CASE STUDY - London And The Southern Basin (relationship Of Water Supply To Physical Geography) Flashcards
1
Q
What was the Thames river basin classified as?
A
A region suffering ‘severe water stress’
2
Q
How many people live in the Thames Catchment? Describe the demand.
A
9 million residents - demand of 2.6 billion litres of drinking water.
3
Q
Describe the climate of the Thames Catchment.
A
- One of the driest regions in the UK receiving only 690mm on average annually - 440mm is taken up by evapotranspiration leaving only 250mm available for the population and environment.
4
Q
Describe the geology of the Thames Catchment.
A
- The chalk acts like an acquifer and provides base flow to the tributaries of the river Thames
- The water levels of the underground acquifer have dropped so significantly over recent years that bore holes are required to be 200m deep and hydrostatic pressure can no longer be relied upon to power the foundations
5
Q
Describe the drainage of the Thames catchment: what percentage of London’s water supply is taken from the River Thames? Where is the remaining 20% accessed?
A
- 80% from the River Thames upstream of Teddington Weir (river abstraction).
- 20% is provided by groundwater abstraction
- In central and east London groundwater levels have by approximately 5-7m since 2000 due to increased abstraction
6
Q
What are some potential issues of the future?
A
- London’s population is projected to grow from 8 million now to 9million + by 2031
- London’s climate is projected to change - autumn, winter and spring will be wetter but spring will be drier - challenges in collecting water and making it last through the dry summers.
7
Q
How might the risks be minimised in the Thames catchment? Name a strategy.
A
- The City of London Corporation’s City Plan 2040 includes a London Sustainable Drainage Action Plan emphasising the need for SuDS in minor and major environments - using green roofs, permeable pavements and rain gardens to reduce runoff.
