Photo by Christine O'Connor.
Willowbank Fire Station Senior Station Officer Kerry McNamara said the spill was caused by a broken fuel line on a bus about 10am.
Diesel from the bus flowed about 80m down the street to Regent Rd.
He declined to name the bus company.
Initially, a Downer street cleaner was sent to clean up the diesel, but it began to slip in the fuel and became stuck on the steep slope of the street.
Dunedin City Council contractors were then sent to spread grit on the road so the street cleaner could gain traction.
No-one was injured in the incident, Mr McNamara said.
