A kilometre of spilt milk on State Highway 1 had minimal environmental impact, Environment Southland says.
A Fire and Emergency New Zealand spokesman said crews responded to reports of a milk tanker spilling its load in the northbound lane of State Highway 1, near Brydone, between Nicholson Rd and Ota Creek Rd, about 3pm on Sunday.
Two pumps and two tankers initially responded, and a further three tankers were later sent to help the clean up.
The spill was about 1km long and there were concerns it was starting to dry, the spokesman said.
A Waka Kotahi New Zealand Transport Agency alert said the road was closed while the spill was cleaned up.
It was reopened about 6.45pm.
Environment Southland compliance manager Donna Ferguson said milk had a high oxygen demand, which meant if it entered a waterway it could impact the ability of species to thrive.
The road and drainage ditches were affected by the spill, so the incident had only a minimal effect to land and no ascertainable effect to water, she said.
Alongside firefighters, sucker trucks were brought in to clean out roadside ditches.
An investigation had been completed but until it was reviewed and the file closed, no further comment would be provided, Ms Ferguson said.
