In 2010, New York City began a four-year project to upgrade and reactivate the flushing tunnel. According to "The New York Times", the proposed plans included steps to "reconstruct the motor pit and replace the propeller with three modern vertical turbines; clean, patch and smooth the interior of the tunnel; replace the broken sewer pipe and encase it in concrete to improve water flow; and reduce the amount of sewer overflow into the canal by increasing capacity at a nearby pumping plant". Increasing oxygen content was a major goal of the project. The original plans were modified in 2012, after Hurricane Sandy, to protect critical equipment from flooding. In 2014, following completion of much of the work, the tunnel was reactivated at a cost of $177 million.