W Line 900NB Pipeline

Contact Energy

November 2012

Wairakei, Waikato

Length: 1.3km

Size: 900NB

Warner Construction won the tender to connect the Pipeline to the Otupu wells from an existing reinjection line in the Wairakei steam field.

The W-Line pipeline was approximately 1300m long and 900NB 16mm wide, in addition the Otupu wells were hooked up to the pipeline and an outage was required to complete the tie in.

The pipeline followed a difficult route between the side of the highway and the Prawn Park, over a creak and through several culverts including a culvert under the main highway.

Warner Construction completed W-Line pipeline on time, to budget, with no quality issues and with an excellent safety record of no incidents.

The W Line is a 900NB pipeline and is located at the Contact Energy Wairakei Power Station in Wairakei, Taupo.

A new 900NB reinjection pipeline was required to transport the additional reinjection water produced by the new Te-Mihi Power Station to the Otupu reinjection wells located beside the main Taupo bypass highway.(ETA)

Te-Mihi Steam Field provided energy for the existing Wairaki and Poihipi Power Stations and the new Te-Mihi Power Station. The overall development included new production and reinjection wells, flash plants and pipelines.

Steam was supplied to the new power station by a common 1800 manifold. Warner’s installed the manifold and connected the Steam Lines. Also included was the installation of three new IPSGW dump stations and associated pipework.

Majority of the pipe was 1050NB and 750NB spiral pipe totaling 7km in length. The remainder of the pipe welding was in sizes ranging from 25NB to 500NG with the pipe wall thickness ranging from 9.5mm to 25mm.