Risk assessment and risk management for small urban catchments
A case study exploring the effectiveness and limitations of non-structural measures (NSMs) for flood mitigation in small urban catchments.
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Details
Objectives
This project aims to identify the efficiency of various methods of flood information in increasing risk awareness and readiness for appropriate response on the part of stakeholders in urban areas. This case study covers flood management in Heywood, Greater Manchester where storm-induced surface water flooding in 2004 and 2006 affected 200 homes. There was no previous history of flooding and the most likely causes of these flood events were:
- urban infill
- an ageing drainage system
- two culverted urban streams
- high intensity storms
This project:
- explores the opportunities and limitations of non-structural measures (NSMs) for flood mitigation in small urban catchments
- assesses the effectiveness of physical and ecological modifications to drainage systems (from green roofs to channel changes) in managing the risk of flooding in urban areas
- assesses the social, economic and environmental effectiveness of NSMs in managing flood risk in developed urban areas
Outcome
This project contributes to our understanding of the causes of flooding from small, often hidden, urban rivers and streams. It improves the evidence base for selecting effective ways to manage such small urban catchments. In heavily urbanised areas, the scope for NSMs to manage flooding is potentially limited, but good urban design and increased risk awareness may offer opportunities.
This project develops a methodology for the effective application of NSMs in urban environments. The results will be of value to:
- urban planners
- regulators
- water companies
This project provides regulators with a planning framework, which may influence the investment decision of local authorities and water companies with asset management responsibilities.
The findings from the case study have informed the inquiry into flooding by the House of Commons’ Environment, Food and Rural Affairs Select Committee. The outputs of the research will be integrated into the findings of the wider ERA-Net CRUE collaborative research project.
This project ran from 2006 to 2008 at a cost of £63,300.