main areas of emphasis.

• Improving river flows and habitats through modification of dam operations and cooperative agreements to enhance flows
• Construction of five fish passages around dams and diversions to link more then 375 river miles of designated critical habitat
• Instillation of fish screens to prevent fish from getting caught in irrigation canals
• Restoration of 3,000 acres of floodplain habitat
• Raising endangered fish in hatcheries and stocking them to reestablish naturally self-sustaining populations

It is important to note that these projects would not be possible without the cooperation of multiple parties working to recover endangered fish while water development proceeds in accordance with federal and state laws and interstate compacts. Today, with its demonstrated success, the Upper Colorado River Endangered Fish Recovery Program has become a model to protect other endangered species.  Its biggest success thus far has been in creating stable populations for the Colorado pikeminnow who is on track to be delisted within the next few years.

In my next post, I will discover the complexities surrounding the Colorado River Delta, its ecological importance, issues that impact it and what is being done internationally to preserve and enhance its existence.

Controlling the River: The Impact of Infrastructure on the Colorado River

In this post, I will explore the development of the Colorado River and how engineering and infrastructure has made the Colorado River the most developed river in the United States. I will also look at the effects of dams on rivers and how the environmental movement has shaped the current management of the Colorado River. 

The Colorado River is considered one of the most controlled rivers in the world. Today, the Colorado River serves water to roughly 36 million people for agricultural, industrial, and domestic needs and without the engineering of various infrastructure, this would not be possible. There are over 29 major dams along the Colorado River with hundreds of miles of canals to divert and deliver the water. 

Please click the link below to visit an interactive Colorado River map showing the various dams and diversions.

Colorado River Map -- National Geographic

One of the most astonishing engineering manipulations of the Colorado River though, is the reservoir basins total storage capacity. Combining all of the reservoirs storage capability, an amount of four times the river’s annual flow can be stored along the river.  This fact has given the Colorado River the nickname, “America’s Nile.” 

Hoover Dam: A Modern Wonder of the United States

View of the Salton Sea within the Imperial Valley
Photo courtesy of marlimillerphoto.com

In 1901, one of the first diversion projects on the Colorado River was completed, the Alamo Canal.  The Alamo Canal’s primary purpose was to bring Colorado River water to the Imperial Valley in southern California in order to irrigate this growing agricultural region. However, in 1905, a series of floods hit this region and washed out the floodgates of the Alamo Canal, allowing the entire Colorado River to flow into the Imperial Valley. It took two years and more than 3 million dollars to close the breech, but not before a 45-mile-long lake was created in the Imperial Valley, now known as the Salton Sea. After this catastrophe, it was realized that a more permanent solution was necessary if the Colorado River was going to be utilized.

Construction of Hoover Dam
Photo courtesy library.unlv.edu

Hoover Dam’s location was decided on Black Canyon, about 30 miles southeast of Las Vegas. Construction on the dam began in 1931 with the removal of 3.5 million tons of rock. (1 ton = 2,000 pounds) Over the course of four and a half years, six of the nation’s largest construction companies and thousands of workers built Hoover Dam. The dam itself raises about 730 feet from its base (imagine a 70 story building) and is about 1,250 feet wide at its peak width across the top. Behind the dam sits Lake Mead, a 247 square-mile reservoir with a length of 112 miles across the largest stretch and the maximum water depth of 590 feet. The amount of water stored behind Hoover Dam would be enough to cover a state like Connecticut in 10 feet of water. 

Construction of Hoover Dam at night
Photo courtesy of library.unlv.edu

In 1928, after a series of investigations on the possibilities of damming the Colorado River, Congress passed the Boulder Canyon Act authorizing the construction of Boulder Canyon Dam, now Hoover Dam, and the All-American Canal to bring water to the Imperial Valley.

