he built environment has grown rapidly over the last 50 years while the UK’s weather has deteriorated, resulting in a 50% increase in consecutive rainfall days. This has all contributed to a growing problem of flooding or excess standing water, especially in areas of urban development.
With no ‘one-size-fits-all’ solution, there has been a surge of policy and legislative guidelines introduced to help shape the development process, as well as many products available to provide solutions that fit whatever environment an architect may be working with.
For new-builds, whether residential or commercial, a clear SuDs vision at the beginning of the design process can exploit the site’s opportunities, troubleshoot what restrictions or limitations may be imposed from a planning perspective and indicate how the design and SuDs requirements may marry to ultimately deliver on the developer’s aspirations.
For designers, understanding the policy requirements, as well as the maintenance and management considerations, will have a significant effect on the viability and cost-effectiveness of the particular SuDS used and the benefits it brings to the overall project. Good urban design is only possible where the design and management of water in a scheme is integrated as an important part of the whole concept, and there are various products – from paving to retaining walls – which can be incorporated to achieve the design vision effectively.
Setting the design criteria at the start of the project and establishing a clear SuDS vision will ensure the SuDS components are not secondary to other requirements for the site, but instead incorporated from the earliest inception.
Take the recent catastrophic floods seen across the north of England and South West of the country, for example. It was suggested by the Environment Agency that in many cases the flooding has been caused, not by swollen rivers as initially presumed, but by the runoff from paving, highlighting the very real consequences of giving SuDS a secondary thought. Permeable block paving can be an essential solution for build projects which require suitable drainage solutions.
A shining example
A major leisure complex was one of the first of its kind in Northern Ireland to incorporate AG’s Xflo Plaza permeable block paving system, which achieved the architect’s vision and created an effective system for drainage without compromising on aesthetics.
Newry and Mourne District Council specified the new facility must provide accessibility and functionality with a modern, high-spec interior that would encapsulate the overall ambitious future vision for the town, enhancing yet complementing the existing town centre for residents and visitors. Critical to the project was a sustainability aspect, with solar thermal panels being introduced to heat the water, a heat recovery system installed and a UV pool treatment plant as well as rainwater harvesting elements incorporated.
Permeable block paving would be an essential component in achieving the dual objectives of accessibility and functionality, offering suitable levels of drainage for this urban town centre location. The system provides the functional permeability performance required in a sustainable urban drainage system, designed to mimic the natural movement of stormwater and replace conventional stormwater drainage systems. All of the block systems have been designed to allow an initial surface infiltration in the order of 2000 litres/sec/ha. Surface water flows through the joints and is absorbed into the underlying voided sub-base where the water is treated, stored and slowly released into the ground (infiltration) or the surface water drainage system (attenuation). The enlarged spacers on the sides of the block create 7mm-wide joints, which allow surface water to pass through the paving.
The product’s granite aggregates provide strength and durability – key for this complex structure situated in the heart of Newry city, attracting high levels of visitor footfall and required to stand the test of time. Used in ‘Salt’ and ‘Pepper’, the colours were hand-selected to enhance the urban look of the leisure centre complex, all while offering certain natural qualities that would blend with the green playing fields it was situated near. The textured washed surface gives the appearance of natural granite stone but with the quality assurance of concrete block paving.
AG has introduced eight stunning new colours to its popular range of Plaza paving taking the range to a total of 11 colour blends. The unique-to-market, new range is infused with hints of natural coloured aggregates, each delivering a striking visual effect. The Nordic-inspired colour palette draws on spices, plants and flowers to offer ones such as Lavandel, Paprika and Kanel. AG’s Plaza paving has a surface formed from natural granite aggregates and is colourfast and durable. The new additions have been introduced to give architects huge choice while still offering Plaza’s vibrant aesthetic appeal, colourfastness and strong durability. All colours are available in a variety of intensities, depths and formats, including AG’s Xflo permeable paving system.
