A substantial database exists on water quality after aerial 1080 possum
and rabbit poisoning operations in New Zealand. However, no water
quality investigations have been undertaken to assess the effect of a
ground-based 1080 poisoning operation. This is due to the perception
that manual application of toxic bait is less likely to result in significant
quantities of bait entering watercourses compared to aerial application.

A meeting with Dr Gillian Durham, the then Director of Public Health, at the
Ministry of Health on 19 February 1999, discussed model permit
conditions, in particular the requirements for drinking water supplies and
monitoring. At the meeting it was agreed that the perceived risk from
ground applications of 1080 was much lower than from aerial applications
and that was why statutory requirements were much less involved for the
former.

It was agreed that the Wellington Regional Council would monitor a
ground 1080 operation and report on water quality effects, so that the
Ministry could promulgate national advice on the appropriate approach to
ground application of 1080.

This study provides support for the assertion that ground-based 1080
possum-poisoning operations do not have a measurable effect on water
quality.