The construction of Hoover was a major step towards stabilizing the lower channel of the Colorado River, storing water for irrigation in times of drought, and providing much-needed flood control. Hoover Dam, for this reason, is one of the seven modern engineering wonders of the United States and changed the course of history for not only the Colorado River, but for the West.

Lake Mead behind Hoover Dam
Photo courtesy of wikimedia.org

Era of Dams

The Dust Bowl brought public approval for water projects
Photo courtesy of http://midatlanticgardening.com

Following the construction of Hoover Dam, an era of dam building began. Water developing agencies across the nation, particularly in the West, launched a “forty-year binge” of dam building. Until the mid 1970’s, around 1,000 large dams per year were under construction throughout the world, 500 of these being built in the United States. A large dam is defined as one higher than 15 meters (taller than an average 4 story building). The Great Depression and subsequent New Deal politics initiated the authorization of these water development projects, since such public works projects would stimulate the economy. Not only that, but the 1930’s mid-continent drought, known as the Dust Bowl, helped generate public support for water development projects.

A stretch of the Colorado River Aqueduct
Photo courtesy of lbwater.org

During this period, numerous projects occurred along the Colorado River. Projects not only to store water, but also to deliver water, for flood control, and to generate electricity. The Lower Basin states looked to develop the Colorado River for municipal purposes in this time of growing urban centers. Specifically, the Colorado River Aqueduct, completed in 1941, delivers water 250 miles to Los Angeles and due to the population growth in Las Vegas Valley from Hoover Dam, Las Vegas tapped a pipeline from Lake Mead in 1937. Colorado leads the Upper Basin states in water development projects, the most notable project being the Roberts Tunnel, which diverts water from the Colorado River to Denver.

Construction of the Roberts Tunnel to bring
Colorado River water to Denver, Colorado
Photo courtesy of Denver Water

Without the addition of surface water storage in the Upper Basin, there was no guarantee that the Upper Basin states would be able to use the full amount of water given to them by the compact and thus many reservoirs were built including the Lake Powell, Flaming Gorge, and Navajo. Projects like these were occurring around each bend on the river. In the growing West, water meant a future for urban cities to expand. However, in the 1980’s a new era began that closed the door on major dam building, the environmental movement.

Environmental Movement Shifts Infrastructure Future

The environmental movement began as a desire to manage the natural resources of the land and protect it from over-industrialization. Although the environmental movement began much earlier, the era of large dam building came to a close in 1969 with the formation of the National Environmental Protection Act (NEPA). NEPA set policies that directed all branches of the federal government to protect the environment. Any action planned by a federal agency has to be preceded by an Environmental Impact Statement (EIS), which details the effects of the proposed action upon the environment. The Act also requires an annual report on environmental quality from the President.

Various considerations are needed in the NEPA decision-making process
Photo courtesy of projectpermits.com

NEPA put a halt on large dam projects for a number of reasons. Specifically along the Colorado River, large dams such as Hoover Dam and Glen Canyon Dam have numerous environmental consequences that include direct impacts to the biological, chemical, and physical properties of the river and riparian (banks of the river) environments. Below is a list of some, not all, of the environmental impacts of large dams on the Colorado River.

• Dam walls block fish migrations, which in some cases completely separate spawning habitats from rearing habitats
• Dam walls trap sediments, which are critical for maintaining physical processes and habitats downstream of the dam
• Transformation upstream of the dam from a free-flowing river ecosystem to an artificial flow-restricted reservoir habitat impact aquatic and riparian life, sometimes destroying the system completely
• Changes in temperature, chemical composition, dissolved oxygen levels and the physical properties of a reservoir are often not suitable to the aquatic plants and animals that evolved with a given river system

Diagram of components on a free-flowing river and a dammed river
Photo courtesy of vtwaterquality.org

For these reasons, and many others, environmental groups have altered the management of the Colorado River by stepping in when new actions are proposed to alter the state of the river. Today, infrastructure managers and engineers are placed with the challenge of finding sustainable ways to supply water to the growing West, while also maintaining or bettering the conditions along the river. Unlike in the mid 1900s where the solution to water problems along the river was to build more, today the solution is not in constructing more projects, but rather to manage the current infrastructure in a more sustainable way.

