After last nights earthquake just outside of Truckee, CA (4.7 Magnitude Earthquake Last Night in Tahoe! | Did You Feel it?) we thought it would be a good time to dust off this old post from May.
The VICIOUS Martis Creek Dam!!! don, don, DONNNNN! photo: dailymail.co.uk
A new fault was found in California this week that goes right thru Truckee, misses the Martis Creek Dam by 200 yards, and almost makes it to the shores of Lake Tahoe. This new fault is called the Polaris Line as it goes thru the former mining town of Polaris, CA just outside Truckee, CA.
The New Polaris Fault Facts:
– 22 mile long fault (compared to 800 mile long San Andreas Fault)
– Capable of a 6.9 magnitude earthquake on the Richter Scale
– Last time this fault shifted was 15,000 years ago (within 35,000 years is considered “active” by Army Corps)
– Essentially runs right underneath Martis Creek Dam, Truckee, and Northstar Ski Resort
– Martis Creek Dam is one of ten dams in the US that is considered “urgent & compelling”
– There are already two other known faults in the Martis Creek flood plane area
– This fault is really not that big of a deal
One of the dangers that the media is hyping with this, is that the Martis Creek Dam could be destroyed by the fault as the dam is only 200 yards from the new fault. If this happened, the release could flood a small portion of Reno downstream.
Yeah, I suppose that is a “danger” but it seems like there would be a good amount of warning time (the dam is 35 miles upstream from Reno) and it really just doesn’t seem like that much water. Granted it’s enough to cause a flood, but this is no tsunami typa situation. Some calculations say if it did flood, it could potentially affect 16,000 homes in Reno to some degree.
“We weren’t expecting it at all,” Lewis Hunter, a senior geologist with the Corps, told OurAmazingPlanet.
The US Army Corps of Engineers found this fault with it’s fancy laser detection system called LiDar (Light Detection And Ranging). LiDar shoots laser pulses into the ground from an airplane and uses computer software to create highly detailed topographic maps of the earth.
In the past 20 years the California Geological Survey has found 50 new faults in California. This is cool, and it’s good to document ’em, but it shouldn’t be too surprising as California is thought to have thousands of faults criss-crossing the state every which way you can imagine.