Two Tauranga companies have been slapped with a $75,000 fine for discharging sediment into the Kopurererua Stream.

Comanche Holdings and TBE 2 discharged sediment rich water into the stream as they were developing the Tauriko Business Estate in April.

Conditions of their resource consent meant that water had to be treated before being put into the stream.

In sentencing, Judge Harland says this was a serious breach.

She says the discharge reduced the productivity of the stream's ecosystem, plant and sea life.