SUDS offer solution to rainfall run-off

'Summer this year is going to be warm and dry.' Regardless of the accuracy of our long-range weather forecasters, we still have to contend with the fact that the UK climate is an unpredictable mix of rain and sunshine - sometimes simultaneously! One thing is for certain, flash floods have become an expected phenomenon rather than a rare occurrence, due to rainfall intensity and the inadequate installation of drainage to hard standing areas.

The importance of removing surface water is becoming more and more imperative, by doing so you are helping to reduce the risks of erosion, degradation and pollution from animal wastes, nitrates, fertilisers and pesticides. Once contaminated this polluted surface water may then have no way of escaping during flash flooding when underground pipes eventually reach their full capacity and problems arise elsewhere in catchment areas such as rivers, sewers and streams.

Picture above : AquaCell Core (Blue units) Plastic, geocellular attenuation/ infiltration units, ideally suited for larger projects and/or projects that need to accommodate heavy traffic loading.

Although not yet compulsory, plans are in place to encourage preventative action to be taken. 'Run off water' tax is likely to be introduced in the near future in an attempt to encourage those who have not taken the adequate action to manage their surface water drainage, to do so. All hard standing areas will need satisfactory drainage measures installed whether they are new builds or existing structures. Those who do take action to improve surface water run off may benefit from tax concessions.

Specialist water engineers MJ Abbott Limited are aware of the importance and use of Sustainable Urban Drainage Systems (SUDS). SUDS is a sequence of management practices and control structures designed to drain surface water in a more sustainable fashion than some conventional techniques with the aim of reducing flooding and pollution and providing other additional environmental benefits.

Picture right : AquaCell Lite (Green units) Plastic, geocellular attenuation/infiltration units, ideally suited for landscape and non-trafficked applications.

Reducing and collecting excess water during wet periods for use in drier times is now an economically viable proposition in many situations. Two such methods are infiltration, which allows for surface water to soak away through infiltration systems offering 95% voids, and attenuation systems which consists of water storage capacity that holds excess surface water during periods of peak rainfall. These flexible systems are the physical element of SUDS and are designed and installed to take into account the quantity, flow rate and quality of dischargeable water by calculating the rainfall intensity in conjunction with the available hard standing surfaces available such as car parks and roofs of buildings.

The stored water is then gradually released in a controlled manner into the surface water drainage system or directly into watercourses, reducing the risk of flooding downstream.

Given that prevention is generally better than cure, then considering the merits of pre-empting possible future tax burdens by installing a system which prevents flooding and collects water for re-distribution or controlled release has to be a viable option, both economically and environmentally.

MJ Abbott has more than 40 years experience of water management on a diverse range of sites. For advice on dealing with drainage on your site or on selecting a SUDS system, please contact Nigel Pritchard on 01722 716361 or email nigel.pritchard@mjabbott.co.uk.

For further information please visit www.mjabbott.co.uk