What It Means
A functionally obsolete bridge does not meet current design standards for lane width, shoulder width, vertical clearance, or alignment. This classification is separate from structural deficiency — a bridge can be structurally sound but functionally obsolete because it was designed for different traffic patterns. Common examples include narrow two-lane bridges on roads that now carry four lanes of traffic. Note: FHWA retired this classification in 2018, but the concept remains important for understanding bridge adequacy.
Frequently Asked Questions
What does "Functionally Obsolete" mean?
A bridge that was built to standards that no longer meet current traffic demands or design requirements.
Why does Functionally Obsolete matter for bridge safety?
A functionally obsolete bridge does not meet current design standards for lane width, shoulder width, vertical clearance, or alignment. This classification is separate from structural deficiency — a bridge can be structurally sound but functionally obsolete because it was designed for different traf...