Bruce Webb Dam

Overview

This vineyard water storage pond was tendered for and successfully secured following the completion of significant earthworks for Pukaka Limited. Work began in February 2019 with an estimated completion date of October. But by putting enough resources to build two dams into the one project, we were able to complete it three months ahead of schedule.

The project involved earthworks embankments up to 11m high, spillway construction (including a manhole and outlet pipe) and irrigation pipe outlet beneath, and through, the main embankment.

Finishing works included a surface water diversion drain; HDPE dam lining, placement of armour rock to the spillway and diversion drain outlets, re-top soiling and grassing of disturbed areas, and a road running the course of the top of the embankment. Dam lining was completed by our long term dam lining partners Viking Containment.

Challenges

To get to the site, first we had to design and construct a steep road that allowed truck and trailer access, with close grade control and no flat spots. Our project manager and D8 dozer made quick work of both, respectively.

With the project kicking off during wine growing season, water was also at a premium. Our preferred irrigation was unavailable as they needed water for their grapes, so we used our water carts to drain nearby stock ponds.

While constructing the access road, our Dozer operator moved excess material to make the walls of the dam less steep. With two crews working in close proximity inside the dam, this made easier and safer for them to work.

There was also a stock dam on the boundary of our site that we protected with a silt fence; confined to two gullies with two of the now empty stock ponds sitting as silt detention ponds. We added further protection downhill of earthworks with silt fences on the back sides of both ponds.

Awards

Finalist - CCNZ Nelson/Marlborough Branch Awards 2019.