Emergency Repair and Relining

Project Summary Sheet

Customer: Coliban Water

Location: McIntosh Street, Echuca VIC

Delivered: December 2016

The Challenge

Large voids were appearing in the narrow access path between two houses. The voids were potentially undermining the foundations of both.

Internal CCTV inspection showed that a section of the sewer running between both houses had collapsed. The sewer was six metres deep. Roots were entering from other cracked and leaking joints
along the line.

Repairs needed to be completed without risk to the structure of these houses.

The Solution

Interflow proposed excavating and replacing the damaged section, then installing a structural SPR™ EX – Expanda Pipe liner to renew the full length of the rest of the sewer.

A methodology was developed that allowed for working without damaging house foundations.

The Project

Extensive root removal from the sewer was necessary before internal CCTV inspection could be carried out. Once CCTV had identified the location of the collapsed section, it was exposed using hydroexcavation
and hand digging. Timber shoring was installed to ensure the excavation did not collapse. The collapsed section of sewer was replaced with UPVC sewer pipe and embedded in stabilised sand.

The entire sewer was then lined with SPR™ EX – Expanda Pipe liner, installed from existing maintenance holes.

Site restoration included backfilling of the excavation with a pumped cement stabilised slurry with the timber shoring left in-situ.

A feature survey was conducted on the houses to ensure there was no movement/ sinking during the works.

Conclusion

The project was successfully completed without incident in these complex and sensitive conditions. The temperatures during this period were in the mid-thirties and the work was arduous.

Interflow’s crew was complimented for the commitment they showed in carrying out the works safely and efficiently, with exceptional consideration to the householders who were affected.