As of 3 September 2008 more than 800,000 homes in Louisiana are still without electricity due to Hurricane Gustav. The storm damaged a main transmission line in southern Louisiana; officials do not yet know when power will be fully restored. Oil and gas installations in the Gulf of Mexico sustained no significant damage from the storm. Residents will be officially allowed to return to New Orleans on 4 September. Authorities have lifted checkpoints on highways and roads leading to some parts of the city as residents start returning to Jefferson, St. Tammany, St. John and St. Charles parishes. Orleans parish will remain closed until 2359 local time on 3 September. Many areas of New Orleans still lack electricity and other utilities. However, Entergy, an electricity company, has repaired several damaged transmission lines and hopes to gradually restore power on 3 September. Few businesses are open in New Orleans; most grocery stores and gas stations remain closed.