F1PART IXFUNCTIONS OF LOCAL AUTHORITIES IN RELATION TO WATER QUALITYApplication and interpretationF133.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Duties of local authorities: supplementary provisionF134.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .