CS 10-11- Tewkesbury Flood

Concrete- makes the ground impermeable.

Steep-sided channel- faster surface runoff which shortens the basin lag flow time.

Deforestation- less vegetation interception.

Drainage basin made largely from impermeable rock- prevents water percolating through the rock layer.

Anything that reduces infiltration and increases surface runoff.

Rained more than 387mm in 3 months.

Slow moving low pressure.

Ground was saturated from previous storms preventing through flow.

Drains couldn't cope with the amount of rain so water ran quickly into the river.

Large catchment area (big drainage basin so more water is collected).

On a big confluence (River Severn & Avon).

Farms in upland Wales had installed drainage to improve pasture which meant increased discharge affected Tewkesbury further downstream.

40,000 without electricity.

10,000 motorists stranded on the M5.

500 stranded at Gloucester train station.

350,000 without tap water due to the flooding of the Mythe water treatment plant.

5,000 homes and businesses were flooded.

825 homes were evacuated meaning people had to stay in temporary accommodation (e.g. hotels, caravans or with family).

£11 million worth of crops were destroyed.

Cost the county £50 million.

Higher plug sockets- reduces risk of electrocution.

Built on higher foundations- prevents water from entering the house.

No carpets- flood water would soak in and cause mold and water damage. Wooden floors mean getting rid of flood water would be easier. Yock varnish is used instead of regular wood

Raised shelves- so that valuables cannot be damaged by flooding.

Metal barriers to easily fit in windows and door- stop water from entering the house.

Permeable gravel drives- ashfelt and block pathing allows water to perculate into the ground, reducing build up in driveways.

Dredging (like in Somerset)- This rids the river of slit so it can hold a larger volume of water.

Fill field drains with straw- keeps the moisutre in the drainage basin and means lag time is longer.

Diversion spillways- the pumping of water to other places such as Kempsie.

Afforestation- increasing vegetation inception.

Force flooding to occur upstream- allows flooding upstream, avoids urban areas.

Levees- give room for the river to flood without negatively impacting the surrounding area (the further away they are the better).

Flood gates- open and close easily when there is a flood warning. They are cheap and always there.

Demountable flood barriers- removable walls put in place when river levels rise. They're removed when there are no risks. However these are expensive to put up and take skilled workers.