Enfield - Urban Drainage Flashcards
Where is Enfield located?
North London
Why is Enfield susceptible to flooding?
The area is heavily urbanised with impermeable surfaces
This has increased surface runoff and channel flow
How many homes are at risk of flooding?
9,000
What has surface runoff caused to the river?
It has increased pollutants like oil and heavy metals from the roads
What percentage of houses have wastewater pipes (e.g. toilets, showers and dishwashers) that lead directly into the River Lea?
10%
What were the aims of the 2012 river restoration project?
Reduce flood risk and impacts of floods
Reduce surface runoff to prevent water pollution
Provide more habitats for wildlife and new recreational areas for residents
Which types of SUDS have been used to help restore the river system?
Vegetated trenches have been created around roads to absorb runoff and decrease flood risk
Rain planters have been created in school - these collect and manage the flow of water into drains
Wetlands have been constructed to improve water quality e.g. reed beds were created around Salmons Brook
Which groups have helped to fund the project?
DEFRA (Department for the Environment, Food and Rural Affairs) and Thames Water
How much did the project cost?
£60,000
How have local residents helped the area?
Volunteers have been involved in litter picking and wildlife monitoring
How have local schools been involved in the project?
They have been educated on water management by Thames21.
In 2012, 1,000 students were involved in litter picking and wildlife monitoring
How successful has the project been so far?
Flood risk seems to have been reduced e.g. high rainfall in winter 2013/2014 did not cause significant flooding
Ammonia levels have reduced by 67% and Nitrogen levels by 43% at Salmons Brook
Populations of eels and some species of insects e.g. dragonflies have increased
How has the project been unsuccessful?
Pollution levels are still high, and litter is still a huge issue in the area
