25 CFR 170.442 - What is the IRR Inventory?
(a) The IRR Inventory is a comprehensive database of all transportation facilities eligible for IRR Program funding by tribe, reservation, BIA agency and region, Congressional district, State, and county. Other specific information collected and maintained under the IRR Program includes classification, route number, bridge number, current and future traffic volumes, maintenance responsibility, and ownership.
(b) Elements of the inventory are used in the Relative Need Distribution Factor. BIA or tribes can also use the inventory to assist in transportation and project planning, justify expenditures, identify transportation needs, maintain existing IRR transportation facilities, and develop management systems.