Palladian Bridge, Prior Park Landscape Gardens, Ralph Allen Drive, Lyncombe

This application proposes repairs to the Grade I mid-18th century Palladian Bridge which forms part of the designed landscape of the Grade I Prior Park within the Bath conservation area and World Heritage Site. The bridge is based on Palladio’s original, refused design for the Rialto Bridge in Venice and was built by Richard Jones as part of landscaping works to extend the gardens to the north by Capability Brown. The garden forms the wider landscape setting of the Grade I early to mid-18th century Prior Park mansion, now Prior Park College. The bridge forms a critical landmark viewpoint due to its centralised position in long-range views from the north and south and visually emphasises the architectural relationship and intentional similarity in design between the bridge and the mansion house across the sloping parkland. Historic England identifies the bridge as a very rare feature, being only one of four of its kind in the world.

The Trust is supportive of the principle for conservation works and remedial repairs to the structure to ensure its continued material health and aesthetic and architectural integrity.

However, we have some concerns regarding aspects of the proposed works as raised in the Condition Report:

We query the proposed extensive use of epoxy resin to reset balusters and copings. We note this material’s benefits as structurally hard-wearing and often water resistant, but we note that its selection over more traditional, permeable, and more easily reversible methods has not been elaborated as part of this application. We suggest that this aspect of proposals is further clarified through the submission of details, with regards to the ease of future repair works to the bridge (with possible disassembly/stone replacement) and retaining the breathable qualities of the stone.

We additionally highlight the proposed use of a lime putty mortar with a “pozzolanic additive… such as Agrical”. Pozzolanic additives are typically used to speed up the carbonation process and achieve a hydraulic lime performance in damp or frosty conditions, although the specific qualities of Agrical (as referenced) are unclear. We therefore suggest that further details are submitted regarding the use of an additive to the mortar and the specific additive choice; we maintain that the proposed strength of the mortar should complement the softness of Bath stone and the bridge’s fine detailing and jointing.