The diesel contamination of the Makotuku Stream near Raetihi would have been a disaster in summer, says Federated Farmers Ruapehu provincial president Lyn Neeson.
Farmers reliant upon Raetihi's water supply were as frustrated as the urban residents, she said, but remained hopeful alternative water supplies would be secured by the end of this week.
But buying extra equipment to water stock is an expense they don't need, she said, and if it had happened in summer it would have been a crisis.
"With livestock understandably refusing to drink from contaminated troughs, it had been a difficult week for the affected farms and especially those who draw water from Raetihi's water supply.
"What we need now is some heavy rain and it looks like some is on the cards.