Making space for water
Urban flood risk and integrated drainage
River Aire (City of Bradford Metropolitan Council)
Pilot Summary
In recent years there have been notable incidences of fluvial and pluvial flooding within the River Aire catchment in Bradford and Leeds. Initial local assessments showed that flood risk due to a combination of climate change and urbanisation is likely increase in some areas such as Bradford City Centre. The local assessments also identified that some approaches to maintaining acceptable levels of flood risk may have deleterious effects elsewhere in the River Aire catchment. The Leeds City Region is likely to remain the most significant driver of the Yorkshire and Humberside Region’s economy. Job growth around 87,000 is expected within the area by 2016 and housing growth in Leeds and Bradford is now expected to be over 120,000 by the mid 20 20s, representing a 20 – 25% increase in housing stock. The River Aire Strategic Study used models to assess the current and future flood risk and water quality impacts resulting from land use and climate change. It investigated adaptation strategies to satisfy flood risk and water management needs in the urban areas and the River Aire corridor and how they could be applied within the context of local development frameworks. It also reviewed current non structural responses to flood risk and emergency planning and to consider alternatives. The project team has included partners from local authorities, the local water company and the Environment Agency.
The study has predicted that over a time scale up to 2085 in the study area there will be an:
- Increase in the number of vulnerable locations by approximately 40%
- Increase in the surface water flow volume by around 100%
- Increase in the frequency of surface water flooding at vulnerable locations by around 200% as a result of climate change and increased urbanization.
The study also predicted that increased flows from urban areas would impact on the water quality of local receiving waters, especially in the long term through the combination of larger and more polluting discharges from urban drainage systems and potentially lower discharges and higher temperatures in receiving waters There is a need for further knowledge to quantify these impacts for different catchments. However, recent measures taken to reduce the impact of combined sewer systems on the aquatic environment will mitigate short term problems.
The project team identified actions that a range of stakeholders could take to mitigate and adapt to these pressures. These included both structural and non structural approaches. The study identified that management of surface water on the surface can be cost effective, but recognizes that there is a need to learn how to do this effectively at a strategic level and over a long timescale. The role of development control was examined, and highlighted the need for better training and the need to examine the impacts from permitted development at a strategic level. Emergency planning in the response to flooding was well developed, but the need for better engagement with vulnerable communities before flood incidents was highlighted. Some flood risk management practices appear to be more beneficial than others at a strategic level, and the study identifies a need for improved knowledge in this area.
The study focused on integrated approaches and has identified the importance of communication and benefits that the exchange of information between partners can have in terms of better understanding urban flood risk at a strategic level. Members of the River Aire partnership are willing to work together to support and enhance the approaches identified in the study and are exploring ways of doing this.
The study identified the following barriers to the implementation of action which can reduce urban flood risk at a strategic level:
- Partners may be reluctant to share knowledge, if the information could be mis-interpreted at a later date.
- There is still a need for clarity about the roles and responsibilities of the different partners in land and water management at a strategic level.
- There is a need for developing multi-disciplinary approaches within organizations and between organizations.
- There is a need for funding for different stakeholders to enable the sharing of information and experiences effectively so that knowledge about the key drivers of urban flooding can be disseminated effectively to all those with a role in the land and water management within urban areas.
Outputs
Page last modified: 25 June 2008
Page published: 5 March 2007