As soon as the City Engineer has set and finally determined and established the finished grade line of any parcel of real estate, lot or land within the City, thus providing for the drainage of surface water therefrom, the owner, occupant or any other person in charge of such premises shall continue to maintain and/or adhere to such finished grade line of such premises and shall further keep all drains, ditches, swales or other surface water conductors open and free and clear of any and all obstructions. (Ord. 64-24. Passed 3-2-64.)