Uffculme Wastewater Treatment Works Storm Storage Scheme | Ground Investigation

The LK Group was appointed by Galliford Try to undertake a detailed site investigation in support of South West Water’s storm storage improvement project at Uffculme Wastewater Treatment Works (WwTW) in Devon.

The scheme formed part of a wider investment programme aimed at reducing storm overflow events, improving environmental performance, and enhancing the resilience of wastewater infrastructure. Located within a constrained semi-rural site, the project required a comprehensive understanding of ground conditions and existing infrastructure to inform the design and construction approach. 

Our investigation programme was designed to assess the geological and geotechnical characteristics of the site, establish groundwater conditions, and identify the location and condition of existing buried services. Working closely with Galliford Try, The LK Group delivered a combination of intrusive ground investigation techniques and service detection surveys to provide accurate, reliable data for the project’s optioneering and design phases. 

The findings identified challenging ground conditions and a dense network of buried services across the proposed construction area. This critical information enabled the project team to assess the risks associated with various storm storage solutions and informed key design decisions at an early stage. 

The site investigation played a significant role in eliminating higher-risk options, including a traditional in-ground storage shaft and an above-ground reinforced concrete extension. The data collected ultimately supported the selection of an above-ground stainless steel storm storage tank, which offered a reduced construction footprint, lower excavation requirements, and minimised disruption to the operational treatment works. 

By providing robust geotechnical and utility information, LK Group helped Galliford Try reduce construction risks, improve programme certainty, and develop a solution that met South West Water’s environmental objectives. The successful delivery of the site investigation ensured the project progressed with confidence while supporting long-term improvements to stormwater management and river water quality in the local area.