Relative effects of river flow, water temperature and abstraction on trout in the Torepatutahi stream

Report: TR 2001/09

Author: D Speirs & I Kusabs

Increasing demand for water for out of stream uses such as irrigation and community supply have the potential to adversely effect the value of the Torepatutahi stream as a significant habitat for resident trout populations and as cold water refuge for trout from the Waikato River. Changes in water level resulting from increased out of stream water use also has the potential to reduce the area and quality of marginal wetlands in the mid reaches of the stream.

In order to investigate these potential effects Waikato Regional Council conducted detailed investigations on the fishery, flow regimes and temperature of the Torepatutahi Stream over a four month period.