Drainage Services in Dorchester

Dorchester sits on chalk above the Frome valley, and the two halves of that geology behave very differently. On the higher chalk the ground drains freely and soakaways generally perform well, while the valley floor around Fordington and the water meadows carries a high seasonal water table that rises sharply after wet winters and pushes groundwater into any drain with open joints.

The historic centre, laid out on the Roman street grid, still relies on Victorian clay pipework at shallow depth beneath narrow streets and listed frontages, with mature trees along the Walks a recurring source of root ingress. Poundbury, by contrast, is entirely modern plastic drainage with separated foul and surface water and designed attenuation, so faults there are usually misuse or shared private runs rather than pipe failure. Outlying villages such as Puddletown and Winterbourne Abbas include a good number of properties on septic tanks and drainage fields governed by the General Binding Rules.

We start with a CCTV survey to establish pipe material, depth and whether groundwater infiltration is a factor, which is common on the valley floor and rare up on the chalk. Jetting clears root and silt blockages in the older clay runs, and no-dig lining suits the town centre where excavation under listed buildings is impractical. For rural properties we carry out percolation testing before specifying any new drainage field.