Ala. Code § 11-6-4
When any county has established the office of county engineer or chief engineer of the division of public roads the Director of the Department of Transportation shall, upon application of the county commission, authorize the expenditure out of the available funds of the State Department of Transportation, of an amount equal to 70 percent of the annual salary of the engineer to such county, which shall apply to the payment of the annual salary of the engineer, with such payments to be made in equal monthly installments; provided, that the amount contributed or paid by the State Department of Transportation to any county, not including retirement contributions, shall not exceed 70 percent of step 18, or the top step, whichever is greater, of the salary schedule under the Professional Civil Engineer II, Senior classification in any one year.
Ala. Code § 11-6-4 (1975)