Yorkshire Water is investing £2.5m in Mapplewell, near Barnsley to reduce the number of discharges into the river Dearne from a storm overflow in the village.

Contractor Sapphire Utilities Solutions is constructing a new underground storage tank in private land off Carr Green Lane that will hold storm water during periods of heavy or prolonged rainfall.

The 12-metre deep, 557m3 tank will help capture significant stormwater flow from the overflow, reducing discharges, before returning the stored water into the sewer network to allow it to be treated. It is expected the work will reduce discharges from Carr Green by 80%.

Matthew Wilson-Wright, asset planning sponsor at Yorkshire Water, said:

“We are committed to reducing storm overflows across Yorkshire and are investing £180 million by April 2025 to tackle the issue and improve water quality in our rivers and at our coast. We considered a variety of options for this project and increasing storage was the only viable option to reduce discharges from the overflow at this time.

“The additional storage will hold stormwater during heavy or prolonged rainfall events, before returning it to the network and treatment works for full treatment once the rainfall event has passed. Ultimately, this will lead to a reduction in discharges to the river Dearne and help to improve water quality.”

The project is part of a £180 million investment project across Yorkshire by the end of April 2025 to reduce discharges from storm overflows. It follows a similar project on Dearne Hall Road, where Yorkshire Water is investing £2 million to construct 297m3 of additional storage in the sewer network to reduce discharges from that overflow by 81%.