The provisions of Sections 47-5-451 through 47-5-469 of this chapter are cumulative and shall not be construed to repeal or supersede any laws directly inconsistent herewith; and it is specifically provided herein that any work program in operation or functioning pursuant to any local law when Sections 47-5-451 through 47-5-469 of this chapter become law may be continued pursuant to such local law and shall not be affected in any way by Sections 47-5-451 through 47-5-469 of this chapter. The county board of supervisors conducting such program may, however, at its option, convert the program to a program to be governed by Sections 47-5-451 through 47-5-469.