Water Abstraction Flashcards
When can water problems occur?
When the demand for water exceeds the amount available during a certain period.
Where do water problems tend to occur?
Areas with low rainfall.
High pop dentist.
Intensive agriculture
Industrial activity
In Europe where is fresh water mainly from ?
Underground.
What happens when the pumping of water is happening quicker than it being replenished through rainfall?
Sinking water tables
Empty wells
High pumping costs
Intrusion of salt water from sea
Why is intrusion of saltwater bad ?
Degrades groundwater.
Makes soils not fertile.
Where is saline intrusion happening?
Mediterranean coastlines of Italy, sparky and turkey
Where demands of Tourists are major cause of over abstraction.
What is happening in Malta?
Most underground water can no longer be used for domestic consumption or irrigation because of saline intrusion.
It has resorted to expensive desalinisation plants
Why are sinking water tables bad?
They make rivers less reliable.
Why do sinking water tables make rivers less reliable?
Because many rivers are maintained in the dry season by springs.
But these dry up when water table falls
What does groundwater also help sustain? Thank
Surface reservoirs like lakes.
These are highly productive ecosystems.
Tourist site.
Threatened by over abstraction
What is main cause of groundwater over exploitation?
Irrigation.
Example of irrigation impact.
Italy
Over exploitation of Po River in the region of Milan aquifer has led to 24-40m decease in groundwater level over last 80 years.
Why is water abstracted in London?
Due to industrialisation.
Associated development of groundwater sources.
What happened in 1960s in London?
Ground water levels beneath central London dropped 88m below sea level.
Large depression in water table.
Because of this disturbance in 1960s what happened?
Industries like brewing relocated or were closed down.
What happened in 1990s in London ?
Groundwater levels recovered by 3 m per year in places.
Gradual rebound of water table.
How did rising ground water lead to problems in London ?
Threat of rising ground water on structures in London basin. Like London Underground.
Building foundations.
To mitigate against rising ground water in London what was implemented?
General aquifer research, development and investigation team.
To control water.
Was the GARDIT successful?
Yes
Due to careful management of both abstraction and artificial recharge the rise in ground water.
What are ground water levels like in south London?
Fallen more than 2m .
What are ground water levels like in west London?
Risen due to limited abstraction in this area.
4-8 meters since 2000
