When stoplogs failed at Hebgen Dam’s 93-year-old intake tower in late summer, Barnard participated in the emergency repair for PPL, Montana LLC to stop a 3500 cfs uncontrolled flow. On scene with few hours’ notice, Barnard teamed with the owner and engineer to assist in a damage investigation complicated by extremely turbulent flow. The use of sonar and underwater cameras helped identify a126-square-foot gap created by missing stoplogs. Constructability review and resource management followed. Barnard maintained a 24/7 work shift through the peak of the repair work and continued to offer support as permanent remedies were being developed.