Hay fire snarls traffic on Highway 99

Traffic on southbound Highway 99 through Modesto was backed up for hours Wednesday as firefighters worked to extinguish dozens of hay bales that caught fire while being hauled by a big rig.

The driver pulled over north of Kansas Avenue around 11:30 a.m. and called 911 to report the hay bails on fire.

Two lanes were immediately closed as firefighters isolated the effected trailer and began working to extinguish the fire.

The process took hours because every hay bale had to be offloaded, spread out and extinguished, said Modesto Fire Chief Alan Ernst.

Hay bales are compressed very tightly ... so the fire burns very slowly and creates an immense amount of heat so it is a laborious process,” he said. “Typically on a farm you just let the fire slowly consume the hay but on the freeway we can’t do that.”

Two engines, two water tenders and a front loader to spread the hay responded to the scene.

Ernst said it appears the fire might have been related to a mechanical failure on the big rig but the cause remains under investigation.

As of 4:15 p.m. firefighters were still on scene and the right lane remained closed.

This story was originally published October 17, 2018 at 4:19 PM.