Thousands were out of their homes for the holiday and strict bans on fireworks sought to prevent new fires from igniting in the hot, dry conditions.
San Luis Valley
The fire had previously burned through 104 structures, including family cabins. It is the third largest in state history.
Fire containment stands at 5 percent as more resources have been added to the fight, including two Air Force MAFFS air tankers.
"It's a very challenging fire, I'll be honest with you, with all the wind changes," said incident commander Shane Greer.
US 160 remains closed between Fort Garland and La Veta due to fire activity along the highway.
The Federal Emergency Management Agency said Thursday the U.S. government would help pay the state's cost for fighting the fire.
The fire, which was reported early Wednesday, is zero percent contained.
Conejos, Las Animas, Chaffee, Otero and Alamosa counties and the city of Alamosa have filed suit in U.S. District Court.
While Costilla County has only 3,524 residents, due to its unique history it has more than 45,000 landowners, mostly absentee.
"There is no proposal to offer any leases in the San Luis Valley,” said BLM spokesman Steven Hall.