Hawkes Bay Dairy Effluent Pond
The dairy effluent pond on McLaughlin's dairy farm in Central Hawkes Bay was completed in one and a half days. Geotextile bidim was installed along the slopes of the dam, with a soft limestone floor. Once again, high density polyethylene geomembrane liner was used to cover the pond, with all welds being tested to recognized international specifications.
Manawatu Dairy Effluent Ponds
The Walsh project in Marton involved lining a 2900 square-metre dairy effluent pond with accompanying 900 square-metre oxidation pond. A protective carpet of A14 bidim was deployed beneath a layer of 1.5mm HDPE liner in both ponds, with an extrusion-welded polylock-lock sealed weeping wall filter system installed between the two.
The project - including fusion-seaming of the liner panels, extrusion-welding, pipe perforations, testing and safety ladders - was completed in four days.
Waikato Dairy Effluent Pond
Another dairy effluent pond, this time near Morrinsville, the Airlie Lodge dam required 3 800 square-metres of liner on top of a 600 metre Wavin Bande Solpac gas venting system, designed to prevent gas build-up beneath the liner. The Bande Solpac is deployed in a grid system, with each length of venting strip terminating at a gas vent welded into the liner.
The 2700 square-metre JonesAg dam was another project requiring polylock - this time embedded in a corner wall - allowing us to connect liner to concrete with an extrusion weld that can then be tested using the spark-test method: Copper wire is installed into the seam prior to welding, and an electrical current is passed over the completed weld, making it possible to identify any weakness in the extrudate.
Central Otago Jenny Roberts
The Jenny Roberts frost-protection dam brought together the irrigation and dam-lining divisions in a turn-key project near Cromwell. After installing the frost-protection system for the Roberts' cherry orchard, a 3000 square-metre dam was lined with geotextile, geomembrane, with separate pipe inlet and outlet, and a three-metre wide swale, acting as an overflow spillway.