Another strategy that is becoming more prevalent is the greening of roofs for institutional buildings. As lighter plantings become more available, existing public buildings can realistically contribute to a comprehensive water management strategy by installing green roofs, on a wide range of buildings from the podium of the major arts centre, to offices for civil servants, to large commercial buildings, private and public. Linked to the water strategy would be the use of more ecologically appropriate porous surfaces in the areas used for festivals, as well as use of conifer trees planted to create sonic screening. Another facet of the proposal was a Lighting Strategy inspired by the visual character of many distinctive existing marquees. The Collective favoured ecological lighting strategies, including directing lighting towards the ground or towards reflective materials, intensifying luminous effects, and the use of  phosphorescence.