The union representing 45,000 dock workers on the U.S. East and Gulf Coasts and their employers on Wednesday said they reached a tentative deal on a new six-year contract, averting further strikes that could have snarled supply chains and taken a toll on the U.

The United States Maritime Alliance said on Wednesday it reached a tentative agreement on a new six-year master contract with the International Longshoremen’s Association.

Dockworkers represented by the International Longshoremen’s Association negotiated to avoid a second port strike in a matter of months.