A major issue
Whilst the UK has experienced horrendous floods over the past couple of years, it has become a regular occurrence to hear in the news of scientific and agricultural research, which tells us that our earth is undergoing continuous climatic changes, resulting in unpredictable weather patterns. At the same time in a declining economy, we have further pressures to utilise every m2 of land that we own. Committing spaces previously used as the common front gardens into car ports or external entertaining environments. There is a danger of increasing the risks of localised flooding if we do not adapt the way we design and construct our landscape, using intelligent systems which permeate and filtrate the ground that we value so much.
“Land management activities over large geographical areas in the UK may appear to have minimal local impacts however there can be significant changes to freshwater ecosystems when aggregated as a whole. Similarly, in urban environments, the cumulative impact of seemingly insignificant alterations, such as non-permeable paving can have a tremendous aggregate effect on run-off.” Written by the Royal Geographical Society on The challenges of water policy in the UK.
“In October 2008 new legislation was introduced in England that requires all home owners to use a porous surface for their front driveway or apply for planning permission if they wish to use a non porous surface like tarmac. Therefore permeable paving has become a very important element in many sustainable urban drainage solutions (SUDS).” Broadcast by the BBC’s One Show, Permeable paving explained.
Hydrosmart
MBH offers a ‘greener’ pavement solution in its innovative product Hydrosmart. Providing permeable paving which replicates natural drainage patterns, encouraging water to cascade through the layered construction, whilst treating the pollutants and retaining structural integrity. The water captured can either be stored, released directly back into the water course or fed into a drainage system at a controlled rate of discharge. This system can significantly improve the quality of downstream habitats whilst actively reducing our reliance on local infrastructure during peak water levels.
The wearing surface of a permeable pavement should be formed with 210 x 105 x 65mm Hydrosmart™ permeable clay pavers manufactured in accordance with the requirements of BS EN 1344: 2003 at MBH PLC.
Hydrosmart has an attractive, durable surface which has excellent long term environmental and technical performance characteristics. Typically in rural areas only 5% of surface run-off is discharged into drainage systems, whilst in urban areas this figure can increase to as much as 95%. If installed on a mass scale throughout our cities, this system would have a significant impact to local infrastructure, ensuring that receiving local drainage networks are not running at full capacity.
Preferred solution
Where conditions allow, ‘infiltration’ pavements are the preferred solution, as surface water is captured within the system and does not enter drainage networks or water courses directly. Drainage systems are usually designed on the basis of a specific ‘design storm’ calculated through past data of storm return periods and durations. Rainfall levels vary throughout the country and therefore the location of the project is an important design parameter when specifying a permeable landscaping solution.
A ‘infiltration pavement’ allows rain water to trickle feed through the system and is filtered and cleansed by the various layers before dispersing into the ground.
A ‘tanked pavement’ is an impermeable flexible membrane which lines the pavement construction so that all falling water is temporarily captured within an underground reservoir. It can then be slowly discharged through a small diameter pipe at ‘green field run-off rates’ to a water course, an existing drainage network or a storage tank.
Permeable solution
MBH permeable pavement solutions require an accurate approach to the assessment of design loadings and the selection of construction materials. Aggregates are selected on the basis of their performance when fully exposed and in a saturated condition. It is for this reason that materials with a low fines content are required to ensure the stability of a pavement throughout its design life.
The first stage in designing this sustainable and durable product is the structural design process, followed by the selection of a pavement design section, related to a specific loading category.
Produced in MBH Blockleys factory, these wearing clay surfaces are manufactured in accordance with the requirements of BS EN 1344: 2003. Hydrosmart is provided in four distinct blends, Castleyard, Hadley Brindle, Hadley Red and Charcoal to give a variety of aesthetic choice, which retain colour without fading.
It is imperative that we design and specify permeable solutions into our living and working environments. It must aid our existing infrastructure during unpredictable weather and avoid the risks of flooding for our local communities. Hydrosmart can make a real impact to our natural vegetation, where a hard surface is required in close proximity to trees. This intuitive system allows water to percolate through infiltration and feed directly to roots, simultaneously working with the landscape. MBH are proud of this innovative, durable, aesthetically pleasing product, that has great longevity, ensuring it retains its function for future generations.
