On June 5, a council officer inspected the stream around Fabian's Culvert observing a significant volume of wet, muddy material piled along the banks containing gravel, silt, cobble and a small amount of vegetation. Among the material the officer identified were dead or dying eels and koura (freshwater crayfish).
An investigation found the material had been excavated from the stream bed extending along a section of the stream bank more than 1 kilometre long, spanning five paddocks Hammond leased or owned.
Excavation of the stream bed resulted in permanent loss of aquatic life by death and injury due to the mechanical activity especially for longfin eels, given they enter a low metabolic state during winter and were, therefore, slower to escape machinery, the summary says.
The work had also made the stream bed less stable, likely resulting in ongoing issues with turbidity and suspended sediment in the area, affecting downstream habitats.
"These effects could last several months until the plants and stream bed recover."
Runoff from the bordering farm during rainfall could result in repeated episodes of sediment suspension.
Suspended sediment chokes gills of fish and invertebrates, reduces visual range for sight-feeding fish and impairs migratory ability, having a negative effect locally and downstream until plants grow again in the excavated bed.
Maximum penalty for the charge is two years' jail or a $300,000 fine.
Hammond, who was represented by James Gallagher, was remanded at large until January 13 when a date will be set for sentencing in Wellington District Court before an environment court judge.