Ultrasonic seismic methods can be used in the condition assessment of bridge decks by evaluating changes in material characteristics and detecting the development of defects and zones of deterioration. The impact-echo method is of special benefit in the evaluation of corrosion-induced deck delamination because of its nondestructive nature and ability to detect delaminated zones at various stages of deterioration: from initial to progressed and developed. The traditional approach in the condition assessment of bridge decks by impact-echo is based on a review of individual test-point records. A new approach based on three-dimensional data visualization is proposed. The developed three-dimensional visualization platform allows for both the advanced presentation and an automated interpretation of impact-echo data. The data presentation is provided in terms of three-dimensional translucent visualizations of reflectors in a bridge deck section and horizontal and vertical cross sections through all distinctive zones, including a zone of delamination. The associated interpretation platform enables the overall assessment of the condition of the deck, through cumulative distributions of reflection intensity of different reflective layers, and the identification of deteriorated zones of the deck to be repaired or rehabilitated in an efficient and intuitive way.