With new legislation set to increase the use of Sustainable Urban Drainage Systems (SuDS), John Lloyd, head of design at Hanson Formpave, looks at the benefits SuDS offer and why builders’ merchants should be prepared.
The Environment Agency estimates that more than 5m people in England and Wales now live or work in properties that are at risk of flooding – a number that is set to quadruple over the next 20 years as our climate becomes prone to intense rainfall.
Large areas of hard landscaping can add to the problem but this need not necessarily be the case. Hanson Formpave offers a range of permeable paving products for paths, driveways and patios that aid run-off. Many can also be combined with its Aquaflow Sustainable Urban Drainage System (SuDS) to provide complete surface water management.
SuDS can reduce the risk of flooding and help control the amount of water that enters the drainage infrastructure but its use has not yet been made mandatory. This is potentially set to change this year as the new legislation, as part of The Flood and Water Management Act 2010, comes into force. It applies to all new schemes requiring planning permission and will compel builders and developers to consider SuDS at the earliest stage of a project’s development.
Under the previous legislation everyone had a right to connect their drains to sewers; this Act removes this right and approval will be required before a connection can be made.
If a builder decides that they don’t want to install a SuDS they will have to justify their decision. The cost to disprove it, particularly for small developments, is likely to be more than implementing the system in the first place. And, if you’re already creating paths and driveways, why not put the space to good use?
Many builders are already considering SuDS in their developments to meet conditions of planning and tackle drainage issues while providing an attractive finish.
The concept behind SuDS is to use cost-effective solutions with low environmental impact to drain surface water run-off in a controlled way, replicating nature. This is done through collection, storage and cleaning of the water before it is slowly released, either into the watercourses or directly into the ground.
Cheaper in the long run
Developers may think that adopting SuDS will cost them money but, when designed well, they can prove to be much cheaper than underground water storage tanks. In addition, project lead times are reduced as pipework, tanks and sewerage approval aren’t required, automatically removing the associated installation time, labour and costs – and counteracting any additional monies spent on the paving and SuDS materials.
The Aquaflow system, for example, allows water to drain through the permeable paving blocks and upper filter layer, which cleans the water, before it is stored within the sub base for release back into the environment or harvested for flushing toilets, washing cars and watering soft landscaping.
It is also cost-effective as it requires far less excavation – more than 300mm less – than some other systems, providing cost savings in labour and waste removal as well as wider environmental benefits.
Most of the paving range can be incorporated with the Aquaflow SuDS, and among its portfolio of paving products is EcoGranite, which is manufactured using up to 77% recycled content. It is cheaper than natural granite but matches its performance and appearance and can be used with the Aquaflow system to create a sustainable paving solution.
All products in the Formpave range are ISO14001 accredited and certified with the BES 6001 Responsible Sourcing of Materials Standard, recognising their environmental credentials.
To help merchants, Formpave also has a comprehensive brochure available which includes the full product range and answers the questions routinely asked by retail and commercial contractors. It also has clear instructions on laying block paved driveways, patios or paths as well as cleaning and maintenance tips.
There is also a free design service to help builders prepare draft proposals or validate a client’s own designs. All plans that have been provided or approved by Hanson Formpave are covered by professional indemnity insurance.