Flooding


	Flooding
	Causes Surface run off-a river channel surrounded by steep slopes causes fast surface run off. Lack off vegetation such as trees to intercept precipitation. A drainage basin of impermeable rock, ( this means that water cannot percolate/ soak into the rocks and will influence a faster surface run off.) A drainage basin in an urban area - these consist largely of impermeable concrete, which encourages overland flow. Drains and sewers take water quickly and directly to the river channel. Houses with sloping roofs further increase the amount of run-off.	Effects Homes, businesses and cars belonging to more than 1,000 people were swept away. Income from tourism was lost. This had an impact on livelihoods and the local economy. There were vast numbers of subsequent insurance claims. No lives were lost, partly due to the rapid response of the emergency services.
	Overall summary (based on the Boscastle floods - uk - 2004)

Surface run off-a river channel surrounded by steep slopes causes fast surface run off.
Lack off vegetation such as trees to intercept precipitation.
A drainage basin of impermeable rock, ( this means that water cannot percolate/ soak into the rocks and will influence a faster surface run off.)
A drainage basin in an urban area - these consist largely of impermeable concrete, which encourages overland flow. Drains and sewers take water quickly and directly to the river channel. Houses with sloping roofs further increase the amount of run-off.

Homes, businesses and cars belonging to more than 1,000 people were swept away.
Income from tourism was lost. This had an impact on livelihoods and the local economy.
There were vast numbers of subsequent insurance claims.
No lives were lost, partly due to the rapid response of the emergency services.

(based on the Boscastle floods - uk - 2004)

Get Revising