New concerns are being raised about the low river flow and water quality issues in the Hutt River.
Wellington Fish and Game has carried out drift dive surveys in the river, looking at trout numbers to give an indication of the health of the waterway.
Manager Phil Teal says they've found the trout population's in pretty good health, but the quality of the water lessens as you go downstream.
He says the flow's restricted to a trickle at times due to draw-off for the town's water supply.
He says the number of medium-sized trout observed is encouraging though, with an improvement from two years ago.