Project overview
Location Marlborough
Scope $120K
Date of completion May 2019
The existing stopbank protecting the Moleta Vineyard was two-thirds eroded prior to works commencing. If this bank were eroded entirely, the river would flood, damage and erode the adjacent vineyard.
Overview
Delegat Limited, one of our key vineyard clients, appointed us to the Moleta Gravel Extraction and Rockwall Stage II project. Stage II was done only three weeks after Stage I, where the bulk of the 7000m3 river extraction was done, and a rock wall of 160m to the same design was built.
The project was done in less than two weeks. All Simcox plant, people and rock from our own drill and blast Barracks quarry and from the river extraction that was done during Stage I on site by Simcox. Large diggers and dump trucks were used to extract 1000m3 of river gravels. 1,100T of medium and toe rock (this sizing means each rock was up to 10T or in other words, one rock filled the whole truck deck) was brought in and placed as well.
Once the 80m rock wall was built, nine 2.5T concrete blocks with wire rope in-between were installed by Simcox. Then willows from the surrounding riverbank were lashed to the wire rope and partially covered with gravel to further support the bank against scouring.
Challenges
On this project, we had the walk the diggers into the river alignment to divert it out about 50m from the bank that we were protecting. This had to be strictly done all in accordance with the resource consent which had conditions on residual flows for fish passage, and no fords under running water, meaning we had to put temporary culverts in and remove them on completion.
We had to programme a large amount of machinery and people for the right weather window where the river was low enough to do this work. The large supply of rock had to be coordinated with our quarries’ forward orders, planning and other projects.
Awards
Finalist - CCNZ Nelson/Marlborough Branch Awards 2019.
