Manukau Courier : December 30th 2010
www.manukaucourier.co.nz Thursday, December 30, 2010 We wish all our readers a very happy New Year. Our office is closed for the holidays and will reopen on January 6. A special issue will be in your letter- box on January 6. One big happy family Proud dad: Site foreman Rangi Williams at the stretch of the Puhinui Stream that his Leighton Works team has realigned to make room for the new SH20 westbound on- ramp at Roscommon Rd. The on-ramp and Cavendish-Puhinui link road are due to open on January 5, completing the four-year $220 million SH20-SH1 extension he's worked on from the start. Photo: SIMON WATTS By KAREN MANGNALL HAPPY eels, happy fish and soon happy motorists. That s what site foreman Rangi Williams is hoping for next Wednesday when the SH20 westbound on-ramp at Roscommon Rd finally opens for traffic, weather permit- ting. His Leighton Works crew has spent weeks permanently realigning a 150-metre stretch of the Puhinui Stream to make room for the onramp and Cavendish-Puhinui link road. We ve moved it 100 metres to the west, he says. The new stream s about the same depth as before but has more of a high flow . Eddies and kinks have been built to slow the waterflow and make the stream more environ- mentally friendly for fish , Mr Williams says. It s got little rock pools designed so they can have a little rest. And with river pebbles brought in to line its banks, the realigned stream is prettier than the old, over- grown stretch. The realignment was done in three stages. Water was drained from the old stream and its fish, eels and other aquatic life scooped out and moved to their new home once each stretch of the new channel was excavated. The design, construction and transfer were all done under the watchful eye of freshwater ecologists and Auckland Regional Council experts. It s been very hard work, Mr Williams says. But the hardest job is yet to come and will be completed after the on-ramp and link road are open. We have to block the stream under the bridge and put rock armour from one side of the stream to the other. It will strengthen the stream bed and the bridge, he says, but has to be done when the flow is at its lowest. The risk is we ve got to work inside a four-day win- dow. So it s not allowed to rain because if we have more than 6mm of rain, water will come up to the high flow mark, he says. Once that s done, the stream banks will be planted with native trees and shrubs to prevent sediment runoff and to provide habitats for wildlife. We want to leave it in a better condition than we found it, Mr Williams says. The soft bed of the old stream has been excavated and some 20,000 cubic metres of engineered fill have been layered over it to form the on- ramp and link road. Now contractors are going flat tack to finish off the road surfaces in time for Wednesday s opening. Completion will end Mr Williams four years as site foreman for that stretch of the southwestern motorway extension. And after tidying up a few loose ends he s quite clear on what s next: A holiday. The on-ramp opening will complete the $220 million SH20-SH1 motorway exten- sion started in 2006 by the New Zealand Transport Agency. The Cavendish-Puhinui link road will provide a non- stop run to the airport from the southern motorway, Auckland state highways manager Tommy Parker says. The 4.5km extension is part of the western ring route between Manukau and Albany, a 48km alternative to the southern motorway and Auckland harbour bridge.
December 23rd 2010
January 6th 2011