( CNN ) -- The U.S . Fish and Wildlife Service is battling a large grass fire in the marshlands of Jefferson County , Texas , an agency official told CNN on Tuesday . The fire began Monday afternoon about 12 miles west of Sabine Pass and about 200 yards from the Intracoastal Waterway , Jim Stockie , spokesman for the fish and wildlife service said . He estimated the area burned by Tuesday afternoon to be between 10,000 and 12,000 acres , but he said the fire was not threatening any structures . Smoke from the blaze was drifting into the Houston/Galveston area more than 100 miles from the fire . Just a dozen firefighters were working the blaze , Stockie said . `` We do n't like to put firefighters out in a sea of grass . We retreat to levies and burn off the fuel , '' Stockie said . Texas has suffered its worst fire season in state history with more than 3.5 million acres burned , according to state officials . In October , the Bastrop Complex Fire torched more than 1,500 homes and 34,000 acres of land north of Austin before officials were able to contain it , the Texas Fire Service said . An unusual La Nina weather pattern led to a nearly 11-month fire season in the state , fire service spokeswoman April Saginor said . A survey released last month by the Texas Forest Service estimated between 100 million and 500 million trees , or 2 % to 10 % of the state 's 4.9 billion trees , were killed by the severe drought and consequent fires . The dry spell that began in 2010 was the worst the state has seen since 1895 , Texas Lt. Gov . David Dewhurst has said . The drought conditions also caused concern for the state 's water supply , especially in smaller towns . CNN 's Dave Alsup and Chandler Friedman contributed to this report .
The fire began Monday afternoon . Smoke has drifted to the Houston / Galveston area , miles away . No lives are threatened ; only a dozen firefighters are fighting the blaze . ` ` We do n't like to leave firefighters out in a patch of grass , '' says an official .