Colorado gets a player to be named and cash in the deal.
San Diego announced the move Wednesday at baseball's winter meetings, where two days earlier former Padres closer Heath Bell was introduced by the Miami Marlins after they signed the three-time All-Star to a $27 million, three-year contract.
The 28-year-old Street, who had 29 saves in 33 chances for Colorado in 2011, now gets to call pitcher-friendly Petco Park home after three seasons at Coors Field.
"It won't be tough at all," Street said about changing home parks. "Everybody likes pitching at sea level better than pitching at 5,000 feet. I don't believe in making excuses. That being said, you can get the same results either place, but obviously Petco Park is known as a pitcher's park. That's someplace I'm excited to pitch in."
Street was 1-4 with a 3.86 ERA in 62 games this year in Colorado, where he said he loved his time and was treated first-class. The right-hander has 178 saves in seven seasons with Colorado and the Oakland Athletics.
"We're happy how it ended up. He's a very proven closer. He's done it in this division, he's had three good years in Colorado, which is a very hard place to pitch," new Padres general manager Josh Byrnes said. "We're glad to have him."
Street is due $7.5 million next season, $500,000 of which the Rockies will pay. His contract also includes a $9 million player option for 2013 that includes a $500,000 club buyout that Colorado would pay as well.
Bell, who had more than 40 saves in each of the last three seasons in San Diego, converted 43 of 48 save chances with a 2.44 ERA this year.
Though San Diego had offered salary arbitration to Bell, Byrnes stayed in contact with his former boss, Colorado GM Dan O'Dowd, about a possible deal.
"It's been going on at least a month," said Byrnes, who was hired to be O'Dowd's assistant in Colorado in 1999 and held that role for two years. "We were able to stay in touch about this idea and ultimately get it done."
Street said he didn't really know about the possibility of going to San Diego until getting a text from a friend Wednesday morning and later a call from O'Dowd.
Street has a 4.11 ERA in 97 career games at Coors Field. He hasn't allowed an earned run in his 11 appearances at Petco Park, where he has 17 strikeouts and three walks while opposing batters hit only .132 against him in 11 1/3 innings.
"For whatever reason, I've always felt like I've had good stuff when I've been there, or pitched well when I got there," Street said. "I'm real excited to pitch there. Pitching at sea level is going to be big help. ... I love being at sea level. My body feels great."
Once Bell made his move this week, the Padres sped up the process to fill the void. There were other trade talks and discussions with free agents in Dallas before finalizing the deal with the Rockies.
"Even a week or two ago, we thought we might have to wait and see," Byrnes said. "Heath signed. These meetings prompt activity. We were in the middle of that. In the sense of timing, it was time to go."
Street was on the 15-day disabled list in August with a strained right triceps, but returned to pitch nine games with a 2.45 ERA the rest of the season. He had right shoulder inflammation in 2010.
Byrnes said Street finished last season healthy and that the Padres were comfortable after reviewing the closer's medical report.
"Heath was very durable. That's part of being a closer," Byrnes said. "Huston's been durable, but we wouldn't have gone for it if we weren't comfortable on that (medical) side."
Street allowed a career-high 10 homers this year, but had a career-low nine walks. His 6.11:1 strikeout-to-walk ratio was the best in his seven major league seasons.