Late Night Visitors

First thing in the morning, our team of biologists head out to the Calaveras Dam Replacement Project construction site to inspect for animals that may have wandered onto the construction site overnight. The inspectors help to ensure that none of the rare and endangered species in the area end up in the path of the day’s construction activities. 

Sometimes they find critters that need to be taken off site to a safe place. In fact, to date, our environmental inspectors have relocated western pond turtles, Alameda whipsnakes, California tiger salamanders, and many other species to a nearby, safe habitat away from construction.

Other times they find evidence that something passed through, but didn't stick around. This last week, our inspectors found the paw print of a mountain lion at the edge of a water holding pond. Also known as a cougar, puma, or panther, mountain lions are solitary predators of other large mammals, such as deer and elk.  Males can weigh up to 200 pounds, while females could reach 140.

Glimpses of these creatures have been seen by project personnel, but thankfully, none of our biologists have encountered the feline while making their rounds. But it serves as a reminder that we are not alone out here in the watershed, and we must continue our vigilance to help protect the animals and plants in the Southern Alameda Creek Watershed while we continue with construction of this important water reliability project. 

Calaveras Critters on the Move!

If the television show Unlikely Animal Friends were to film an episode at the Calaveras Dam Replacement Project, they would have no trouble identifying symbiotic animal relationships all over the Southern Alameda Creek Watershed. Our personal favorites are ground squirrels and the threatened California Tiger Salamander.

Tiger Salamanders live underground in the burrows of other animals, quite often the burrows of ground squirrels. When the rains come to the watershed, the California Tiger Salamanders leave their burrows and make a beeline for a nearby pond where they can meet a mate and lay eggs. 

Problem is, there is a large dam construction project in the way. Our biologists placed tubs at strategic locations around the site. As they walk the perimeter of the project on a daily basis, they take the captured salamanders and relocate them to pre-designated places offsite. 

They often make sure to stick the Tiger Salamanders into ground squirrel burrows that are stable.  The ground squirrels do not seem to mind their amphibious neighbors, and provide the added benefit of digging out the tunnel should it collapse. Otherwise the salamanders would be trapped by cave-ins and might perish. Who knew?

Photo courtesy of Pete Trenum, Elkhorn Slough



For more project info, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org

We are Building a “Mini-Dam”...for the California Tiger Salamanders!

Prior to and during construction, the Calaveras Dam Replacement Project implements measures to avoid and minimize impacts to wildlife located in the Alameda Creek Watershed. 

Our Environmental team has taken proactive steps to protect and relocate the California tiger salamander (Ambystoma californiense) species since the start of the project.  The California tiger salamander (CTS) is an amphibian native to Northern California growing up to 8 inches long.  CTS have started to migrate at night from upland habitats to aquatic breeding sites, especially during the first major rainfall events of fall and early winter.

 California tiger salamander (Ambystoma californiense)

Wildlife exclusion fencing is strategically located along the boundaries of the construction work limits to deter wildlife from entering.  Also, water moistened buckets are placed in trenches between silt fences to catch the critters, which are later relocated to nearby ponds.

Just this week our approved biologist monitored berm repairs performed on a relocation pond for CTS.  The berm serves as a barrier which is positioned on the top of the pond, to reduce turbidity and maintain suitable conditions in the pond.  Permission was given by the California Department of Fish and Game to relocate 50 CTS to this location. 

As of today, 78 California tiger salamanders have been trapped and relocated to safer habitats away from project construction. With the repaired pond, we will be able to provide them a suitable and safe environment for breeding.

For more project info, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org.

Repair work on Pond for California tiger salamander

Repair work on Pond for California tiger salamander

Photo of pond after work completed

Calaveras Critters: California Tiger Salamanders on the Move

Prior to and during construction, the Calaveras Dam Replacement Project implements measures to avoid and minimize impacts to wildlife located in the Alameda Creek Watershed. The California tiger salamander (Ambystoma californiense) is an amphibian native to Northern California growing up to 8 inches long. California tiger salamanders migrate at night from upland habitats to aquatic breeding sites during the first major rainfall events of fall and early winter.


Our Environmental team has taken proactive steps to protect and relocate the California tiger salamander species. Wildlife exclusion fencing is strategically located along the boundaries of the construction work limits to deter wildlife from entering. Also, water moistened buckets are placed in trenches between silt fences to catch the critters, which are later moved. As of today, 72 California tiger salamanders have been trapped and relocated to safer habitats away from project construction. During construction biological monitors are present during initial vegetation clearing and grading to relocate any wildlife.



For more project info, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org

Photos courtesy of Bill Stagnaro, Environmental Inspector & Biologist