For the past 20 years, we have been monitoring management by the Santa Clara Valley Water District (SCVWD) of temporary dams on the Guadalupe and Coyote river systems. The purpose of these dams, which were designed for removal during the flood season and then replaced in late spring, is done to ensure the annual spring migration of endangered Steelhead Rainbow Trout up stream to enable their spawning.
This video is about the danger represented by the recent failure of an abandoned eighty-foot dam connected to the Coyote Creek Metcalf Fish Ladder located in San Jose, California. A 40 foot segment tethered by steel cables collapsed during a (SCVWD) attempt to remove the dam. As result of this, dangerous conditions were created which hinder their original design purpose which was to allow endangered fish to move through the ladders.
The partially felled segment created an uphill ramp which the water had to spill over and then scoured the bottom of the creek a distance of two hundred yards with a 20 foot crater at the base on the northeast bank.
Fish in a lower pond caused by previous levee failures are trapped by the metal segment left in the stream. This is expected to trap hundreds of thousands of Steelhead Rainbow Trout and prevent their upward migration to spawn.[googlemap markerid=2]
An environmental side-issue of this results in the trapping of any natural debris or people-made garbage flowing down Coyote Creek as depicted in the video.
Failure to remove the structure in the proper time poses a dangerous risk to (SCVWD) employees when they attempt to remove barriers later during the annual flood season and possibly creating considerable damage to a multi-million dollar facility.
Complaints about SCVWD’s failure to comply with temporary dam removal during annual flood season have been filed in past years with the California Department of Fish and Wildlife (CDFW) and the Fisheries Department of National Oceanic and Atmospheric Administration (NOAA Fisheries).
Don Bernard