The culvert at Saratoga-Sunnyvale Road was widened and the upstream detention basin completed in September, 2011. Steelhead trout (coastal rainbow trout) ("Oncorhynchus mykiss irideus") occurred historically in Calabazas Creek but have not been seen since the 1970s. Leidy (2005) identified at least several impassable barriers to migration upstream from the Bay including a inclined dam at Comer Drive, and drop structures at Bollinger Road and Rainbow Drive. The latter two have now been removed, and the Comer Dam, which was constructed in 1973 to trap gravel and cement debris from the upstream Cocciardi Quarry (closed for several years now), has raised the creek to within four feet of the underside of Comer Drive bridge posing a flooding threat to the bridge. It was scheduled to be removed by the SCVWD. Leidy (2007) identified three species of native fishes in Calabazas Creek: California roach, Sacramento sucker, Three-spined stickleback ("Gasterosteus aculeatus"), and rainbow trout ("Oncohrynchus mykiss") (now extirpated). Non-native fishes include goldfish ("Carassius auratus auratus") and Western mosquitofish ("Gambusia affinis").