In all zoning districts, murals, exclusive of any sign area, painted on walls of a building, fence, or similar structure shall be permitted; provided that a permit therefor is obtained from the Development Services Director and that such mural shall not interfere with traffic or present any other hazard or detriment to the public health, safety, or general welfare. The murals shall be maintained properly, to include correcting any peeling or fading of paint, and to repair the mural if maintenance is required.