A thriving and healthy Colorado River ecosystem is one
of the many environmental movement aspirations
Photo courtesy of secure2.edf.org 

In my next post, I will investigate the current issues surrounding both endangered species and invasive species along the Colorado River and what is being done in regards to these issues.

Law of the River: Policies Navigating the Colorado River

In this post, I will attempt to layout the very basics of the laws regulating the Colorado River starting with the Colorado River Compact of 1922 and touching on various components of the Law of the River.

How Policy has Shaped the Colorado River

The 100th Meridian is clearly defined by the yellow line down
the middle of the U.S. West of the 100th Meridian, precipitation
is less and highly varied.
Photo courtesy of
http://grist.files.wordpress.com/2008/07/precip.jpg

In 19^th century America, the popular notion of Manifest Destiny, a term for American expansion and the belief that the United States not only could, but was destined to stretch from coast to coast, drove many Americans to settle in the western parts of the United States. As early settlers began to inhabit western America though, it became apparent that there was a great difference between the amount of water on the East versus the West. In the West, there is not only less water, but the water that does appear, in the form of rain or snow, is highly varied. This crucial fact laid the basis to western water law.

Basis of Eastern and Western Water Laws

In the East, water law is defined by riparian rights. Simply put, riparian water law states that all landowners whose property is adjoining to a body of water have the right to make reasonable use of it. In the West, far less bodies of water exist and thus a form of water law called prior appropriations, or a combination of riparian and prior appropriations exists. A simplified way to explain prior appropriations is by the common phrase, "first in time, first in right". 

Photo courtesy of ww.oregon.gov

“An appropriation is made when an individual physically takes water from a stream and places that water to some type of beneficial use. The first person to appropriate water and apply that water to use has the first right to use that water within a particular stream system. This person (after receiving a court decree verifying their priority status) then becomes the senior water right holder on the stream, and that water right must be satisfied before any other water rights can be fulfilled.”


A reasonableand beneficial use, as defined by the prior appropriations includes “municipal and industrial uses, irrigation, hydroelectric generation, and livestock watering. More recently, the concept has been broadened to include recreational use, fish and wildlife protection, and enhancement and aesthetic enjoyment”. Water rights, unique to prior appropriation law, are unconnected to land ownership, and can be sold or mortgaged like other property, whereas water rights under riparian law cannot be sold or mortgaged.

Overview of the Colorado River Basin
Photo courtesy of Professor R. Balaji

Colorado River Compact of 1922

Water law along the Colorado River is complex due to its transboundary nature and high demands for the water, nestled with the arid climate it resides in. Since each state administers water laws individually, the Colorado River Compact of 1922 was formed to initiate cooperation along the river and to allocate the water as to not over use and dry up the river.


The Colorado River Compact of 1922 divided the basin into the Upper and Lower Basins and was written so that the waters of the Colorado River would be divided on a 50-50 basis between the Upper and Lower basins. Each basin is allotted 7.5 million acre-feet of water in perpetuity, or indefinitely. To give a perspective of how much water 7.5 million acre-feet is, one acre-foot supplies water for an average of 2 households for one year.

Photo courtesy of http://greatecology.com

Law of the River

Although the compact attempted to look at the future water needs of the Colorado River Basin, the signers could not foresee the immense urban growth, the movement towards protecting the natural environment, or the implications of climate change in the 21^st century. With the Colorado River Compact of 1922 serving as the foundation, the Colorado River is managed and operated under numerous compacts, federal laws, court decisions and decrees, contracts, and regulatory guidelines collectively known as the "Law of the River."  The Law of the River is very complex so the rest of this blog will touch base on the key aspects of the Law of the River.

