Permeable Paving and Street Trees in Harmony

A new case study highlights the impact of concrete block permeable paving as an irrigation source, sustaining street trees and green infrastructure. The award-winning Bridget Joyce Square in Australia Road, White City, London, is a sustainable drainage (SuDS) park with community at its heart and an exemplar for future urban landscapes. The scheme won ‘Winner of Winners’ (the President’s Award) as well as Winner of the ‘Adding Value through Landscape’ category at the 2017 Landscape Institute Awards, and also an ICE London Civil Engineering Award 2016.

Its low-intervention, thin overlay technology enables sustainable reuse of conventional road bases and their embodied carbon, creating attractive, safe, shared-surfaces. Capturing rainwater runoff straight from the surface without gulleys, the permeable paving overlays provide a gradual flow of clean water laterally into raingardens or basins, for storage and irrigation. Interpave revisited the project in August 2021, around 5 years after completion, and noted that the permeable paving was performing well and the trees and other green infrastructure were healthy, substantial and particularly well-established.

This project has important implications for the delivery of measures to address climate change. The 2021 ‘National Planning Policy Framework’ (NPPF) states: ‘Planning policies and decisions should ensure that new streets are tree-lined and that opportunities are taken to incorporate trees elsewhere in developments…[and]… appropriate measures are in place to secure the long-term maintenance of newly-planted trees, and that existing trees are retained wherever possible’.

Concrete block permeable paving offers unique opportunities to collect, store and treat rainwater runoff, removing pollutants before irrigating green infrastructure. Local planning authorities now need to incorporate long-term tree maintenance measures in their planning consents and, as a straightforward spatial measure, permeable paving providing irrigation, offers a sustainable multifunctional solution.

Download the case study here.