Tex. Transportation Code § 373.052

(a) The local toll project entity has the first option to develop, finance, construct, and operate a toll project. The local toll project entity must exercise its option not later than the later of:

(1) the 180th day after the date on which notification under Section 373.051(a) is provided or notification under Section 373.051(b) is received; or

(2) if the United States Department of Transportation Federal Highway Administration issues a record of decision for an environmental impact statement submitted by the department under Section 373.051(b)(2) more than 60 days after the date the department provides notice under Section 373.051(b), the 120th day after the date the record of decision is issued.

(b) The option period under Subsection (a) may be extended an additional 90 days by agreement of the department and the local toll project entity.

(c) If the local toll project entity exercises the option under Subsection (a), the local toll project entity after exercising the option must:

(1) within 180 days after the later of the date of exercising its option or the date on which all environmental approvals necessary for the development of the toll project are secured and all legal challenges to development are concluded, advertise for the initial procurement of required services, including, at a minimum, design services, for the project; and

(2) within two years after the later of the date of exercising its option or the date on which all environmental approvals necessary for the development are secured and all legal challenges to development are concluded, enter into a contract for the construction of the toll project.