Sydney Water identified a number of stormwater assets in the City Area 29 and Blackwattle Bay stormwater catchments which required rehabilitation as they were old and prone to leakage. Insituform Pacific Pty Ltd were successful in their bid for the contract and engaged EMM to provide environmental services for the work.
The rehabilitation works generally involved the following:
- Removal and offsite disposal of existing debris and silt to enable further investigation of stormwater pipes
- Full CCTV investigations, and pipeline profiling as required
- Modification of upper sections of the maintenance holes for improved access
- Installation of ‘cured-in-place pipe’ linings to specified lengths
- Full or partial length dig and replacements of some stormwater pipes
- Brick oviform reinstatement repairs to Pitt St and Cleveland St stormwater channels
- Construction of some new maintenance holes
- Site restoration
The works were frequently in environmentally sensitive areas, particularly areas with heritage constraints. For example, a number of sites were in The Rocks, which is a heritage conservation area which also contains many individual heritage items. The works also involved rehabilitation of heritage listed stormwater pipes such as the Bennelong Stormwater Channel.
Each site required a construction environmental management plan (CEMP) to be prepared prior to works commencing. EMM is preparing the CEMPs for the work, which involves site inspections by our archaeologists and environmental scientists and preparation of the CEMPs and heritage approvals.
Many of the CEMPs have been approved by Sydney Water and some rehabilitation works have commenced.