These are the areas of Derbyshire with the most polluted rivers and waterways – with sewage being discharged across the county

Sewage discharges are the release of raw, untreated sewage into rivers and other bodies of water. These discharges often take place through the operation of storm overflow valves. These are designed to release water from the sewer network when the volume of water is too great for it, for example due to heavy rainfall.

Some use of storm overflows is permitted, to avoid the sewer network becoming overwhelmed and risk sewage backing up into homes and businesses. However, environmental campaigners have alleged that many water companies are using storm overflows more regularly than they ought to.

Data published in June, for 2024, from the Environment Agency has shown the areas across Derbyshire where sewage discharges occur most frequently – and the full list can be found below.