In 2000 the Surfrider Foundation constructed an artificial surfing reef in El Segundo, CA as mitigation for a lost surfing resource. Because it did not improve surf quality and had begun to deteriorate, plans were initiated to remove the reef in the fall of 2008. Phase I of the reef removal process took place during the Fall of 2008 and Phase II of the removal process took place during the Fall of 2010. You can learn more about this ASR in the documents below.
Surfrider Foundation has developed a Policy on Artificial Surfing Reefs.
Surfider Foundation's Jim Moriarty has written several blog posts about various aspects of artificial surfing reefs.
Also see Can artificial surf reefs reduce crowds? by Surfrider's Chad Nelsen.