The City Council received the U.S. Army Corps of Engineers findings report today regarding the April 30 temporary flood protection breach. The report concludes the breach was caused by the barriers sliding under river pressure as a result of too little friction between River Drive and the barrier caused by plastic sheeting and wet surfaces.
Based on the report, multiple changes to the flood operations plan will be instituted as recommended by the Corps of Engineers.
Read the report here. Read the presentation to City Council here.
Watch a video of the presentation made to City Council Tuesday:
Under ideal circumstances, the report finds that the barrier should’ve stood against river pressure; however, the barriers likely began to slip due to wet pavement and plastic sheeting conditions. Canadian Pacific operations were not a cause of the breach, according to the report.
The Public Works Department will be making changes to its flood operations plan based on the report. Those changes include reducing the risk of slippage by changes to plastic sheeting installation, double-stacking flood barriers at a forecast flood height of 20 feet or more and developing an emergency communication plan for flood plain properties within the protected area.
Changes in the flood plan will be implemented immediately and employees will be trained on the new methods recommended by the Corps of Engineers report prior to the next flood event.