The state's budget surplus is estimated at $27 billion and Phelan believes the number could rise to $30 billion soon after the legislature convenes in January.
"I just want to remind everybody it's in our coffers because of inflation, because of pain," said Phelan at a gathering of the Transportation Advocacy Group.
While many in Texas are calling for additional property tax relief, Phelan believes the windfall represents a rare opportunity to significantly upgrade the state's aging and increasingly inadequate infrastructure.
"I've got elected officials saying we need to spend all the new revenue on property tax relief. Let me just remind you, none of this money came from property taxes. It all came from sales tax," said Phelan.
Phelan advocated investing much of the surplus on a range of projects including highways, bridges, water systems and coastal protection.
The legislative session is scheduled to begin on Jan. 10, 2023.