A defective sewer was located in a narrow alleyway between two rows of large houses in Bath. Very old and retaining walls were in place along the rear of one row of houses and the front of the other row of houses.
The sewer was backing up and needed to be cleared urgently while ensuring the existing structures were not damaged.
MDA undertook million-point cloud surveys of the existing retaining walls and set up survey monitoring points before the works commenced.
We also set up vibration monitoring at the base of each wall adjacent to the excavation of the access shaft.
MDA then excavated a 1.5m diameter shaft 5m deep by hand to avoid additional vibration for nearby structures and properties. The shaft was located down on top of the sewer repair which enabled it to be repaired, and provided a future access point, as this location had historic issues that re-occurred every few years.
MDA completed the works without incident and whilst maintaining minimal vibration and ensuring the local residents were satisfied that the works did not detrimentally affect their property.
The scheme was completely safely and on time meaning the Wessex Water customers were not without their foul water service.