Winchester dew pond Lullington Heath pond liner renewal

Tender description

Project Summary Chalk heath covers just under a third of the Reserve. Elsewhere, bushes, chalk grassland and valley grassland form a patchwork across the site. Over 250 types of plant grow here. More than 98 types of bird have been seen, 50 of which nest on the Reserve, and 34 butterflies are listed amongst the hundreds of types of insects known to be present. Badgers and foxes do well on the Reserve, as do other small mammals such as rabbit, stoat, weasel and several types of mice, vole and shrew. Sheep grazing remained as the dominant type of farming on the Downs for over a thousand years allowing herb-rich grasslands and chalk heath to develop. Grazing continued until around the Second World War. Thereafter, grazing was stopped to prevent pollution of water which is drawn from the chalk beneath the site for public consumption. Chalk heath once covered 40 hectares at this site but the onset of Myxomatosis in the 1950's virtually destroyed the rabbit population which had previously maintained the heath, and scrub consequently gained a firm hold. Now the areas of chalk heath are restricted to wide mown rides and grazed paddocks. The ban on livestock grazing was lifted in the 1970s but by this time scrub had invaded all areas of the Reserve except those kept clear by mowing. Since then, we have been extending the open areas by grazing, mowing and scrub clearance so that the traditional short turf, rich in plants and animals, can be re-established. Winchesters dew pond is a significant feature of this site from a social, environmental and habitat point of view. It holds many aquatic species of flora and fauna including Great Crested Newts (Protected species). This pond has been known to dry out in some dry summer periods, it is only fed via direct rainfall and its location is not favourable for wider water catchment. Generally, the winter rainfall is sufficient to ensure it stays wet for the important summer breeding / flowering period. It has been noted that the last year despite heavy winter rainfall, the pond was not retaining water. Following investigation, it has been concluded the liner is no longer watertight and full replacement is required. Work to be undertaken Removal of clay capping material, remove liner, profiling existing area, replace underlay and liner, cover liner with new clay capping and add suitable plants (when water level sufficient).