The apparatus and methods of the present invention enable efficient and appropriate treatment of Urban Water Runoff, so that the treated Urban water Runoff can be can be introduced into public waterways without contaminating such waterways. The system apparatus utilizes adsorptive Organoclay media, mechanical filtration and ultraviolet sterilization. The methods and apparatus of the present invention remove contaminants from Urban Water Runoff to a level which enable the resulting effluent to meet appropriate standards for introducing the treated Urban water Runoff in to public waterways. The method and apparatus of water treatment of the present invention does not utilize chlorine containing compounds which, when combined with organic compounds can produce THM's that can become problematic when re-introduced to the downstream environment. The systems of the present invention can be made sufficiently compact so as to enable their use in remote locations.