Consultancies
Site Investigations and Design
The Dams and Civil group of the NSW Department of Commerce are undertaking this consultancy, which includes geological, geotechnical, seismology and hydrology investigations. Dams and Civil bring a wealth of experience to the Tillegra Dam Project. They have extensive expertise in the design of new dams, the upgrade of existing dams and reviewing the safety standard of existing dams.
The first task for Dams and Civil has been to review all the previous studies relating to the dam proposal, plan the next level of geotechnical testing and undertake those investigations along with earthquake risk and flood studies. These studies will allow options for the type of dam wall and arrangement of the spillway to be considered and will be independently reviewed.
After a preferred option for the dam wall has been selected, Dams and Civil will undertake more specific geotechnical testing to develop the concept design of the dam and its numerous components.
The concept design will be reviewed by an independent panel of experts comprising five members, each of whom is recognised internationally as an authority in his respective field. Further details on the review panel are available in the September 2007 issue of The News about Tillegra Dam. The concept design will also be submitted to the NSW Dams Safety Committee.
Dams & Civil will then proceed to the detail design phase which will fully define the work sufficiently for construction and will again involve reviews by the independent panel of experts and submission to the NSW Dams Safety Committee.
Environmental Assessment and Planning
Connell Wagner are undertaking this consultancy. Connell Wagner have a strong record of providing planning, surveying, engineering, scientific and environmental project management services on major infrastructure projects in the energy, water, telecommunications, defence, transportation and urban development sectors.
The first task for Connell Wagner was to undertake a site visit of the locality to familiarise themselves with the area. This was followed by intensive on-ground studies including flora and fauna investigations which commenced around September.
Connell Wagner’s aim has been to gather as much information as possible at the start of the project, so that the Project Application and the accompanying Preliminary Assessment Report submitted to the Department of Planning in November 2007 was as comprehensive as possible. Connell Wagner’s work on the environmental impacts and mitigating measures proposed by Hunter Water will be reported in the Environmental Assessment Report (EAR) which is expected to be submitted to the Department of Planning for consideration around mid 2008. The EAR will subsequently be placed on public exhibition for comment by interested members of the community and other stakeholders.
Road Relocation Design
Opus International Consultants are undertaking the design of the new roads required as part of the project. With origins in the former New Zealand Ministry of Works and Development, Opus brings together the experience of more than a century of infrastructure development covering planning, design, project management, construction supervision, maintenance and rehabilitation. Opus has been operating in Australia since 2000 and has completed numerous road and bridge projects for the RTA, local councils and rail authorities.
Following on from the preliminary work already completed by consultants GHD to identify the preferred “low” road option, Opus will complete their work in two phases – Concept Design and Detail Design.
During the concept design phase, preliminary geotechnical investigations and hydrological studies will be completed. As a starting point, Opus will be looking at the indicative “low” road option identified through the recent comprehensive stakeholder consultation. This route will be further refined through detailed modelling of the terrain, geotechnical and hydrological parameters to fine-tune the road alignment, long-sections and cross-sections. This process may result in some adjustment to the indicative route once actual conditions on the ground are more thoroughly investigated and known. This work is expected to be completed around April 2008.
Opus will then proceed to the detail design phase which will involve detailed geotechnical and hydrological studies necessary to develop the design to the level required for construction. This work is expected to be completed by the end of 2008.
Hunter Water will also engage independent consultants to undertake road safety audits and design reviews of the designs prepared by Opus.