Wet ground, a high water table and a required fall that left almost no margin over the run. The kind of job where the method is decided before anyone digs.

Shoring, not judgement

Everything beyond 1.30 m was shored. That is not a call the crew makes on the day based on how the trench looks — depth, soil type and surcharge decide it, and the shoring is delivered with the pipe so it is never the thing that slows the sequence down.

Falls are not negotiable

Invert levels were set and checked at every junction, then re-checked after bedding, because pipe moves when you compact around it. On a run this long with this little margin, a single settled section would have flattened the fall and put the whole main at risk.

Tested open

Every section was air-tested with the trench still open and the result recorded against the as-built. Nothing was closed on trust. At handover, zero failures — which is the only acceptable number, since finding one after backfill costs ten times what it costs to find before.