Nelson Waste Water Holding Ponds

This was an interesting job that involved rock lining the separation bunds of the effluent ponds at the Nelson Waste Water Treatment site. The large surface area and location of these ponds meant wind was able to create waves on the surface of the pond causing erosion of the bund walls. Our brief was to line these bund walls with 250mm rock to protect them.

Two crews were initiated onto the site with the job taking 2 weeks to install a total of 1482m3 of rock which, totalled 1949 linear M of bund protected. The material was crushed by a subcontractor at a local quarry before being trucked to site, it was then placed with just 5tonne excavators as these were the largest that were able to fit on the bunds.

This was an interesting exercise for those involved with the staff members working on the bund required to wear life jackets at all times. There were times the wind was causing the effluent to spray onto machinery and personnel causing the job to stop due to health concerns for the staff involved.