(a) The department is expressly prohibited from making or contracting any debts or entering into any contract for which it does not have sufficient funds appropriated at the time of making said debt or entering into said contract to enable it to meet such debt or such contract obligation. However, such prohibition shall not apply to contracts entered into pursuant to Article IX, Section III, Paragraph I and Article VII, Section IV, Paragraph IV of the Constitution of Georgia; and the department is expressly authorized to enter into such contracts and to obligate the department in connection therewith. For the purpose of paying obligations imposed by any such contract, such funds as may be appropriated to the department for activities incident to providing and maintaining an adequate system of public roads in the state and the cost incident thereto may be pledged by the department.

(b)(1) The board shall not enter into any lease contract if:

(A) The aggregates of all lease rentals from that and all other such lease contracts including the contract or contracts proposed to be entered into exceed $19,900,000.00 per annum or 15 percent of the funds appropriated to the department in the fiscal year immediately preceding entering into any such lease rental contract, whichever is greater; or

(B) Such lease contract constitutes security for bonds or other obligations issued by the lessor.

(2) The execution of any lease contract is prohibited until the General Assembly has specifically provided funds in an appropriations Act for the payment of at least one year's rental under such contract.

(c) The department is prohibited from entering into any contract for the purchase of supplies, materials, and equipment, except as authorized by Article 3 of Chapter 5 of Title 50.

(d)(1) The department is prohibited from negotiating any contract for the construction or maintenance of a public road involving the expenditure of $50,000.00 or more except any contract:

(A) With counties, municipalities, and state agencies, provided that such negotiated contract shall be made at the average bid price of the same kind of work let to contract after advertisement during a period of 60 days prior to the making of the contract;

(B) With a railroad company or utility concerning relocation of its tracks or facilities where the same are not then located on a public road and such relocation is necessary as an incident to the construction or improvement of a public road. However, nothing contained in this subsection shall be construed as requiring the department to furnish a site or right of way for railroad or railway lines or tracks or utility facilities required to be removed from a public road. Furthermore, this subsection shall not prevent the department from assisting in the removal and relocation of publicly owned utilities from locations on public roads as provided in Code Section 32-6-170; (C) For emergency construction or maintenance involving the expenditure of $50,000.00 or more when the public interest requires that the work be done without the delay of advertising for public bids;

(D) For the procurement of business, professional, or other services from any person, firm, or corporation as an independent contractor; or

(E) With the State Road and Tollway Authority.

(2) A department contract negotiated and made with a political subdivision, as authorized by subparagraph (A) of paragraph (1) of this subsection, may be subcontracted to any person or political subdivision. It may be performed with inmate labor, except in the case of a public work constructed with federal aid, or the forces of such political subdivision or those of a political subdivision to which such contract has been subcontracted. However, the department shall have the authority to furnish planning, contract plans, specifications, and engineering supervision over a public road being constructed by a political subdivision or by its subcontractor. Any subcontract made under authority of this subsection shall not constitute the basis of any claim against the department, nor shall such subcontract be considered an assignment of the rights of the political division under its contract with the department.

(e) Except for public roads within and leading to state parks, the department is prohibited from maintaining any public road not on the state highway system. Any department contract with a state agency or political subdivision for construction of a public road not then, nor to become upon completion of the contract, part of the state highway system or a road within or leading to a state park shall not relieve the agency or the political subdivision of the responsibility for maintaining such public road as such duty is imposed by this Code section and by Code Sections 32-4-41 and 32-4-91.