[Code of Federal Regulations] [Title 23, Volume 1] [Revised as of April 1, 2002] From the U.S. Government Printing Office via GPO Access [CITE: 23CFR661.25] [Page 322] TITLE 23--HIGHWAYS CHAPTER I--FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PART 661--INDIAN RESERVATION ROAD BRIDGE PROGRAM--Table of Contents Sec. 661.25 What are the criteria for bridge eligibility? (a) Bridge eligibility requires the following: (1) Have an opening of 20 feet or more; (2) Be on an IRR; (3) Be unsafe because of structural deficiencies, physical deterioration or functional obsolescence; and (4) Be recorded in the national bridge inventory (NBI) maintained by the FHWA. (b) Bridges that were constructed, rehabilitated or replaced in the last 10 years, will be eligible only for seismic retrofit or installation of scour countermeasures.