Embed / Share - Multi purpose schemes- The River Colorado
Multi purpose schemes- The River Colorado
Why was it dammed?
How has it affected the lives of the local people?Slide2
Where is the River Colorado?
Now using the atlas- complete your map following the instructions on the sideSlide3
Why was the river dammed?
Much of the area the river runs through is desert and area twice as big as the UK
Early settlers dammed the river to provide water to local cities and towns- much of this comes from the snowmelt in the Rocky Mountains
It also regulated the flow of the river to ensure a constant supply of water to cities such as Las Vegas and Phoenix
25 million people in the SW rely on this supplySlide4
The Hoover Dam
In Boulder Canyon
Lake Mead and Lake Powell are two largest man made lakes in the USASlide5
What are the effects of the dam?
Using the sheet you have be given colour in the bubbles to show the effects of the dam in the following categories
What other effects are there?
400,000 ha of land is irrigated for farming (most of it in California’s Imperial Valley)
Lake Mead and Lake Powell are major tourist centres
Lake Powell offers sailing, power boating, water skiing and fishing and attracts over 2 million visitors a year
The photo above was taken on July 26
year of drought, lake level dropped more than 100 ft- lowest level since the late 1960’s.Slide7
Impacts in Las Vegas
Annual rainfall of 50mm
90% of water from Lake Mead
Much of the water is lavish and wasteful- lawns, parks, golf courses and swimming pools are seen as essential and can only be maintained by irrigation
Major tourist destination- over 37 million visitors a year
Water is becoming increasingly scarceSlide8
So what are the solutions for Las Vegas?
‘Grass for Cash’- the city pays householders $1 for every square foot of lawn they remove
They hope they will replace them with Cacti and other desert plants
Pumping water from aquifers (permeable rocks underground) or oases- but what are the issues with this?Slide9
Aquifers in the Mojave Desert
This is north of Las Vegas
The oases in the desert such as Ash Meadows are rich in wildlife- 239 species of bird, 27 mammals, 20 reptiles, 5 amphibians and 7 fish
25 of which are nowhere else in the world
These are protected as national wildlife refugesSlide10
The potential effects
The Las Vegas Water Authority wants to pump around 2 million cubic metres of groundwater each year from the aquifer
It will lower the water table
Springs will dry up
The unique environment will be destroyedSlide11
How will Las Vegas meet the demands of its growing population and tourism industry?
How important is the natural environment compared to urban lifestyles and jobs?
Why was it dammed How has it affected the lives of the local people Where is the River Colorado Now using the atlas complete your map following the instructions on the side Why was the river dammed ID: 255253 Download Presentation