Such parking or loading facilities may be enclosed within a building or may be open. All spaces for parking, loading and access, except in single-family residence lots, shall be graded, surfaced, drained and adequately lighted and suitably maintained in the manner and to the extent necessary to avoid dust, erosion, and excessive discharge of collected surface water onto public streets or adjacent property. The spaces and access areas shall be so arranged as to afford clearly safe and convenient maneuvering room, entrances and exits in light of the volume and frequency of expected parking, loading and unloading. The access areas shall be so connected to a public street as to avoid unsafe driving conditions and traffic congestion.