The worst infrastructure disaster in America is looming in the delta of the Sacramento and San Joaquin Rivers, about 70 miles northeast of San Francisco. In this area, rich farmlands are protected by hundreds of miles of simple dirt levees. If/whenever an earthquake were to wipe the levees out , the agricultural lands they protect will flood, triggering a chain of events that would pull salt water from the Bay area into the delta, and contaminate the drinking water supply for half the population of California. And the ramification of that ? According to University of California Geologist, Jeffery Mount, it is shutting off the water supply for 25 million people for 2-3 years.
And the culprit ? Same old one > INFRASTRUCTURE. The levees around the delta farmlands were built by farmers 150 years ago. They built the levees on poor foundations, mostly sand and lightweight peat, which deforms easily under pressure. The foundations are so porous and leak so much that most of the delta islands would fill up with water in 3 months, if they weren't continually pumped out. Making this worse, over time, the islands have sunk, and are below the water line by about 25 feet. So the levees are holding back water ALL the time, and have to be very strong for that daunting task - but they're not.
The levees are :
1. on bad foundations
2. poorly constructed
3. working 365 days/year
Thus, it will be no surprise when they fail. Not if, but when.
The delta streams provide 1/2 the drinking water of California, from San Francisco to Los Angeles. They flow into a massive reservoir 89 miles southeast of San Francisco called the Clifton Forebay. According to Doug Thompson of the California Dept.of Water Resources, if it wasn't for this system, California would be "dry down south".
The water is pumped into a 440 mile long series of aqueducts delivering to southern California, its drinking water. This whole fragile system would be pretty secure if it wasn't for one thing > Earthquakes. Something that happens a lot in California, Trust me, they happen a lot. I lived there for 12 years, and I've been through my share of them. In fact they are actually occuring all the time, except that almost all of them are too small to be significantly measurable, or cause damage.
A quake that is large and near the delta though, would knock out the delta levees and pull salt water from San Francisco Bay to the Clifton Forebay (California's water supply). Here's the likely scenario. A 6.7 quake with an epicenter close to the delta occurs. The levee foundations turn to mush creating sinkholes, collapsing the levees. The sunken island farmlands are turned into salty seas, after a few days. The islands flooding is so powerful, it pulls 300 Billion gallons of salt water inland, all the way to Clifton Forebay, which then has to close its gates, to prevent contamination of the reservoir.
California would have to ration the water in the Forebay, but it would run out in about 6 months, and it would take 2-3 years for the delta to return to normal (assuming perfect conditions that whole time, ie. no earthquakes). Bay area experts say there's a 66% chance that a 6.7 earthquake or a large flood will take down the levees some time over the next 30 years. The 1989 (world series) quake (6.9) just missed. It was centered in Boulder Creek , CA, about 120 miles southwest of the delta.
COST to fix ? Authorities estimate it will take $25-40 Million per square mile to quake-proof the delta levees. Money that California does not have. It would have to come from the federal government. So what is California doing about this catastrophe waiting to happen ? They have been shoring up the levees with sloping and adding rocks, but those treatments are like giving aspirins to a cancer victim. Bottom line is California has no plan for dealing with this catastrophic threat.
Source : The HISTORY CHANNEL.
And the culprit ? Same old one > INFRASTRUCTURE. The levees around the delta farmlands were built by farmers 150 years ago. They built the levees on poor foundations, mostly sand and lightweight peat, which deforms easily under pressure. The foundations are so porous and leak so much that most of the delta islands would fill up with water in 3 months, if they weren't continually pumped out. Making this worse, over time, the islands have sunk, and are below the water line by about 25 feet. So the levees are holding back water ALL the time, and have to be very strong for that daunting task - but they're not.
The levees are :
1. on bad foundations
2. poorly constructed
3. working 365 days/year
Thus, it will be no surprise when they fail. Not if, but when.
The delta streams provide 1/2 the drinking water of California, from San Francisco to Los Angeles. They flow into a massive reservoir 89 miles southeast of San Francisco called the Clifton Forebay. According to Doug Thompson of the California Dept.of Water Resources, if it wasn't for this system, California would be "dry down south".
The water is pumped into a 440 mile long series of aqueducts delivering to southern California, its drinking water. This whole fragile system would be pretty secure if it wasn't for one thing > Earthquakes. Something that happens a lot in California, Trust me, they happen a lot. I lived there for 12 years, and I've been through my share of them. In fact they are actually occuring all the time, except that almost all of them are too small to be significantly measurable, or cause damage.
A quake that is large and near the delta though, would knock out the delta levees and pull salt water from San Francisco Bay to the Clifton Forebay (California's water supply). Here's the likely scenario. A 6.7 quake with an epicenter close to the delta occurs. The levee foundations turn to mush creating sinkholes, collapsing the levees. The sunken island farmlands are turned into salty seas, after a few days. The islands flooding is so powerful, it pulls 300 Billion gallons of salt water inland, all the way to Clifton Forebay, which then has to close its gates, to prevent contamination of the reservoir.
California would have to ration the water in the Forebay, but it would run out in about 6 months, and it would take 2-3 years for the delta to return to normal (assuming perfect conditions that whole time, ie. no earthquakes). Bay area experts say there's a 66% chance that a 6.7 earthquake or a large flood will take down the levees some time over the next 30 years. The 1989 (world series) quake (6.9) just missed. It was centered in Boulder Creek , CA, about 120 miles southwest of the delta.
COST to fix ? Authorities estimate it will take $25-40 Million per square mile to quake-proof the delta levees. Money that California does not have. It would have to come from the federal government. So what is California doing about this catastrophe waiting to happen ? They have been shoring up the levees with sloping and adding rocks, but those treatments are like giving aspirins to a cancer victim. Bottom line is California has no plan for dealing with this catastrophic threat.
Source : The HISTORY CHANNEL.
