Alex Stephenson, chairman of the British Water Suds Focus Group, explains why we have to start using some joined up thinking in order to deal with storm water runoff.

DURING the last decade, we have had to deal with the water quantity and quality problems associated with flooding more and more often, but the severe droughts and water shortages suffered in some parts of England during 2006, particularly in the South East, were a change from this pattern, adding a whole new challenge for us to get to grips with as a nation.

We had barely taken down the Christmas decorations and recycled our Christmas trees before the effects of heavy and prolonged rainfall had again hit many of the areas that suffered during the summer floods of 2007. Some of the unfortunate house owners, in these areas, have not even had the chance to complete their building repair work and return to their homes from their temporary caravan accommodation where they have spent their last six months.

By the time we reached the middle of January, Environment Agency (EA) flood warnings were fast approaching 100 across the west and south east of England with major transport disruptions occurring on many occasions within the space of a week.

Motorways have been closed due to surface flooding and many trains cancelled with the familiar site of temporary flood defences being erected in an attempt to protect properties from the rising waters. Rainfall of more than 30mm fell in many places within the space of a few hours, very similar to the deluges experienced last year.

There has been a lot of activity since those summer floods of 2007 which were linked, in one way or another, to the deaths of 13 people, and many people and organisations have been investigating exactly why we suffered so much and trying to find out what we can learn. During August 2007, Sir Michael Pitt was asked by ministers to carry out a review of the flood-related emergencies which occurred and his interim report was published just before Christmas with the final report due to be published later this year. The initial report was produced in order to identify the issues that need the most urgent action, as well as setting out the direction for the remainder of the review. Consultation on this interim report will also be sought prior to publication of the final report.

His report highlights the fact that the floods during June and July 2007 were a wake up call and that flood risk is here to stay. It also recognises the findings of other reports such as Stern and Foresight, which predict climatic change and state that this country can expect more extreme weather, with periods of intensive rainfall.

Pitt’s report contains several recommendations and many interim conclusions, amongst which are some of interest to anyone dealing with stormwater runoff issues and sustainable drainage systems, which are systems that help to deal with excesses of water by mimicking natural drainage patterns. There are many sensible and very encouraging conclusions within the report, one of which proposes that the Government, as part of its Water Strategy, should resolve the issues around which organisations should be responsible for the ownership and maintenance of sustainable drainage systems.

Sustainable drainage systems are finally becoming well established in managing surface water runoff from new and existing sites, and the vast majority of stakeholders agree that dealing with surface water in a more sustainable fashion is a positive and desirable move.

However the uptake of these methods, used to deal with water in the building and construction industry, is partly hampered by current conflicting and unclear guidance on Sewers for Adoption, the Water Industry Act and the Building Regulations and the subsequent unwillingness of water companies to adopt many sustainable drainage techniques.

British Water represents a broad spectrum of organisations involved in the design and supply of sustainable drainage systems; including most of the major water related consulting engineer practices as well as the leading suppliers of proprietary systems. The Suds Focus Group was started several years ago and includes representatives from various government organisations such as the EA and the Department for Communities and Local Government (DCLG) as well as British Water member companies.

The Focus Group aims to overcome some of the barriers and challenges to the uptake of sustainable drainage and help empower stakeholders with viable sustainable solutions and methods that can assist. There are many tried and tested proprietary products available, or “hard” Suds. These are often ignored or overlooked due to a misplaced belief that sustainable drainage has to be above ground and include open water and vegetation, or “soft” Suds, such as ponds, grassed swales and green roofs. The use of hard Suds can make sustainable drainage systems more readily adoptable in many circumstances and prove particularly useful in providing the much needed storage capacity required in our drainage systems to help deal with excessive rainfall and flooding problems.

There is no doubt that many aesthetically pleasing amenity facilities have been provided as part of sustainable drainage schemes in recent years and most people would agree that dealing with surface water runoff in the most natural way possible is a commendable objective. However, it is clear that this sort of approach is very often not possible or feasible especially in urban areas or where space is at a premium. Designers are often struggling with the dichotomy of providing sustainable surface water drainage at the same time as complying with housing density requirements or minimising flood risk.

Many excellent example sites exist which demonstrate how hard and soft Suds can be used either together or in isolation to provide the requirement to mimic natural drainage patterns and provide the quality improvement requirements that will be driven by the Water Framework Directive (WFD).

A recent mission to the US, carried out by members of the British Water Suds Focus Group, reported on a wide range of findings and made many recommendations relating to sustainable drainage. Relevant examples from Portland, Oregon, Seattle, as well as the UK were shown to show how much can be achieved in the UK especially with the buyin of the local residents and through public engagement.

However, we are missing genuine opportunities to make significant progress in providing sustainable drainage and also to begin responding to the upcoming challenges set by the requirements of the WFD and the Code for Sustainable Homes recently published by the DCLG. This is due to entrenched ideas and a lack of knowledge in some areas.

Some of the aims and objectives of the WFD can be achieved with an integrated approach to the use of natural and sustainable drainage and source control techniques. Rainwater Harvesting (RWH) would also help greatly to provide the required water efficiency requirements of the Code for Sustainable Homes which should also be expanded to cover all buildings and not just new domestic dwellings.

Legislative and fiscal incentives would provide many of the necessary drivers to achieve wider uptake of sustainable drainage and RWH. Also, if we are to realise the full potential of sustainable drainage, it is very important that adoption and maintenance issues are overcome and that stakeholders are encouraged to consider all the options available, including some of the excellent proprietary systems available. Some of the best examples have been produced where engineered or hard systems have been used in conjunction with natural or soft Suds, often the only way to satisfy all the quantity and quality requirements of a sustainable drainage system.

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