Hoover Dam and Power Plant
Photo courtesy of http://lasvegastours.onboardtours.com

Boulder Canyon Project Act (1928)

Reliably providing both the Upper and Lower basins with 7.5 million acre-feet of water annually in such a varying water system would not be possible without storage infrastructure, such as reservoirs. The main purpose of the Boulder Canyon Project Act was to build the first infrastructures on the river to aid in the stability and reliability of water supply along the river. 

The Boulder Canyon Project Act authorized the construction of,

• Hoover Dam
• Power Plant at Hoover Dam
• All-American Canal

Mexican Water Treaty (1944)

The Mexican Water Treaty allocated to Mexico 1.5 million acre-feet of water annually. The allocation was to be increased in years of surplus to 1.7 million acre-feet and reduced proportionately during years of extraordinary drought. The Treaty dealt with quantity and was silent on the quality of water to be delivered which was debated in 1972 with the establishment of Minute 242 and the Colorado River Basin Salinity Control Act of 1974.

Figure 1: Breakdown of allocations by basin
Photo courtesy of http://www.riversimulator.org

Upper Colorado River Compact (1948) and Arizona v. California (1964), U.S. Supreme Court Decree

The Colorado River Compact did not apportion a specific amount of water to each state within the basins. In 1948, through the Upper Colorado River Basin Compact, the Upper Basin agreed upon annually allotting each of the Upper Basin states a percentage of the 7.5 million acre-feet of water. The Lower Basin, on the other hand, could not reach an agreement on the allotment of water to each state so in 1964, the U.S. Supreme Court decided on allocating the 7.5 million acre-feet of water in a similar manner as the Upper Basin, by percentages. Please refer to Figures 1 and 2 to see the breakdown of the Upper and Lower Basin allotments.

Figure 2: Breakdown of total Colorado River water allocation
Photo courtesy of http://www.h2ouniversity.org

Colorado River Basin Project Act (1968)

Under the Colorado River Basin Project Act, the authorization of the Central Arizona Project and other water development projects in the Upper Basin were made. The Central Arizona Project allows the major part of Arizona’s Colorado River allotment to be sent to the south-central part of the state. Overall, this Act took into account the changing future and the need for more efficient storage structures, especially for times of drought, as well as coordinating long-range operation of the reservoirs along the Colorado River. Lastly, this Act undertook programs for water salvage and groundwater recovery along the river.

A stretch of the Central Arizona Project
Photo courtesy of http://arizonaexperience.org

Minute 242 (1973) and Colorado River Basin Salinity Control Act (1974)

Under the Mexican Treaty in 1944, only the quantity of water delivered to Mexico was addressed and not the quality and so, the water entering Mexico was of very low quality. In 1973, Minute 242 was established to set a standard on the quality of water entering Mexico and in order to achieve this standard, in 1974 through the Salinity Control Act, multiple desalination plants and salinity control units were set up along various parts of the Colorado River.

Yuma desalination plant
Photo courtesy of http://www.azwater.gov

Although this is a simple synopsis of the key components of the Law of the River, it is important to keep in mind that the combination of these complex laws are ever-evolving to the changing times. More notably though, is how well the Law of the River stands as a model for managing complex water basins throughout the world by addressing not only the needs of the players involved, but also environmental aspects as well. 

Next time, I will investigate the various infrastructure along the Colorado River and how “taming” the river has allowed for civilization to thrive in the arid and drought stricken region of the Southwest.

The American Nile Running Dry: An Overview of the Colorado River and Water Shortage

Photo courtesy of www.smscs.com

The Colorado River, nicknamed the American Nile, is arguably the most precious asset to the southwestern United States. Supplying water to nearly 36 million people both inside and outside of the basin, irrigating 3.5 million acres of farmland, generating 4,000 megawatts of hydroelectric capacity, and entertaining over 20 million recreationalists and visitors annually, the Colorado River is a lifeline to the Southwest. Today, due to over use of the river, the Southwest faces a water shortage problem in the Colorado River Basin.

