SCRAYINGHAM ECOLOGICAL WASTE WATER TREATMENT SYSTEM, NORTH YORKSHIRE EC regulatory changes mean that there is now a need for sewagetreatment plants at many isolated communities where previously cesspits sufficed. At Scrayingham, Yorkshire Water has taken an innovative approach, largely thanks to the enthusiasm of a local landowner who provided the site for an ecological treatment system.
This is a pond stabilisation arrangement which is believed to be the first in the UK to take combined flows. It now treats the sewage effluent for a hamlet with a population of about 100 in 40 houses.
Raw sewage runs by natural fall in the ground about 250m from the village to the first pond and then via a 100mm rock filter to a series of five small ponds interconnected by 40mm rock filters.
Clean effluent runs further downhill to the River Derwent. The intention is to create a wildlife habitat so that waste is digested naturally without the need for external power or chemical treatment.
Wetland plants have been selected to introduce oxygen to the ponds, which are surrounded by a mix of grasses and wildflowers intended to minimise the need for maintenance. At a capital cost of more than £5,000 per head, Scrayingham's sewage works is not cheap. But it is a pioneering scheme and, if it fulfils its promise of low maintenance, it may not be excessively extravagant.
To recognise a project which demonstrates a particular contribution to environmental issues or in which environmental issues were a key factor in the concept and/or execution. Sponsored by Atkins THE TEAM Client Yorkshire Water Services Cost £575,000 Principal designer Iris Water & Design Contractor GMY Winn & Co Other firms Charles Haswell & Partners;