Any district in the Lake Tahoe Basin which is able to provide to incorporated territory contiguous to such district a sewer system and treatment facilities sufficient to handle and treat any resultant sewage and provide transportation facilities sufficient to transport any resultant sewage effluent outside the Lake Tahoe Basin may annex such territory in the manner provided in the District Reorganization Act of 1965 unless the city of which such territory is a part provides or has undertaken to provide such sewer system, treatment and transportation facilities.