Segmental Shaft Sinking Projects

Donegan Civil Engineering delivers complex shaft sinking projects across the UK, using both caisson and underpinning techniques depending on site constraints and ground conditions. We construct shafts from 1.5m to over 25.0m internal diameter, and our in-house teams bring decades of experience in both open-cut and deep excavation environments.

With a large fleet of specialist shaft sinking equipment and extensive experience working in challenging conditions — including saturated sands, urban areas, and confined sites — we’re trusted by major water authorities and contractors to deliver safe, efficient shaft construction.

Contact our friendly team today to discuss more about our shaft sinking projects!

Our Work

Caisson Shaft Sinking

Jacked caissons are particularly effective in poor ground such as running sands or high-water tables. Our teams install prefabricated concrete rings as the shaft is progressively jacked into place, providing immediate support and excellent control over settlement and groundwater ingress.

Underpinned Shaft Sinking

For larger diameter shafts — typically in excess of 20.0m internal diameter — underpinning remains the preferred method, provided ground conditions are favourable. This technique is especially suited to firm, dry clays and competent rock strata where excavation can proceed safely in staged rings beneath the shaft lining.

Donegan Civil Engineering has delivered numerous large-scale shafts using the underpinning method, often in confined or heavily serviced urban environments. Our experienced teams manage every stage of construction, from excavation and ring installation to ventilation, dewatering and safe working access.

We also work closely with clients and designers to integrate temporary works solutions, and where required, we can provide in-house engineering input to optimise construction sequencing and mitigate ground movement risks.

We own a large range of specialist plant and equipment, and have a vastly experienced workforce and management team to deal with any form of shaft construction required.