No building or other structure shall be erected within the width of a visual corridor above its lowest level, as established pursuant to Section 62-512 (Dimensions of visual corridors), except as provided in this Section. Permitted obstructions within visual corridors in all districts shall include:

1. permitted obstructions listed in Section 62-611, provided that no shade trees shall be planted within 15 feet of the centerline of a visual corridor, except when provided within an open parking lot;
2. permitted obstructions listed in Section 23-311 (Permitted obstructions in all yards, courts, and open areas) and 23-312 (Additional permitted obstructions generally permitted in all yards), as modified for waterfront yards in Section 62-332;
3. boats, ships or other vessels, and floating structures permitted by paragraph (a) of Section 62-25;
4. any moving or parked vehicles; 
5. street furniture, including but not limited to, carts and open display booths; and
6. swimming pools, provided no portion projects more than 18 inches above the lowest level of a visual corridor.