Case study - IRBM Case Study - Colorado integrated river management

Question 1

How long is the Colorado River?

Answer 1

2,300 km

Question 2

How large is the Colorado River basin?

Answer 2

637,000 km squared

Question 3

How many different states does the Colorado River supply water to?

Answer 3

8

Question 4

How many major dams and reservoirs does the Colorado River contain?

Answer 4

11

Question 5

How many hectares of farmland does the Colorado River irrigate?

Answer 5

1.4 million

Question 6

Since the 1990’s, what has happened to the average annual flow of the Colorado River?

Answer 6

Since the 1990’s the average annual flow of the Colorado River has decreased by 15%.

Question 7

Why has the basin recently been prone to drought conditions?

Answer 7

The basin has recently been prone to drought conditions due to the effects of climate change.

Question 8

Give some examples of agreements that were reached before 1960 between the states which the Colorado River passes through?

Answer 8

• In 1922, seven states agreed a compact and the basin was divided into upper (source areas) and lower (demand areas) sections for management purposes and water was allocated by state
• In 1944, an agreement was reached with Mexico which defined the water allocation for the country
• In 1956, a comprehensive development plan was developed to cover river regulation, HEP production, water rights and irrigation

Question 9

Give some reasons why conflict has occurred between the states despite the agreements?

Answer 9

• Sometimes there has not been enough water to meet all of the states allocations which has led to disputes
• In 1990, the lower basin US states used their full allocation for the first time
• Drier conditions and a fall in reservoir levels has meant that there is simply not enough water to meet the demand

Question 10

Give some examples of modern agreements that have been reached between the states?

Answer 10

• A new agreement was reached in 2007. Instead of sharing the Colorado’s water, the seven US states divide up the shortages. The amount of water determines the supply that each state receives
• In 2012, an agreement called Minute 139 was signed between the USA and Mexico. It gives Mexico the right to store some of its Colorado River water in Lake Mead. In return, water providers in the Colorado River Basin will be able to purchase water conserved through improving Mexico’s canals and storage infrastructure.