Catch basins shall be constructed either of brick, concrete or cast iron. If of brick or concrete, they shall be at least 36 inches in internal diameter from the base to one foot above the outlet, and may taper to not less than 24 inches internal diameter at the top. Each catch basin shall be covered at the grade level with a stone, iron or cement concrete cover having an opening of not less than 18 inches diameter and fitted with an iron lid. No stone cover shall be less than two and one-half inches in thickness. The walls of the catch basins, if of brick, shall be not less than eight inches thick and laid in portland cement mortar, plastered outside and inside below the outlet with a half inch coat of portland cement mortar. The bottom shall be at least eight inches thick, composed of either brick laid in cement mortar or of portland cement concrete. The brick used shall be hard burned sewer brick. The bottom of catch basins shall be at least two feet below the invert of the outlet to the sewer. The outlet shall be trapped to a depth of eight inches below the invert of the outlet to the sewer to prevent the escape of grease. The trap shall be a six-inch heavy cast iron T provided with an approved clean-cut plug not less than four inches in diameter, or a similar contrivance. The invert of the inlet to the catch basin for kitchen wastes shall be not less than two feet four inches above the finished bottom of the catch basin.
(Ord. 703, passed 10-10-1983)