Tonkin Highway Industrial Estate Stage 1

Location: Tonkin Hwy, Bayswater

Client: Linc Property
Consultant:   JDSi
Scope of works: Bulk Earthworks (import fill, ground remediation and soils management), Civil Works, Services Relocation and Offsite Headworks
Value of works: $13.5 million


Description of works:
Buckby Contracting successfully completed the civil works for Linc Property. It involved delivering over 60 industrial lots of various sizes for the developer. The job involved many job-specific challenges, such as acid sulphate soils, unknown materials, existing services and works around a train level crossing to name a few.

Buckby Contracting’s bulk earthworks component involved several aspects: 50,000 m3 of fill was to be imported to the job site, screening of approximately 20,000 m3 existing material and treating over 50,000 m3 of acidic soils. On top of this, most of the material was below ground water and required site-specific stockpile management. This involved placing sand in certain locations to meet environmental conditions. There was an unexpected finds plan that was strictly adhered to due to the previous use of the site.

The location had to be serviced by an offsite sewer headworks component involving slurry microtunneling, 650 m in the middle of Railway Parade. This was drilled under Tonkin Highway, under existing steel gas and water mains and along fibre optic cables. Manholes were up to 7 m deep along Railway Parade. Night works was required for certain works due to restrictive traffic management conditions, safety concerns and interaction of works with other contractors adjacent to the job site. All dewatering effluent was treated and sent back to the northern part of the Stage 1 civil works. NRW’s Forrestfield Railway Duplication works occurred towards the south of the sewer works and drilling had to occur simultaneously. Buckby Contracting successfully met the requirements of all stakeholders involved and did not exceed the original budget of the works.

The civil works packaged involved 25,000 m2 of roads, 5,000 m of drainage and 2,500 m of internal sewer. It also involved a large 8,000 m2 impermeable basin surrounded by a retaining wall. There were significant engineering challenges in construction of the works due to the high ground water table of this job site with significant changes continuously due to the site constraints.