The most technically challenging section of the construction of Tauranga's Southern Pipeline will cost the city council $21 million.
It involves thrusting the pipeline under the bed of Tauranga Harbour from Memorial Park to Matapihi Peninsula.
Work on the sub-marine crossing was due to start in March, with the $99 million pipeline from Maleme St to the Te Maunga sewage treatment works due for completion by December.
Council communications adviser Marcel Currin said the harbour crossing contract was won by the local arm of Fletcher Construction, Brian Perry Civil.
"This is the last major work for the Southern Pipeline."
Once the pipeline had been thrust under the harbour, it would join the section of pipeline already laid along Matapihi Rd.
Responding to Bay of Plenty Times questions, Mr Currin said construction of the pipeline through orchard land from Matapihi Rd to SH29 was due to take place late this month after the avocado crop had been picked.
Construction of this section of the Southern Pipeline to the edge of Rangataua Bay stalled last year when trustees from an adjoining Maori land trust locked the orchard access gates, preventing council contractors from accessing the construction corridor along what the council said was an unformed legal [paper] road.
It followed years of opposition from some residents of the largely Maori-owned peninsula to the pipeline being laid through the middle of their lands because of cultural sensitivities surrounding human waste.
The Southern Pipeline will carry human and industrial waste from Tauranga's rapidly expanding southern suburbs. Construction was driven by the looming crisis which already saw manholes popping at critical low points in Tauranga's sewerage system whenever it rained heavily.
Maori trustees challenged the paper road, with one trustee Hayden Henry saying earlier this year it was about Matapihi's cultural relationship to an ancient path which the council said it owned. Trustees from another block took issue with the forced removal of six avocado trees in the path of the pipeline.
A declaratory High Court judgment was sought by the council, resulting in Justice Christian Whata ruling in favour of the council, saying he was satisfied that the strip was intended as a public road.
The sub-marine crossing of Tauranga Harbour was also the least favoured option for Maori who would have preferred the less risky and culturally preferred solution of bridging the pipeline over the harbour.
However, hopes to hitch the pipeline onto the 91-year-old Matapihi railway bridge ended when Kiwi Rail indicated to the council in 2010 that it was not in a position to commit to its share of the bridge strengthening needed to take the Southern Pipeline.
Two consents for the sub-marine crossing were granted last year, one by the city council on September 14 and the other five weeks later by the Bay of Plenty Regional Council.
Construction noise limits have been set by the city council, as measured from any residential house and the Matapihi Primary School. Limits during weekdays and Saturdays ranged from 60 decibels at night to 80 decibels during working hours, with the noise during the breakfast period allowed to reach 65 decibels on weekdays and 45 decibels on Saturdays.
Noise peaks of up to 95 decibels would be allowed during the working day from 7.30am to 6pm.
The regional council's consent asked for an environmental risk management plan that identified potential issues including spills and breakdowns and where in the system these issues could occur.
Southern Pipeline Progress
- Original completion target early 2010
- Laying of pipeline began mid 2010
- Current completion target December 2017