Groundworks in Wellingborough are where the valley position stops being a description and becomes a cost.
On lower lying plots an excavation can take water, and a trench with water in it is a different job from a dry one. It may need pumping. It may need supporting sooner and more thoroughly. The concrete may need to go in promptly rather than when it suits the programme, and there are weeks in the winter when the honest answer is that the ground is not fit to open. None of that is unusual in a river valley and all of it belongs in a quotation rather than in a variation.
Bearing is the other question. Ground near a river includes alluvial deposits that can be soft and variable over short distances, and a foundation designed off an assumption rather than off a hole can be adequate at one end of a trench and not the other. We dig to find bearing rather than to reach a figure on a drawing, and the building inspector will want to see the same.
That is why the trial hole here is the single most useful hour on a project. It answers the water question and the bearing question together, and it turns the two largest variables in a groundworks price into known quantities.
Everything is inspected before it is covered. We book the inspections and we do not pour over an unseen trench. Our footings and excavation page explains our approach.