Driving next to Lake Grassmere near Seddon

Categories: Marlborough Region

Tags: driving, lake grassmere, marlborough, new zealand

Added: 2 years ago

Driving next to Lake Grassmere, near Seddon in the Marlborough Region, on the Northeast Coast of New Zealand's South Island.

Lake Grassmere is a large shallow lake with ponds used for natural salt production. The white mounds that appear on the shoreline in the video are salt.

Lake Grassmere gets filled with seawater pumped fresh from the nearby Pacific Ocean. Warm north-westerly winds that blow across the lake surface are used to evaporate the water and concentrate salt. The salty water is pumped into deep holding pens and shallow crystallization ponds. As the water evaporates, salt forms as a crust on the bottom of the ponds. Any remaining water is pumped out, with the dried salt harvested, crushed, washed, and moved by giant conveyor belts to form vast mounds of sparkling white crystals. The pink-to-purple colour of the crystallization ponds happens because natural microscopic green algae change to pink at the high salt concentration. The same phenomenon gives the Red Sea its name. Small pink shrimps in the water also live happily in this salty environment. Most salt works in the world are usually closer to the equator. Still, Marlborough's warm north-westerly winds, long hours of sunshine, and low summer rainfall allow the evaporation needed to obtain salt from the sea at this latitude.