Yorkshire Water has admitted a £1.5m scheme to reduce storm overflow discharges into a North Yorkshire river has not performed as expected.
When the investment was announced in 2024 for the River Ure in Ripon, the water company said the scheme would reduce the issue by about 75%.
But it said the number of recorded discharges from its Clock Tower combined sewer overflow (CSO), near the Ripon by-pass bridge, fell from 75 in 2021 to 43 in 2025, a reduction of about 43%.
The company has described the result as “disappointing”, but stressed that comparing individual years was complicated by rainfall levels.
“[2025] was a particularly dry year, which will have further contributed to a decrease in discharges,” a Yorkshire Water spokesperson said.
“As such, whilst there has been a reduction, the scheme did not perform as expected, which is disappointing.”
Combined sewer overflows are designed as pressure-relief points on sewer networks which carry both wastewater and rainwater.
During heavy rainfall, they can discharge into watercourses to prevent overloaded sewers backing up into homes, businesses and streets.
Such discharges can be permitted by the Environment Agency under specified circumstances.