Colorado River Facts

Overview of the Colorado River Basin
Photo courtesy of http://obrag.org

Starting in the southern Rocky Mountains of Colorado, the Colorado River extends 1,450 miles across seven U.S. states and two Mexican states where it forms the Colorado River delta and empties into the Gulf of California. Over its journey, the river enters varying climates. Beginning in the mountains of Colorado, through semi-arid regions in Utah, and eventually making it’s way though arid regions of the Sonoran and Mojave Deserts. The majority of the basin is characterized by an arid climate, receiving on average 6.5 inches of rain annually. (This number is the average across the basin with some areas in the Rocky Mountains receiving an average of 40 inches of rain annually to areas in the desert receiving an average of 0.4 inches of rain annually)

The river and its tributaries - the Green, the Gunnison, the San Juan, the Virgin, the Little Colorado, and the Gila Rivers - are referred to as the "Colorado River Basin." The Colorado River Basin drains 242,000 square miles in the United States, or one-twelfth of the country's continental land area, and 2,000 square miles in Mexico, making it the seventh largest watershed in North America. 

Division of Upper and Lower Basins in
the Colorado River
Photo courtesy of www.cejournal.net

The Colorado River Compact of 1922 divided the Colorado River Basin into the Upper Basin and the Lower Basin. The Upper Basin includes the U.S. states of Arizona, Colorado, New Mexico, Utah, and Wyoming from which waters naturally drain into the Colorado River and the Lower Basin includes the U.S. states of Arizona, California, Nevada, New Mexico, and Utah, again from which waters naturally drain into the Colorado River. The division of the Upper and Lower Basins is at Lees Ferry in northern Arizona. 

About eighty-five to ninety percent of the water that flows through the Colorado River originates above Lees Ferry from snowmelt in the Rocky Mountains.

Colorado River Compact of 1922

Example of the Colorado Doctrine
Photo courtesy of coyotegulch.files.com

Conflict over water in the West is not a recent topic. From before the time of Colorado statehood in 1876, the legal right to divert and use water has been deliberated. In 1872, the appropriation doctrine or the Colorado Doctrine was established, laying the foundation of water rights in the West. The Colorado Doctrine states that, “water rights are unconnected to land ownership, and can be sold or mortgaged like other property. The first person to use a quantity of water from a water source for a reasonable and beneficial use has the right to continue to use that quantity of water for that purpose. Subsequent users can use the remaining water for their own beneficial purposes provided that they do not impinge on the rights of previous users”. A reasonable and beneficial use, as defined by the Colorado Doctrine includes “municipal and industrial uses, irrigation, hydroelectric generation, and livestock watering. More recently, the concept has been broadened to include recreational use, fish and wildlife protection, and enhancement and aesthetic enjoyment”. This is what differentiates senior water rights (first users) versus junior water rights (subsequent users). 

Division of the entire Colorado River to each state.
US Department of the Interior Reclamation Bureau,
1971-2005 [USDIRB]

Since each state administers water rights individually and not all of the Colorado River basin states use a pure form of the Colorado Doctrine, the Colorado River Compact of 1922 was established. The compact was created in order to ensure that each individual state would cooperate in managing the river not overuse the water. 

The Colorado River Compact of 1922 divided the basin into the Upper and Lower Basins and allotted 7.5 million acre-feet of water to each basin in perpetuity, or indefinitely. To put into proportion how much 7.5 million acre-feet is, one acre-foot can provide enough water for 2 average households of 4 people for one year.

Hoover Dam from above.
Photo courtesy of photographer Lisa Taylor

The Colorado River Compact did not apportion a specific amount of water to each state within the basins. In 1948, through what is known as the Upper Colorado River Basin Compact, the Upper Basin agreed upon annually allotting Arizona 50,000 acre-feet of water and the remaining amount of water by percentages. The Lower Basin agreed in 1962, by means of the Supreme Court, to divide the 7.5 million acre-feet in a similar way, by percentages. Above is a chart that shows the overall breakdown of the Colorado River. In 1944, the U.S. entered into a treaty with Mexico allotting 1.5 million acre-feet to pass into Mexican territory. 

