Abstract: Runoff water from parking lots and filling stations is cleaned by first passing via an inlet pipe tangentially into a vortex chamber where the swirling action separates the contaminants from the water. Floating contaminants are stored in the vortex chamber, trapped at the top of the chamber by the roof of that chamber and at the lower part of the chamber by a skirt. That roof has an access opening to permit removal of the floating contaminants. The body of the fluid thereafter moves downward into a settling chamber where heavier-than-water contaminants settle. As the fluid in the settling chamber builds up, it passes through cleaning screens to a clean water outlet. A by-pass overflow pipe to process very large volumes of water extends upward from the settling chamber. Each screen may have louvers for preventing contaminants from blocking the screen.

Abstract: A large vault or tank receives the runoff water to be cleaned. There are one or more small tanks in the large tank (vault). Each small tank is inverted and receives water at its open lower end, from the large tank. The water entering the small tank rises, as the water level in the large tank rises, and flows upward through a filter. When the water level rises above the top of the filter it enters an outlet tube or pipe and then flows downwardly along the center-line of the filter. A float, a valve and a check valve may cause the system to function as a siphon and feed the filtered clean water to an outlet. Alternatively the siphoning effect will occur if the inside diameter of said outlet tube is small enough to form a partial vacuum.

Abstract: Runoff water from parking lots and filling stations is cleaned by first passing it via an inlet pipe tangentally into a vortex chamber where the swirling action helps to separate the contaminants from the water. Floating contaminants are stored in the vortex chamber, trapped at the top of the chamber by the roof of that chamber and at the lower part of the chamber by a skirt which is part of the chamber and extends downwardly for a limited distance from the inlet pipe. That roof has an access opening to permit removal of the floating contaminants. The body of the fluid thereafter moves downward into a settling chamber where heavier-than-water contaminants settle to the bottom where they can be removed during regular cleaning. As the fluid in the settling chamber builds up it passes through cleaning screens to a clean water outlet. A by-pass overflow pipe to process very large volumes of water extends upward from the settling chamber and ultimately feeds the outlet pipe.