Transportation Code §252.313

Before the commissioners court orders payment of a claim covering the purchase of equipment, materials, supplies, or services, including county road construction or maintenance, contracted for by the court, the county road engineer must certify in writing that the claim is correct and that: (1) any equipment, materials, or supplies covered by the claim conform to specifications approved by the county road engineer and have been delivered in good condition; (2) any county road department services contracted for by the commissioners court have been satisfactorily performed; and (3) any county road construction or maintenance done under the contract conforms to the plans and specifications called for in the contract.