Dockworkers are walking picket lines at major East and Gulf coast ports, with consumers likely to feel the impact in coming weeks should it continue.

For U.S. ports, there were many bouts of congestion. Demand for goods that were either more or less popular than they would normally be became volatile. Shortages of truckers and other freight service providers wreaked havoc on land-based and maritime transportation networks.

The International Longshoremen’s Association and United States Maritime Alliance announced that their 45,000 port workers, who cover 36 ports along the East and Gulf coasts, would go on strike on Oct.

The dockworkers strike goes more than a few weeks, a work stoppage would significantly snarl the nation’s supply chain, potentially leading to higher prices and delays in goods reaching households and businesses .