The original Marion Road Trunk Main was a DN600 locking bar mild steel pipe installed in 1898. Due to frequent failures, SA Water engaged BJ Jarrad to renew approximately 6km of this main through either relining of the existing pipe or new direct buried pipe.
Tonkin Consulting was engaged by BJ Jarrad to complete the detailed design, undertake a safety in design review, document the ‘as constructed’ drawings and provide technical advice during construction.
The design included longitudinal sections along the length of the trunk main and typical details of the various fittings, connections and valve assemblies.
The design included three different pipe materials (HDPE, DICL and MSCL), and connections between these new materials and existing pipes. Custom design was required particularly for connections to existing MSCL pipe with non-standard external diameters. Tonkin Consulting’s documentation of design reviews streamlined SA Water’s review process, while clearly defining any disputes.
One major lesson learnt was the importance of accurate service locations when planning any construction activity.
The design process was fast tracked to enable the commencement of construction to minimise the overall project timeline. Therefore a further lesson learnt was that a robust document control system is critical to ensure the correct information is provided from the designers to the construction crews on site and vice versa.
Teamwork with Tonkin Consulting, BJ Jarrad and SA Water personnel has ensured the success of this project with minimal roadwork disruptions to the community.