16.25.110   Dikes, diversion walls, and catchment basins drainage.
   A.   Drainage shall be provided at a consistent slope of not less than one percent away from tanks and fittings to a sump, drain box, or other safe means of disposal located within the diked impounding area and at the greatest possible distance from the shell of the tank to provide drainage sufficient to prevent overflow of the dike and to effectively control the flow of fluids and runoff. Traps shall be provided with no less than six inches of liquid seal provided between the sumps, drain boxes, or drains intended for the disposal of spills. Catch basins or traps used for tank farm drainage shall not connect directly to the city sewer system. Fluids shall be pumped or gravity fed into a tank, interceptor outside of the tank containment, or diked area or directly into a pipeline for that purpose.
   B.   Drains shall not discharge to adjoining property, public sewers, or drainage ways unless the drain is designed to prevent the release of flammable or combustible liquids.
   C.   A valve, operable from outside the dike, shall be provided in the drain system and shall normally be kept closed.
   D.   Control of drainage shall be accessible under fire conditions. This includes, where deemed necessary by the inspector, installation of piping accessible to the public right-of-way for removal of firefighting waters from diked areas.
   E.   Approved provisions shall be made for disposing of water and of oil retained by dikes or impounding or catchment basins.
(Ord. 90-08-1074 § 4 (part))