A fire destroyed a 200-yard long Union Pacific Railroad trestle sending black smoke billowing into the sky Tuesday morning north of River Islands at Lathrop.
The loss to the trestle was pegged at nearly $1 million. Fire officials were investigating to see whether occupants of a nearby homeless encampment — just upwind from the fire — had anything to do with the fire.
Billowing black smoke from the creosote-soaked wood could be seen rising into the sky in downtown Manteca shortly after 9 a.m.
Lathrop-Manteca Fire Chief Gene Neeley said his department received a call of a grass fire in the area. On their arrival they saw flames from burning weeds near the timber supports below the railroad trestle.
Neeley said he immediately called a second alarm with Ripon, Tracy, Manteca and Montezuma departments responding to the blaze.  Union Pacific crews fought the fire from above on rail cars while up to 50 firefighters attempted to put out the fire engulfing the bridge from ground level.
The mutual support brought four water tankers to the scene as well to feed the engines’ tanks that were quickly running out of water.
Chief Neeley said firefighters discovered the homeless camp where the weeds burned with the wind keeping the camp upwind and untouched by the fire.  There were two tents, he said and they are presently looking for a person of interest who may have caused the fire.
He said he was first concerned the tracks might be used by the ACE train but later determined ACE is not involved in the westbound right-of-way.
Firefighters were on the scene for five hours and the UP crews were expected to be there throughout the night to guard against flare ups from hot spots in the remaining timbers.
Directly across the river to the west were the River Islands’ new homes, with the developers’ offices even nearer to the fire’s location. Only yards away from the affected tracks were older homes on Queirolo Road, as were newer homes south of Lathrop City Hall. They were not affected by the thick smoke which, fortunately, was driven in a southeast direction by the wind, away from the residential areas.

South Manthey Road closed; freeway
traffic unaffected
The section of South Mantey Road from Queirolo Road was closed to traffic while fire personnel brought the fire under control. Manthey runs over the bridge and past the former Stewart Road where River Islands offices and the popular DelOsso Farms are located. The road closure also meant access to the Mossdale Landing Park and Boat Ramp was temporarily unavailable.
The cloud of smoke gradually turned from black into charcoal gray, making it look less threatening, as the creosote from the railroad ties was consumed by the fire. The dark brown oil distilled from coal tar is used as a preservative for railroad ties as well as utility poles and marine pilings.
Traffic movement on I-5 just south of the Mossdale Bridge did not appear to be disrupted by the smoke, although it went at a slower pace than usual.
Trains run by the Mossdale Bridge tracks as many as four times during any 24-hour period, “night and day,” said longtime Queirolo Road resident Ida Queirolo whose family has farmed the fields north of the tracks for three generations.