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CCN Flood Risk Workshop on Tuesday 15^th February 2011

Our next CCN Flood Risk Focus Area Workshop will be held at LEC on February 15th in conjunction with the North West Brownfield Regeneration Forum. It will give an overview of the impact and new duties associated with the Flood and Water Management Act and explore the topic from a variety of practitioner perspectives. The day is free to attend with support from CCN and registration is open.

Workshop report

Tuesday 28^th September 2010 at Lancaster Environment Centre

Our event on September 28^th, in conjunction with the RTPI Development Planning Network prompted a discussion across the planning community around developing a general framework and practical guidance for dealing with uncertainty, with a particular focus on flood data, modelling and mapping. Uncertainty could be particularly important in trying to project the impacts of future land use and climate change on flood risk, and the visualisation and communication of this uncertainty could have an impact on decision making within the planning and development communities.

The event attracted almost 30 delegates with a varied range of interest and responsibilities across flood risk mapping and development planning.  Despite being very well advertised by RTPI, few actual planning professionals attended with the majority of delegates present involved in directly in the production/interpretation of flood risk maps.

The day began with an overview of the background to uncertainty estimation methods in flood risk mapping by Keith Beven followed by an overview from Kate Donovan of Project FOSTER – a KE project centred on communicating flood science to a group of Local Authorities in Central England.

Presentations from the meeting are available to view

•  Keith Beven, Lancaster University Sources and understanding of uncertainty in data, modelling and mapping?
• Kate Donovan, University of Oxford Communicating flood science to Local Authorities – An introduction to FOSTER: Flood Organisation Science and Technology Exchange Research

 The facilitated group Discussion Sessions (led by Simon McCarthy) allowed us to explore what aspects of visualising an uncertain flood risk are of particular importance to the planning and development community.

 Discussion Session I dealt with ‘uncertainty in practice’ and 4 broad pre-selected groups (Government Agencies, Planners and Development Practitioners, Academics and Environmental Consultants) were asked to identify how and in what form they incorporated uncertainty into flood risk mapping and how that uncertainty was represented.

The planning group felt that there was no admission and therefore discussion of uncertainty across the profession. It was considered an admission of weakness to admit to ‘not knowing’ and the topic added ’grey areas’ to decision making which relied on definitive yes/no answers. The technical knowledge needed to understand and process the flood map information and construction was well beyond traditional planning knowledge and therefore expert guidance was always needed via Environment Agency staff. Nevertheless it was felt by some delegates that the planning process – as a process of negotiation – could embrace discussions around uncertainty and use them as an opportunity, particularly to incorporate green infrastructure and sustainable regeneration options across vulnerable urban areas.

This view was reinforced by the consultants group who raised the issue that PPS25, and the initial 90 day decision limit, did not allow for adequate negotiation of projects.   Inclusion of uncertainty into the process might help more sensible decisions to be made – albeit that it might take more time and cost more.  It would also help counteract the false impression of precision given by the use of standard prediction packages and the resulting crisp maps – although it is normal practice to carry out some sensitivity analysis of results based on professional judgment, even if results are not often communicated to users.

Subsequent Discussion Sessions were conducted in mixed delegate groups.  The first of these aimed to identify sources of uncertainty and highlight which of these were most difficult to quantify. The second examined communicating and interpreting flood risk messages using mapping tools and the third centred on the need for guidelines for the development and planning community to help them embrace uncertainty within decision making.   There was felt to be a concern that including uncertainty might simply lead to the use of worse case scenarios (i.e. less successful planning applications). There is still a need for standards to work to for different purposes, but including uncertainty might reduce the inflexibility of the current process that allows a crisp line on a map to dominate local knowledge.  It would be important to communicate the assumptions used in producing uncertain flood risk maps to properly evaluate risk and choices.

It was felt that guidelines were most useful for the flood risk assessment professionals who are charged with producing flood risk maps.  Future training opportunities that covered a non-technical overview of flood risk mapping methods was the preferred way forward for the planning community. It was also highlighted that the impact of flood risk on development and decision making as a discrete topic should be embraced across Planning Schools and planning qualifications to ensure looking forward that there is an improved understanding of the implications of flood risk across the profession.

