Integrated Management of Floodplains
Title: Integrated Management of Floodplains
Client/Sponsor: The Rural Economy and Land Use Programme (RELU) - jointly funded by ESRC, BBSRC & NERC.
Cranfield participants: Professor Joe Morris and Dr Tim Hess
Contact:mailto:j.morris@cranfield.ac.uk
Partner organisations: The Open University, The River Restoration Centre, Ecological Solutions.
Image: © Copyright Simon Ledingham and licensed for reuse under this Creative Commons Licence.
The problem:
Land drainage and flood defence in floodplain and coastal areas have been an important component of Government support for farmers in Britain. More recently, however, changing priorities in rural and environmental policy, evident for example in the Reform of the European Common Agricultural Policy, the Water Framework Directive and new strategies for managing flood risk, are encouraging a re-appraisal of land management options for floodplain areas.
This project explores the causes, processes and consequences of change in land and water management in lowland floodplains previously engineered for flood defence purposes in order to inform future decisions on sustainable management.
The project:
The study seeks to explain changes in land and water management over the last 40 years in eight selected floodplain areas that were previously served by agricultural flood defence schemes. This involves stakeholder and institutional analysis, farmer interviews, field observations, modelling of hydrological and related ecological processes, and analysis of farm incomes. The influence of agricultural policy, interacting with farmer circumstances and motivation, is also explored.
Using a mixture of scientific perspectives, options for future land and water management are identified for the study sites. Opportunities for achieving a wide range of benefits through the management of water regimes on floodplains are assessed for each site. Such benefits relate, for example, to farming, biodiversity, amenity, flood management, water quality and the wider rural economy. The study informs strategies for floodplain management, helping to develop approaches that are appealing to major stakeholders. The Ecosystem Functions, Uses and Values Framework has been used for the classification and valuation of benefits of different management scenarios of floodplains.
A methods framework for analysing the physical and financial performance of farming under alternative water (flooding and water level management) regimes has been produced and applied to 8 study sites. For each site;
The impacts of different management regimes on the delivery of ecosystem goods and services were estimated through scenario modelling. For each scenario the water management was adjusted to maximise one of the following objectives: maximum agricultural production, maximum biodiversity within agricultural system, maximum biodiversity without an agricultural system, maximum flood water storage, maximum farm income and compared with the baseline (2006) situation.
Hydrological monitoring of field water table position has been carried out over 18 months. Data have been collected from on-site transducers and processed to estimate water level movements, and to calibrate hydraulic models used to represent seasonal water regimes as part of the scenario analysis. Typical soil hydraulic properties have been determined for each site form published soil data. A field water table model has been defined and the water table positions for each site have been modelled with and without under-drainage. Data have been collected from on-site transducers and processed to estimate water level movements, and to calibrate hydraulic models used to represent seasonal water regimes as part of the scenario analysis.
Ecological assessments have been completed, drawing on previously collected field survey data.
Main findings:
The scenario outcomes highlight synergies and conflicts between ecosystem goods and services delivered by lowland floodplains. There is clear synergy between agricultural production and floodwater storage on both sites as shown in the scenario maximum floodwater storage. However, intensive agricultural production generates relatively high environmental impacts such as high greenhouse gas emissions, high risk of nitrate leaching and low biodiversity.
The financial performance of different land uses under each scenario is sensitive to farm output and input prices and agri-environment payments. This has implications for the design and implementation (i) of hybrid or composite land and water management scenarios that will be beneficial and robust under a range of future possible conditions, and (ii) of policy and support regimes that will make such scenarios appealing to the main stakeholders, especially land managers, conservationists, flood managers and local communities.
Publications:
- Posthumus, H., Morris, J., Hess, T.M., Neville, D., Phillips, E. and Baylis, A. (2009) Impacts of the summer 2007 floods on agriculture in England. Journal of Flood Risk Management. 2009:1-8.
- Rouquette, J.R., Posthumus, H., Gowing, D.J., Tucker, G., Dawson, D.L., Hess, T.M. Morris, J., 2009. Valuing nature-conservation interests on agricultural floodplains. Journal of Applied Ecology 46: 289-296.
- Reed, M.S., Graves, A., Dandy, N., Posthumus, H., Hubacek, K., Morris, J., Prell, C., Quinn, C.H., Stringer, L. 2009. Who’s in and why? A typology of stakeholder analysis methods for natural resource management, Journal of Environmental Management 90: 1933-1949.
- Morris, J., Bailey, A.P., Lawson, C.S., Leeds-Harrison, P.B., Alsop, D. and Vivash, R. 2008. The economic dimensions of integrating flood management and agri-environment through washland creation: a case from Somerset, England. Journal of Environmental Management 88: 372-381.
- Posthumus, H., Rouquette, J.R., Morris, J., Hess, T.M., Gowing, D.J., Dawson, Q.L. 2009. Integrated land and water management in floodplains in England. FLOODrisk 2008 Conference. Oxford, 30 September – 2 October 2008. In: Samuels, P. et al. (eds.) Flood risk management: Research and practice. Taylor & Francis group. London.
