Colin Gray writes:
OPAL, the Open Air Laboratories network is an exciting new initiative supported by The Big Lottery Fund. OPAL is encouraging people to get back in touch with nature. A wide range of projects is planned. The first survey that encouraged anyone with an interest in nature to participate, in February 2009, asked people to survey the variety of earthworms that could be found close to their homes, in the garden, local park or nature reserve.
An OPAL sponsored nation-wide survey started in November 2008 by University College London is looking at lakes and ponds in the UK and Fleet Pond was chosen as representative of lakes in the South East. Water quality, level of siltation, fish species and chemical analysis are all being studied.
OPAL has produced a bathymetric survey of Fleet Pond which depicts water depths in graphic form (see picture above). This shows very clearly just how serious the silt situation has become. Nowhere over the 52 acres (21 hectares) is the depth more than 0.82 metres. Large areas are less than 0.5 metres. Work to address this situation is urgent if we are not to lose over a third of the pond and to put the nature reserve at risk of losing SSSI notification.