River Kennet

Question 1

What is the geology of Kennet’s drainage basin? How does this affect seasonal patterns? How does this impact water stores being used by humans?

Answer 1

1. Consists mainly of permeable chalk.
2. Greater infiltration and percolation, especially in winter months.
3. Groundwater storage becomes more significant as it is likely to hold a significant amount of water.

Question 2

Where did extraction happen historically?

Answer 2

They happened from the upper catchments using boreholes. Boreholes are narrows shafts bored into the ground.

Question 3

Why was water extraction previously unsustainable? Give evidence.

Answer 3

None of the water extracted returned as waste water, leading to a reduction of river discharge. Has led to groundwater discharge exceeding rates of recharge. —> Falling water table & 10-14% of reduction in flows.

Question 4

What settlement has the biggest demand for water from the Kennet river basin?

Answer 4

Swindon has the largest demand for water. It has the largest population at 220,000 people.

Question 5

Where does water extraction happen now? Why?

Answer 5

1. Water extraction now happens from Blunsdon and Farmoor reservoir, connected by a new 18km pipeline.
2. This is due to a notice halting extraction from Ogbourne water treatment works borehole and reducing extraction from Axford borehole.

Question 6

What has been the role of pressure groups at Kennet river basin?

Answer 6

They put pressure on Thames rivers and the local council to have a more serious role, and make sure that extraction does not exceed recharge. They also press for more pipelines to extract elsewhere and aim to protect the surrounding environment in the long-term.

Question 7

How has the River Kennet’s dynamic equilibrium been disrupted?

Answer 7

1. Groundwater extraction has exceeded rates of recharge, and has not been restored via seasonal variation. Instead, it has had a longer term impact by lowering the water table, thus disrupting flows.
2. New pipeline disrupts seasonal variation of flows and variation: supposed to have lower discharge. BUT helps to protect this flow during dry weather. Thus may instead end up leading to exceeding rates of recharge => potential flooding consequences/ rising water table.

Question 8

How has the River Kennet’s dynamic equilibrium been restored?

Answer 8

1. New pipeline however does help to restore water security, signalling that extraction had been exceeding recharge, and thus helps to stop the water table from declining beyond simply seasonal variations.
2. Water deficit has been balanced, and though extraction is still allowed, when excessive, levels gauged are reduced.