Throsby Creek Rehabilitation

Client - Hunter Water Corporation, NSW

Total Project Value - $1 Million

Project Overview and Scope

Hunter H2O was engaged by Hunter Water to manage the rehabilitation of approximately 800m of lower Throsby Creek between Maryville and Tighes Hill.

Throsby Creek was channelized in 1930. Much of the non‐tidal channel through Islington and Mayfield was constructed using concrete wall and base slabs which proved to be quite robust. The tidal sections of the creek (typically east of Maitland Road) retained its natural base while the walls were heavily reinforced with sandstone armoring. Much of the sandstone had either succumb to erosion or undermining resulting in undesirable bank erosion and mangrove reestablishment.

Following the June 2007 super‐storm, the community opinion was polarised, many welcoming the aesthetic benefit of the naturally reestablished mangroves, and many concerned with mangrove odour and hydraulic impacts on the stormwater system.

Key Success Factors

HH2O was involved in extensive community consultation including several community workshop during the planning/design aimed at both informing the community about upcoming works and seeking community input on the final design.

The final design encouraged re‐establishment of the aesthetically pleasing mangroves in locations where hydraulics where not critical whilst limiting the potential for re‐establishment in higher velocity areas. This outcome pleased most community stakeholders and helped environmental planning activities proceed without major disruption.

One of Hunter Waters’ key objectives was to maximise the extent of rehabilitation that could be achieved with a limited capital budget. HH2O worked closely with the construction contractor on a ‘unit rate’ basis amending the design and maximising reuse throughout the project. Following completion of the original scope (approximately 500m) sufficient budget existed to rehabilitate a further 2 sections of bank yielding almost twice the originally anticipated rehabilitation length.

Much of the reclaimed and unused sandstone blocks were donated to NCC for reuses in future community projects.

Enter your Hunter H2O Holdings Pty Limited username.
Enter the password that accompanies your username.
To prevent automated spam submissions leave this field empty.