Mossburn residents are being urged to urgently conserve water, as there is an extreme danger the township will run dry, Southland District Council (SDC) says.

Residents are asked to not wash vehicles, hose gardens or lawns, including hand held. 

This follows one of the town's two water bores running dry and its second bore unable to keep up with today's expected usage.

The SDC advises Mossburn's second bore is only producing 4 litres per second which is equal to the town's off peak usage.

The town's reservoir is at just 40%, SDC says.