Overview
This work was to perform inspections and erosion mitigation for approximately 450 linear feet of exposed pipeline as a result of flooding conditions on the Missouri River.

Scope of Work
The scour mitigation took place in water depths that ranged from fifteen feet to thirty-five feet of water depth and in currents that were five frames per second, or greater. Ballard arrived on site and performed multi-beam inspections to determine the extent of the scour mitigation needing to take place. During the pre-mitigation surveys, materials, equipment, and material placement barges were mobilized to site, as well as construction of a sandbag batch plant. Once fully mobilized, sandbags were placed around, adjacent to and on top of the exposed pipeline to support and protect it from additional erosion. After this was complete, larger stone and rip rap were placed over top of the sandbags to add additional protection from the high river currents.

Innovative Solutions
Throughout this process, daily multi-beam surveys were conducted to track where the sand and rip rap was being place and to ensure that the pipeline scour area was being fully mitigated and protected.

Results
The scour mitigation project was completed on time, within budget, and with a safety excellence record.