<![CDATA[Riverbank protection projects are susceptible to delays caused by fluctuating river discharge, tidal conditions, adverse weather, and restricted working hours. Such delays can increase project costs and reduce the effectiveness of disaster mitigation measures. This study evaluated the cost efficiency of accelerating the Masangan Riverbank Protection Project in Pasuruan Regency using the Critical Path Method (CPM). A quantitative approach was applied using secondary data, including the work breakdown structure, baseline schedule, activity durations, work volumes, progress reports, S-curve, and project cost documents. CPM calculations were used to identify critical activities based on earliest start and finish times, latest start and finish times, and zero float values. Acceleration was implemented by adding workers to critical activities while maintaining eight working hours per day and six working days per week. Workforce additions reduced the durations of K-175 concrete work, rubble masonry, and weep-hole installation from 42 to 30 days, although direct labor costs increased. The respective cost slopes were IDR 668,824, IDR 1,637,280, and IDR 818,640 per day. K-175 concrete work was identified as the most economical acceleration alternative, whereas rubble masonry represented the highest additional cost. The integration of CPM and cost-slope analysis supported selective schedule acceleration by prioritizing critical activities that achieved the greatest time reduction with the lowest additional cost.]]>
