A higher standard of wastewater treatment in the UK has been linked to substantial improvements in a river’s biodiversity over the past 30 years, ensuring a welcome success story for wildlife, say scientists.
The Centre for Ecology & Hydrology analysed data from the regular monitoring of both chemicals and invertebrates in the River Ray in Wiltshire by the Environment Agency and its predecessors between 1977 and 2016. This Thames tributary is downstream from Swindon’s large wastewater treatment plant.
The Defra-funded study found that, since 1991, there has been a steady increase in both the diversity and abundance of freshwater invertebrates, which play a vital and varied role in an ecosystem’s food chain. The water is cleaner due to a reduction in ammonia (a chemical present in human sewage that is potentially toxic to animals) plus an increase in oxygen levels (as a result of less organic matter being discharged into the river).
Read more at: University of Cambridge
The River Ray in Wiltshire is downstream from Swindon's large wastewater treatment plant. (Photo Credit: CEH)