Coastal Barrage - Cardiff Bay Barrage Flashcards
What is a coastal barrage?
Hard engineering scheme to prevent coastal flooding.
What is the function of coastal barrages?
They protect estuaries against the sea in locations with a high tidal range.
Acts as dam across estuary preventing the incursion of seawater.
As well as protecting from flooding what else do dams do?
They create large freshwater lakes behind them - land reclamation schemes.
What is significant about the Severn Estuary and the Cardiff Bay?
They have the second largest tidal range in the world - 14km.
What happens at Cardiff bay at low tide?
Make bay inaccessible by water for up to 14 days.
Mudflats only visible - unsightly and smelly.
What was the main problem in the bay?
Common tidal flooding in the Inner Harbour due to leaky lock gates.
Describe the appearance of the barrage?
s-shaped tidal dam 1.1km long.
800m long embankment constructed from sand/rock.
300m concrete section containing locks, sluices, fish passes.
The inland face of barrage is…
Landscaped to provide linear park.
The seaward side of barrage is…
Protected with rock and stone armour.
Why are sluice gates important?
Dissipate wave energy.
What do the sluice gates do on the cardiff barrage?
5 sluice gates release flow of the Taff and ELY rivers out of the bay.
3 sluies are 140m long, 10.5m wide.
2 sluices are 40m long, 8m wide.
When did the project occur?
Thursday 4th November 1999.
How much did the project cost?
£220 million - economic disadvantage.
What did the tidal mudflats turn into?
Freshwater lake - environmental advanatge.
How much will the artificial lake cost?
£9 million and £12 million maintain every year - eco disad.
Reasons for the barrage?
5
Decrease river flooding and tidal flooding - Ely&Taff controlled.
Improve quality of life of community - attract industry.
Creation 30,000 jobs, private investment, sports village.
Fresh water lake aesthetically pleasing.
Reduction in pollutants.
Environmental conflicts.
Environmental agency made sue flood defence, water quality, fishery issues properly addressed.
Freinds of Earth - ‘barrage destroy wildlife’
Opponents angry at amount of money spent on project.
Environmental solutions.
Designated SSSI.
Home to 6,00o wading birds.
Gwent Wetlands Reserve habitat for wading birds.
Social conflicts.
Locals feared their houses could be damaged from higher water levels.
Contaminated sites would flush underground posing risk to human health.
Social solutions.
Compensation given to locals for any damage.
Authority installed pumping stations.
Solutions to fish danger.
Specifically designed fish pass to encourage marine life in bay allowing salmon/trout to return to rivers and breed.
Name 3 people who opposed the barrage?
RSPB.
Farmers.
Friends of the Earth.
Name 3 people who supported the barrage?
Local businesses.
Local government .
Unemployed.