It has been a busy couple of weeks for me attending both the in Beijing followed by the in Seville. Personally I found the former more stimulating, perhaps because it was more out of my comfort zone – closer to the plant than the water – with some interesting papers talking about the molecular advances in plants and how these can help potentially increase the efficiency of P use in a world with decreasing P reserves. Moreover, apart from the obvious guilt I feel for my carbon footprint, it seems such a shame that we had two P conferences on different sides of the world within a few days of one another.

The more I think about these isues the more important it is that we seek a unified and integrated view on these issues, rather than fragmenting into the ‘soil-plant’ and the ‘soil-water’ world. Perhaps we need a conference entitled simply ‘Phosphorus’ next?

Phil.

It seems that trying to provide estimates of the uncertainty associated with predictions of catchment change may not be enough as an input to the decision making process.  At a meeting this week on Challenging Models in the Face of Uncertainty, organized by the Centre for Research in the Arts, Social Sciences and Humanities (CRASSH) in Cambridge, it was suggested in a succession of talks that all such outcomes are culturally conditioned – both in the assumptions that are made and in the interpretation of the results.  These will depend, following the Cultural Theory grid/group characterisations of Mary Douglas, on whether you are a combination of hierarchist or egalitarian, individualist or collectivist.   I have a beard so I must be a egalitarian collectivist.  Different groups will frame decisions in quite different ways and since it is impossible to be totally rationalist about the application of science to real world problems (in part because of the incomplete knowledge and epistemic uncertainties discussed in earlier blogs), there is plenty of scope for doing so. 

The issue of climate change underlay a lot of the discussions, but many other policy areas were used as examples, from badger culls to GM crops and security against terrorism.   A particular issue in respect of climate change resonating with the blog after Hydropredict2010 was the choice of discounting rate in cost-benefit analysis.   We do not know what future discounting rates should be but different assumptions might make a lot of difference to the ranking of options.   It is also easy to see how the choice of parameters in any model of catchment change might also be influenced by desired outcomes.   Steve Raynor (Oxford) gave the example of the Chesapeake Bay study.   He suggested that the (highly complex) model of the system and its catchment areas shows a steady increase in water quality in the bay as a result of the improvement measures that have been taken.  He also suggested, however, that the observations gave no such evidence of any increase in quality.  The modeled improvements were, however, politically expedient in getting continued Congressional funding for the project from year to year.

So there was much discussion about how to avoid the conflicts between world views that this post-normal framing of scientific rationality implies.   Suggestions in different presentations ranged from opening up the dialogue to a plurality of views in a deliberative discourse to invoking a context of common interest in defending national security or interest.

A model and its predictions might be just one element in a deliberative discourse between different groups who might choose to use it (or equivalent models) in different ways.  While no model could possibly capture the full complexity of a catchment system (which might itself provide an element of surprise in its responses to forcings that have not been observed before), to my mind that really does not mean that the modeler should not be as rational as possible in providing advice to decision makers.  We should always, of course, reflect on the fact that this rationality is conditional; it depends on the particular perceptual models of those who use it, models which have been shaped by histories particular to individuals, and the particular observations available for evaluation.   There is no common agreement about how catchments should be modeled, only a wide range of software packages that might be used for different purposes.

So being rational then comes down to using models that, as far as possible, get the right results for the right reasons.   This is a valid endeavor in itself, even in a post-normal science world with culturally conditioned assumptions.   There remain many issues about how to test whether we can get the right results for the right reasons (see, for example, Beven, 2010) and in communicating the assumptions and limitations of the model predictions to users, but this is the nature of trying to do science properly.   An uncertainty analysis can then provide a framework for both testing models as hypotheses and being explicit about assumptions.   I have the impression that some sociologists of science would see this as only another means of the scientist trying to establish power and authority in shaping policy (with some implication that this authority might not be justified).  To me, it is simply an exercise in being as scientifically honest as possible.  How the resulting predictions might then get used in a (more or less) inclusive deliberative decision process is a quite different issue but what we should not do is to conceal the limitations and uncertainties of model predictions.  That would not be a good long term strategy.   As Andy Stirling (Sussex) put it:  there is widespread empathy for humility in the role that science can legitimately play in decision making.

Reference:

Beven, K J, 2010, Preferential flows and travel time distributions: defining adequate hypothesis tests for hydrological process models, Hydrol. Process. 24: 1537-1547 Com/marina zlochin and we cannot simply assume that english will remain the world’s dominant language