If the township board of any township which is located in a county operating under the county road unit system and which township shall not have made an ad valorem tax levy for its general fund for one (1) or more years immediately preceding shall determine, by resolution, there is a surplus in the general fund of such township, then said township board may direct the treasurer of such township to pay a stated amount of such surplus out of the general fund of such township to the county treasurer, and upon receipt of said payment the county treasurer shall credit the same to a special fund and the board of county commissioners shall expend such special fund for the construction and maintenance of roads in the township from which such payment was received, which expenditure shall be in addition to funds expended by the county in such township from the regular county road and bridge fund.