Case study Stourhead

Over 1,000m2 of Formpave’s EcoGranite Aquasett paving has been used by the National Trust at its historic Stourhead estate to alleviate the risk of flooding in the large visitor reception area.

The National Trust’s Stourhead estate is a Palladian mansion set within 2,650-acres of parkland in Wiltshire. The partially-bound gravel surface at the large visitor reception area presented problems throughout the year including flooding, which was causing the existing gravel and topsoil surface to be washed away, exposing raised tree roots and creating potential trip hazards. A hard surfacing solution that was self-draining, accessible and aesthetically pleasing was needed.

Formpave offered the perfect solution, combining the environmental credentials of its EcoGranite paver, which contains up to 77 per cent recycled content, with the benefits of the SUDS and permeable paving system, Aquaflow.

The paving was installed in the visitor reception area, as well as the courtyard of the Spread Eagle Inn – an 18th century inn located in the village of Stourton, part of the Stourhead estate.

The visitor reception area had a number of sloping parts which meant that during heavy rainfall pools would form. Fortunately ground conditions were good, allowing Formpave to design the system to infiltrate back into the ground.

First, the surface needed to be levelled to ensure that the sub-formation was also level. This allowed ground storage to be maximised in the right places and minimised at the foot of the slope where capacity is naturally shallower and there is a greater tendency toward surface water.

By designing and installing the system in this way, Formpave was able to manage and eradicate flooding and pooling across the entire surface.

Following the success of the first installation, the team turned its attention to the courtyard of the Spread Eagle Inn where it faced the same on-site challenges as well as a number of well-established trees.

Trees have a ‘no-dig’ zone to protect the root ball. Paving directly up to the trunk would starve the roots of oxygen and water and cause the surface to become uneven and hazardous so the scheme was designed leaving a circle of exposed earth around the base of each tree.

It was important that the EcoGranite edging was seamless to the original 18th century cobbles and the paving was selected in ‘Victoria’, a warm, rustic cream colour ideal for the chalky tones of the downs.

Karl Papierz, National Trust’s project manager for Stourhead, said: “The Trust, as well as its partners and stakeholders have a vested interest in the entrance and courtyard areas as they have a direct impact on a number of businesses.

“All parties are extremely happy with the appearance and performance of the paving; it has eliminated the risk of potential flooding into the shops and inn, and has facilitated ease of movement around Stourhead. The rainwater run-off onto public highways has also been eradicated which in turn has eased erosion of the adjoining gravel pathways.”