Holywell Row, Suffolk

Flood Prevention

SDS stormwater storage system brings to an end years of flooding endured by villagers.

Overview

Holywell Row, a village near Mildenhall in Suffolk, has, despite its location in one of the driest and most water-stressed regions in the UK, experienced frequent flooding and sewage overflow for several years due to increasingly severe and unpredictable weather and limitations in the existing sewer network. With the area under growing pressure from planned housing developments, including 139 new homes in the village, SDS was appointed by Barhale, on behalf of the Anglian Water @one Alliance, to deliver a long-term drainage solution that would enhance the resilience of the local infrastructure and support future population growth.

What We Did

SDS designed and installed a Weholite HDPE attenuation tank in a field adjacent to the Holywell Row wastewater treatment works. The system consists of five interconnected rows of 45-metre-long, 1,500mm diameter pipes, each fitted with a manhole at the manifold end. With a storage capacity of 390,000 litres, the tank provides essential off-line retention of stormwater during periods of heavy rainfall. This approach alleviates pressure on the existing sewer network and enables controlled discharge to the water recycling centre once conditions allow.

Results

The installation has significantly reduced the risk of flooding by addressing the capacity constraints of the upstream Eldon Lane Pumping Station and diverting flows from the overburdened sewer system. The project enhances operational reliability during extreme weather events and helps to protect homes, public spaces and the environment. In addition, the use of low-carbon materials and the avoidance of constructing a new pumping station or lengthy pipeline has contributed to a capital carbon reduction of 81%, supporting Anglian Water’s wider sustainability and investment goals.

The flooding challenges at Holywell Row highlight the importance of investing in infrastructure that can adapt to modern demands. This project exemplifies Anglian Water’s commitment to resolving systemic issues, empowering communities and preparing for the future. By combining innovative engineering with community-focused initiatives, they are not just solving today’s problems but are laying the foundation for a resilient tomorrow.

– Xuan Li, Technical Manager – Water Recycling Infrastructure, Anglian Water @one Alliance

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