Weeks of predominantly dry conditions in Mid Canterbury have caused water levels at Mill Creek to continue to get lower, posing a threat to fish that inhabit the stream.
Council's Group Manager Service Delivery Neil McCann says stockwater rangers are working to increase the flow of water in local stockwater races - which supply Mill Creek - as much as possible.
The water that caters for the fish in Mill Creek comes from the same stockwater races that keep domestic stock watered.
"We'd normally see around 500-700 litres of water per second flowing down from the springs at the Winchmore intake (near the Ashburton River) into the stockwater race system and then on to Mill Creek but because of the continuing dry weather, this intake has dropped to about 90 litres per second – which translates into a trickle rather than a healthy flow.
"In the past 48 hours alone there's been a further reduction in flow.
"We're doing all that we can to keep the stockwater races wet and help preserve the fish at Mill Creek, including notifying Fish & Game New Zealand.
"We'll continue to do this until we see a sufficiently healthy water level for the fish at Mill Creek and in the meantime will work with Fish & Game.
"It's very hard to estimate how many fish may have been affected. Unfortunately the water situation at Mill Creek is just another example of what these challenging dry conditions can lead to.
"The low levels of the water at Mill Creek do not result from the current works taking place in the creek."