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Updating flood map for surface water - views requested on publication

Updating flood map for surface water - views requested on publication

Thumbnail Uploaded by Jo Allchurch, 16/04/13 11:51
The Environment Agency are developing their approach to publishing the national surface water flood map and want your views. As you know, under the Flood Risk Regulations the Environment Agency are required to publish surface water flood mapping for areas designated as 'Flood Risk Areas' (there are 10 in England) by 22 December 2013. They are considering when is best for them to publish surface water mapping for the rest of England and need to know your views on the options available. To give everyone (the Environment Agency and LLFAs) time to prepare for publication they need to know what you think by the end of April. More information can be found in the attached briefing.
Tags: flownet surface water environment agency briefing flood map
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HASMUKH PATEL 6 Years Ago
6 LLFA's in NW London are meeting with EA next week and we will be discussing implications on publishing the SW Flood maps.
Mark Young 6 Years Ago
We had a similar meeting last week, which was very helpful and I would like to extend my sincere thanks to the EA team for taking the time to hear our concerns. I got a great deal from the session in terms of the value of the mapping to me as a flood risk practioner, but concerns around the unintended consequences of publication remain. This is largely now a redundant point since the maps have now been produced, but since the duty for surface water flood risk sits with LLFAs, the wisdom of this data set having been produced by the EA, at DEFRAs behest, remains questionable. Given the difficulties and costs associated with validating the data, and in managing challenges and queries, it is regrettable that a full impact assessment of this aspect of the project does not appear to have been carried out. However, since the dataset now exists, it is not reasonable to take the position that it should not be published, given that the principles around freedom of information are now widely accepted. However, concerns relating to issues where data protection implications might exist need to be resolved, and questions relating to whether the resolution of the data can be controlled such that it reflects the confidence we have in the data need also to be considered. But whatever view people hold about the pros and cons of publication, it is absolutely critical that the question of legal ownership (and therefore liability) is addressed before the data is made available. In particular, it is an imperitive since the maps will have a direct bearing on development, and therefore will inevitably influence commercial decisions. It is reasonable to anticipate that planning decisions based upon the maps may be subject to legal challenge, and as such the legal ownership of the data needs to be clear. If the data is to be amended and updated on a regular basis by LLFA's, as occurs with the EA main river maps, then logically the data ownership should sit with the LLFA. Yet this data has been produced by the EA and I would anticipate that, unless LLFAs receive appropriate incentives or are legally bound to take ownership, then surely all LLFAs would be reluctant to accept this ownership and attendant liability. Finally, with respect to the questions regarding the phasing of the publication, the relatively subtle difference in the timings is likely to have little impact. But on the basis that publicity surrounding the first wave of publications might sensitise other communities to eagerly await and then be disappointed by the information, I would favour a single publication date. (this would also give less of an impression that the data has been meaningfully tailored to individual authorities).
Jo Allchurch 6 Years Ago
Thanks Hasmukh and Mark. It would be good to hear others views on this as well.
FM
Former Member 6 Years Ago
The questions that potential usersof the maps should centre around the risks (the effect of uncertainty on their objectives). They need to concider the uncertainties associated with the DEM given the topography and built environment in the locations that it is being used. They need to consider the uncertainties associated with the hydrological data and hydrological modelling used in the generation of the maps. They need to consider the uncertaities regarding the assumptions made about the performance of the minor drainage systems that are not actually modelled. They need to consider the uncertainties associated with the perceptions of the people viewing the maps regarding their accuracy. If they have confidence in the ways that they have identified to manage the uncertainties then they shouldn't have too much problem in buying into the ownership of the risks, but as Mark says the maps will need to be regularly updated. Lets face it you wouldn't want to do due diligence on a company using five year old financial data. That's not to say that the maps are not of use, but if they are full of caviats saying that the uncertainties are significant and that they could result in incorrect locations, extents, depths quantities and velocities, then there will need to be detailed local checks made at each location that they are used.
JD
Jo Diamond 6 Years Ago
Hi all - thanks for your comments so far. I just want to encourage any other comments on this subject, and in particular any issues you have. We're very keen to hear from you all. Hasmukh - I'm glad to hear you're meeting with our local EA team to talk about the surface water maps. We've also been talking to the GLA about the Drain London mapping. Mark - thanks for your feedback on your recent meeting. We are aware of how important the issue of ownership is and we are working on it. We're also got work underway to look at the process for challenges to flood and coastal risk maps and data - this covers our flood maps for rivers and the sea as well as the coastal erosion maps and surface water maps. If anyone is interested in being involved in this, please let me know.
Tom Ghee 6 Years Ago
Having spent a limited amount of time looking at the mapping in my district, I'm at least reassured that the maps appear to generally mirror the flood outlines we encountered in 2007. I struggled to accept the previous AStSWF and FMfSW maps as being realistic indicators of SW risk, both seeming to generally overestimate the problem. With respect to publication/use/ownership of the information I feel LLFA's have to take ownership of the data and the issues arising from it's accuracy. Many of our new legal duties surround the collection, recording, publishing and use of asset and flood risk data - we will never effectively engage with stakeholders on the risks and responsibilities that they face if we don't share the information we hold, however uncertain or inaccurate it might be. Key to all of this is how the insurance industry chooses to use the data - high insurance premiums and potential property blight, based on inaccurate data will kill any chance of an open and constructive relationship with our stakeholders. Insurance assessments need to be more sophisticated, using the available information to assess risk but reflecting the uncertainty in the data.