A Wildlife Pond

LILAC cohousing, where I live, has a sustainable urban drainage system. This includes rainwater harvesting, permeable paths and a pond in the middle of the site. The pond performs 3 main functions:

• Flood attenuation: checking rainwater runoff from the site
• Amenity: providing a pleasant focal point in the communal gardens Promoting biodiversity: providing boggy and aquatic habitats and edges
• The frogs that inhabit the pond and its margins form part of the integrated pest management strategy for communal and private gardens on site.

Recently the pond liner has developed a leak. Consequently the pond is draining more quickly than it should. As a result, it dries out completely in long spells of dry weather. This has resulted in the loss of all the frogspawn in 2 out of the last 3 years. Some of the aquatic plants have also been seriously stressed.

Investigations into the location of the leak, and negotiations with the designers of the pond and the contractors who installed it are ongoing, and proving quite slow. The threat to the plants and animals may be ongoing for some time, so this design seeks to develop a contingency.

See this PDF design report for more details.