We are proud to announce a significant milestone at Havant Thicket Reservoir, as works have now progressed above natural ground level for the first time.
This achievement marks the successful completion of the ground improvement phase, an essential stage in preparing the reservoir for long-term stability and performance. During this phase, the site was carefully lowered by approximately two metres before being rebuilt, layer by layer, back up to natural ground level.
While the transformation may appear modest from the surface, the scale and precision of work required to reach this point has been substantial. Key achievements during this phase include:
- Over 1.5 million tonnes of clay placed in engineered layers, each typically 150–200mm thick
- Every layer compacted through multiple roller passes to meet rigorous engineering standards
- Approximately 75,000 truckloads of material transported, placed, and managed across the site
- Installation of around 160,000 tonnes of sand to support the ground improvement process
With this phase now complete, construction continues above ground using the same meticulous methodology. Material will be placed and compacted in carefully controlled layers, gradually building the structure to form a safe, durable reservoir embankment designed to stand the test of time.
Reaching this milestone is a testament to the skill, dedication, and consistency of the teams working on site day in, day out. Their commitment ensures that every layer meets the high standards required for a project of this scale and importance.
As part of Portsmouth Water’s Havant Thicket Reservoir project, this progress represents an exciting step forward in delivering a vital piece of infrastructure that will support water resilience for the region for generations to come.