improvements relating to inspection wells for drains and sewers.

摘要

. A prefabricated drainage inspection chamber formed from plastics material has a base and at least separately formed side wall sections. The base has a maximum external dimensioning such that it can be stowed within the adjacent side wall section and the latter side wall section has a maximum external dimensioning such that it can be stowed within the next upper side wall section. The two side wall sections in the assembled condition of the drainage inspection chamber are located vertically relatively to one another by projections on one of the side wall sections locating between ribs formed on the other side wall section.