If the specialist drainage team arriving at a site to make repairs find that they are unable to carry out this work because the pipes are irreparable, then in the past excavation was the next step of the maintenance process.
Nowadays, in this kind of situation, as well as when new water supply pipes or land drains need to be installed, the impact moling technique is used instead.
This is a form of trenchless technology where a pneumatic tool is used to create a hammering action and pierce through the soil instead of actually having to remove it.
The soil is compacted and displaced by the equipment and it can be employed as a really cost-effective solution for installing new pipes. Impact moling is user-friendly for the engineers conducting this kind of work and for the customer they benefit from a cheaper method of maintaining the drainage system.
The only situation where this might not be possible is when the soil condition is especially hard and rocks are present. Otherwise, this technology is put to good use and causes the minimum amount of disruption for the client and their property, making for a more environmentally-friendly way to install new pipes.