(a) The legislature, by law, may authorize the Texas Transportation Commission or its successor to authorize the Texas Department of Transportation or its successor to issue notes or borrow money from any source to carry out the functions of the department.
(b) Notes issued or a loan obtained under this section may not have a term of more than two years. The legislature may appropriate money dedicated by §§ 7-a and 7-b, Article VIII, of this constitution for the purpose of paying a debt created by the notes or loan.