Abstract: The apparatus is a surface water purifying catch basin which uses a lamella separator to separate out fine sediment and a separate chamber to trap heavy debris, oil, and floating debris. The surface water enters an inlet chamber which is separated from a settling chamber by a divider wall that has a lower opening between the chambers and a higher overflow. The inlet chamber traps floating contaminates and those that are heavier than the water. The opening between the chambers permits the surface water to flow into and through the lamella separator. The catch basin exit is from the settling chamber, but the water can reach the exit only through the lamella separator that separates out the fine sediment in the water. All of the accumulated contaminates can be removed through access holes in the top of the catch basin.