An expert from the Environment Agency describes what to look for as the source of the River Thames. From dry channels to flowing water, she monitors where the river begins. She describes why the source of the Thames moves and why it is important to analyse it.

This clip is from:
First broadcast:
5 September 2010

Students could draw a diagram which helps to explain why the source of the Thames changes. Students could investigate further why ground level changes; they could draw a table with two columns, one for human reasons and another for physical reasons.

Students could also investigate further the terms this clip uses - what terms would describe the type of rock which is able to hold water? What different routes could the precipitation take to become groundwater?