The installation of new pipelines and sewers and the replacement and renovation of these structures without extensive surface excavation has been one of the major advances in engineering over the last ten years. Sophisticated items of machinery and instrumentation have been developed, and have been tried and tested in the most diverse and difficult ground conditions with tremendous success. Pipejacking and microtunnelling techniques offer considerable savings over conventional trenching methods and this, combined with the greatly reduced surface disturbance, is leading to an acceleration in...