Yorkshire Water is improving the performance of two storm overflows in York that discharge into watercourses in the city during periods of prolonged or heavy rainfall.

The two projects, totalling a £170,000 investment, will focus on the overflow under the Boots store on Coney Street, which discharges to the Ouse, and the Fishergate overflow on Fishergate, which discharges into the Foss.

A significant proportion of overflows at the two sites are caused by water from the rivers entering the sewer network following heavy or prolonged rain in the area.

Modelling indicates the work could half discharges from the Coney Street overflow and reduce overflows by approximately 10% at Fishergate.

The work is part of a two-year £180 million investment by Yorkshire Water to reduce discharges into watercourses across Yorkshire. The utility’s AMP8 business plan outlines a further £1.4 billion investment in the reduction of overflows between 2025 and 2030.

Martin Ineson, project manager at Yorkshire Water, said:

“We have committed to reducing discharges into watercourses across the region, as we know it is an issue that is important to our customers.

“In York, many of the discharges are due to the river flowing into the sewer network, as we experienced in recent weeks, following a prolonged period of heavy rain. The work we are carrying out on Coney Street and Fishergate will limit these instances and reduce overflows into both the Foss and Ouse. As well as these projects, we are planning more investment in York’s overflows in the next two years and beyond to further reduce discharges.”

Work on the two sites will include:

Altering the operation of the Coney Street overflow, meaning greater flows of wastewater would be required before overflows occur.

Upgrades to stop the river inundating the sewer and to prevent blockages, which can also cause an increase in discharges to the watercourse from Fishergate.