Heritage Trails Program. Out of the amounts appropriated above, the Texas Department of Transportation shall make available $1.5 million from the federal Transportation Enhancement Program funds administered by the department for the Heritage Trails Program project whenever such projects are approved by the Texas Historical Commission's Heritage Trails Program and meet federal funding requirements of the Transportation Enhancement Program as defined by federal Department of Transportation, Federal Highway Administration federal regulations in Title 23 of the United States Code. The Texas Historical Commission in conjunction with the Texas Department of Transportation will review the Heritage Trails Program project to determine if the Heritage Trails Program meets the federal Transportation Enhancement Program guidelines in Title 23 of the United States Code. It is the intent of the Legislature that funds appropriated above would cover the costs of administering the Heritage Trails Program approved for federal Transportation Enhancement Program funds. In addition, the Texas Department of Transportation may redirect obligated funds previously obligated for courthouse preservation under the Transportation Enhancement Program to other available projects should the Heritage Trails Program fail to receive federal approval or federal Transportation Enhancement Program funds are not available due to changes in federal laws, rules, regulations, or appropriations.