Waterway excavation and ground assumptions
The Challenge
Hydropower tunnels, intakes and penstocks can encounter ground or groundwater conditions that change support, excavation and lining requirements. A quantity change and a change in excavation method have different commercial effects.
Our approach
We compare the contract's ground information with the geological records and the engineer's instructions. Extra excavated volume, a different support requirement and reduced advance are assessed separately: they need different evidence and may receive different treatment under the contract. That separation also helps avoid charging the same resource through a revised excavation rate and a delay claim.