Within any residential zone district, an entry driveway, or a walkway may cross any yard area except that no driveway shall be within 10 feet of a side yard line or within 15 feet of a rear yard line. Within a nonresidential zone district, entry driveways and walkways may cross any yard area; however, other than crossing yards, driveways shall adhere to the yard requirements for accessory structures or as otherwise specified by the zone district regulations. Walkways in a nonresidential zone may be located in a yard area but they shall not encroach into any required buffer.