Walthamstow Wetlands is Europe’s largest urban wetland. It is a fully operational water reservoir and the main source of water supply for 3.5 million people. On Friday 20 October 2017, the reservoir was opened to the wider public for the first time in 150 years. Over a period of three years, Polimekanos worked with Kinnear Landscape Architects, Witherford Watson Mann Architects and London Borough of Waltham Forest to develop the strategy, visual identity and design for wayfinding, interpretation and signage on the site.