River Lea SUDS Flashcards
(12 cards)
Why are SUDS needed in London
- Manage rainfall
- Replace impermeable surfaces with sustainable drainage systems.
- Improve water quality
- Manage flood risk
- Reduce surface water
Sustainable drainage techniques used at River Lea
Rainwater harvesting - capture rainwater in tanks.
Bio-retention - landscape features to hold surface water.
Permeable pavements - Allow water to pass through and infiltrate into the ground.
- Oversized piping.
Where is river Lea located
Flows to Stratford
Regenerated with the Olympic park for 2012 Olympic games.
How does the river lea pose flood risk (before regenetation)
Channel topography encourage flow conveyance and pushes issues downstream to areas the water can flood out of bank.
How has river Lea been reprofiled to reduce flood risk.
Contaminated land was treated and new river bank profiles created.
Banks lowered and reconnected channel with its flood plain.
areas of land lowered to create controlled floodplains.
Vegetation cleared to open up river for public access.
Olympic park SUD scheme
North park wetland feature will form a wildlife haven for plants and animals, runoff generated, filter drains installed to capture runoff.
Benefits of Olympic park scheme
Design took climate change into account, sources of surface water contamination found, opportunities to enhance biodiversity, materials used were sustainable.
Benefits of river lea SUDS
New bank profiles created flood storage for 1 in 50 year flood events.
Water conveyance improved reducing how quickly water passes through system - good to reduce flooding in the 600mm rain expected in London in 2026
New bankside habitat created, enhancing biodiversity.
Locals reassured lower flood risk.
Total cost of river lea regenetation
50 million
Dredging
Digging out old material from under the river and moving it elsewhere. Completely reshaping river ecosystem from scratch.
Negatives of the River Lea SUDS
Destruction of Existing Habitats: In some cases, natural or semi-natural habitats were disturbed or removed during redevelopment.
Ongoing Pollution: Despite SuDS installations, the River Lea still faces challenges from urban runoff, sewage overflows, and industrial pollution
Afforestation
4,000 new trees planted around the banks of the river lea to increase infiltration of the soil and decrease surface run-off, thus flood risk
