Duddon: Main Issues

Water Quality

• The River Duddon has natural background acidification from geological mineralisations.
• Coniferous plantation and clear felling practices also contribute to low pH spikes.
• pH values as low as 3.7 have been recorded: values as low as this have been shown to lethal to salmonid fish.
• Widespread pollution known as diffuse pollution is an issue across the catchment. This is causing a decline in dissolved oxygen concentrations which are important for all stages of river life.
• Only a small area in the catchment is connected to mains sewerage, meaning the is a large number of septic tanks (or even no formal sewerage at all) leading to issues with appropriate maintenance and the associated problems with diffuse pollution to the local becks.
• Pollution can include increased levels of fertilisers (which are nutrient rich) and pesticides as well as excess sediment.

Water Flow

• The Duddon Valley is the principal aquifer in the Barrow-in-Furness area, including the River Duddon itself, Harlock Reservoir and Poaka Beck reservoirs which are all used as public water supplies.
• Mitigation measures are required to provide compensation flow to protect and improve water quality.

For more information please take a look at our catchment maps.