The team announced Tuesday that it signed the 24-year-old restricted free agent to a four-year contract. The terms weren't released.
Johnson led all Avalanche defensemen last season with 26 points in 73 games.
The Bloomington, Minn., native won a silver medal while playing with the U.S. team at the 2010 Vancouver Olympics.
He was drafted No. 1 overall by Saint Louis in the 2006 NHL entry draft. Colorado acquired him from Saint Louis in a trade in 2011.
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