This was treated as a variation to the initial project contract, which involved installing an extra 270 metres of 560mm pipe from the initial contract end point into the Tainui Subdivision to help boost their supply.
Although this extension was straight-forward in comparison to the main contract it still had its challenges. These included drilling under the Avalon Drain and negotiating the newly installed services within the subdivision. The Connell Contractors’ team was lucky enough, on this stage, to be able to weld the pipe within the subdivision and have room to move it around relatively easily.
An offset special had to be fabricated at the tie in point to allow the pipe to rise quickly after the main services trench to connect to the tee installed by another contractor. Large bore, long radius bends were used to tie into the end of line valve previously installed by Connell.
Sheetpiles had to be used to make the connection as ground conditions were wet and the depth of the connection was 3.6 metres.