On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

SHMAK water quality – visual clarity

There are two methods to determine visual clarity in SHMAK; the clarity tube (or SHMAK tube) and the black disc method.

SHMAK Water Quality – Visual Clarity

There are two methods to determine visual clarity in SHMAK; the clarity tube (or SHMAK tube) and the black disc method.