During an incident, responders may need to balance the intensity of their response approach against potential congestion delays. Often, these decisions must be made in real time using available data. As one example, a responder may decide to push a crashed truck to the shoulder and risk damaging the cargo. Based on discussions with first responders, this study identified data needs to support cost-benefit decisions made by on-scene incident managers. Procedures for estimating the impacts associated with an ongoing incident are described, considering capacity reductions, queuing, economic losses from congestion, and risks of secondary crashes. These procedures could be encoded in a spreadsheet for dispatch use or as a web site or smart phone application for use at the incident scene.