In order to satisfy the Colorado River Compact, infrastructure such as Hoover Dam and Glen Canyon Dam have been built to store water along the river for future use. In total, all of the reservoirs along the Colorado River can store 60 million acre-feet of water, which is approximately four times the annual flow of the river. 

What is the Problem?

The Colorado River is currently listed as the number one most threatened river on the endangered rivers list. This is because management on the river is far outdated and demand of the river’s water far exceeds its supply. This can be traced back to the Colorado River Compact. The allotments of water entitled to the Upper and Lower Basins was agreed upon based on the rainfall patterns and flow of the river observed in the years prior to the treaty’s signing. However, the only data available on the basin’s annual precipitation and river’s annual flow was from 1910 to 1922. This twelve year period, as shown in the paleo reconstruction of the Colorado River flow, has an unusually high flow average never seen before, so the basis of the Colorado River Compact allotments set the stage for water shortage in the Colorado River Basin. 

Paleo Reconstruction of Colorado River flows.
Graph courtesy of Woodhouse et al., WRR, 2007

The average flow for the Colorado River is around 13 million acre-feet, whereas the Colorado River Compact agreed upon allocations based off of an 18 million acre-feet average flow. Although the average annual flow is around 13 million acre-feet, the flow on the river is highly varied with a range of 6 to 20 million acre-feet of water produced each year. Each of the seven states, and Mexico rely heavily on water from the Colorado River and as of 2013, the Colorado River supplies water to nearly 36 million people. This number increases each year as the Southwest is the fastest growing region in the U.S., so each year the river’s supply dwindles to the point that the Colorado River is drying up before it reaches the Gulf of California. 

Dried up Colorado River Delta. Since 1998,
the river has not reached the Gulf of California.
Photo courtesy of photographer Pete McBride.

The next problem aiding to water shortage in the Colorado River is due to climate change. It is estimated that climate change will reduce the flow in the Colorado River by 10 to 30 percent by 2050. This loss of flow 

U.S. drought monitor shows that the Southwest is in a
severe to extreme drought with some areas in a exceptional drought.
Chart courtesy of http://droughtmonitor.unl.edu

is due to rising temperatures reducing the amount of  

snowfall in the Colorado Rocky Mountains, causing a decrease in runoff to the headwaters of the Colorado River. A reduction in the Colorado River flow will likely cause further drought conditions throughout the Southwest, similar to the droughts seen from 2000 to 2013. In this recent thirteen year period, the Colorado River Basin only produced three years where the runoff reached average or 

above average values.  

Many of the reservoirs along the river have reached record lows in the amount of water stored. Lake Powell, for instance held only one-third of its storage capacity in 2005, the lowest storage ever recorded since 1969. In 2010, Lake Mead was eight feet away from reaching the first “drought-trigger,” which would cause Arizona and Nevada to ration water use as defined in the Colorado River Compact. 

The red and white makings on the canyon walls, known as bathtub rings, show how much water was once stored in Lake Powell. Today, these rings are nearly 100 feet high, as the Southwest faces its second consecutive period of drought.
Photo courtesy of http://picturesandplanetickets.files.wordpress.com

Water shortage in the Colorado River Basin is inevitable due to over use of the water, the arid region in which the basin sits, and ever growing southwestern urban centers. The future of the river is uncertain, however if agreements aren’t met to reduce the use of Colorado River water, the Southwest might just shrivel up its lifeline, a catastrophic event that will have many physical, economical, and environmental consequences. 

Below is a short film titled, Colorado River – America’s Most Endangered River 2012 produced by Pete McBride through AmericanRivers.