ECOSA were commissioned by City of London Corporation to carry out an ecological assessment of Hampstead Heath in 2013. Hampstead Heath is the largest area of open space in north-west London. The Heath comprises a varied landscape of woodlands, grasslands and veteran trees, the site forming a significant green space visited by over 7 million visitors per year. There are four chains of ponds at the site. To the south are the Hampstead and Highgate valleys that have been dammed to create the Hampstead and Highgate ponds, both valleys eventually joining to feed the River Fleet. To the north there is the Golders Hill Park chain which has been impounded at the lower end to create ponds in the designed landscape of the former Golders Hill mansion, and the Heath Extension chain. Both eventually join the River Brent.
The City of London Corporation has an obligation to maintain Hampstead Heath for recreational purposes in its preferred natural state. Within their 2007-2017 Hampstead Heath Management Plan, the Corporation's committees identified various environmental improvement objectives covering a wide range of ecological issues. As part of this, the City of London Corporation intended to enhance the conservation value of the Heath's ponds, as well as improving flood management and water quality at the site.
Plans for the Hampstead Heath Flood and Water Quality Management Works were prepared in consultation with English Heritage. To inform their production, a detailed programme of surveys was required to develop a comprehensive hydrological management strategy. As part of this, it was deemed necessary to carry out a range of ecological surveys.
ECOSA carried out Phase 1 and further bat, great crested newt and invertebrate surveys at the site. Recommendations included consideration of timescales of works in relation to protected species, and allowing 'safe refuges' by way of reed planting in the larger lakes to increase the overall value of the waterbodies for a range of wildlife, including birds, invertebrates and amphibians.
In addition, ECOSA were commissioned to review all historical records of invertebrates at the site. These surveys assessed the ecological importance of the various areas of the site and allowed the development of a detailed mitigation and enhancement strategy.
Visitors continue to enjoy Hampstead Heath's remarkable range of natural habitats and facilities.