In mid-July, the New Zealand Hydrological Society (NZHS) conducted a 4 day training workshop in the use of Space Time Image Velocimetry (STIV) techniques for stream discharge measurements. The workshop was led by Mark Randall (Senior Project Officer Water Services, North Region, Queensland Department of Natural Resources, Mines and Energy) who has experience in this emerging technology.

Fully subscribed, the course was attended by over 30 technical field hydrologists from a majority of regional councils around New Zealand as well as some vendor and surveyors. (There was even a participant from the often forgotten Australian Regional Council!)

STIV is part of a cluster of non-contact measurement techniques. This includes Particle Tracking Velocimetry (PTV) and Large Scale Particle Image Velocimetry (LSPIV), which utilise video imagery of stream surface velocities and the application of appropriate algorithms and stream hydraulic assumptions to generate stream mean velocities and hence indirect calculation of stream discharge.

Other non-contact techniques include radars (fixed and handheld) to measure surface velocities but still need the application of correct algorithms to produce discharge measurements of suitable accuracy.