When the Levee Breaks

[rlown]

I can only imagine the fun lil' white dogs have in red mud..

[maverick]

http://ww2.kqed.org/lowdown/2015/09/21/ ... alization/

[rlown]

And I-80 had to come to the party: http://www.pressdemocrat.com/news/66521 ... artslide=0

[SSSdave]

What tends to make me shake my head is various civil engineering projects that claim such and such is going to protect against 100 or 200 or 500 year projected floods.

http://www.sfgate.com/bayarea/article/C ... 921370.php

https://en.wikipedia.org/wiki/Great_Flood_of_1862
snippet:

The entire Sacramento and San Joaquin valleys were inundated. An area about 300 miles (480 km) long, averaging 20 miles (32 km) in width,[15] and covering 5,000 to 6,000 square miles (13,000 to 16,000 km2) was under water.[9] The water flooding the Central Valley reached depths up to 30 feet (9.1 m), completely submerging telegraph poles that had just been installed between San Francisco and New York. Transportation, mail, and communications across the state were disrupted for a month

Every time I drive across I205 to I5 crossing the San Joaquin River at Lathrop, I just shake my head. All this was under 8 feet of water in 1997. So why did those authorities subsequently allow thousands of new homes to be built right along the river? Because they built some levees to protect them against a theoretical 200 year flood. Just last month during the storms, water was within a standing person of the levee top.

...probably because greedy pinheads in real estate corps backed by bank loans with their buddy politicians are well intent on making money and by time the flood comes they will be long gone down in Palm Springs in CA or Palm Beach in FL hitting little white balls.

http://www.mantecabulletin.com/section/ ... le/141027/

http://www.mantecabulletin.com/section/ ... le/141228/

Just one more storm series this winter in near term like 1997 1986 1969 1983 or 1955 and...when the levee breaks.

David

[Lumbergh21]

Water is cresting Oroville dam tonight, and though it's not being reported, Shasta Lake is very close to the top. Unless the next storm shown for Tuesday is a complete dud, expect severe flooding in Shasta, Butte, and Tehama counties as Shasta Lake will be full, and they won't be able to keep flows below 70,000 cfs. And, we haven't even reached spring run-off when the flows traditionally peak. That peak has the potential to be very devastating this year as we sit at 110% of the normal April 1 snow pack here in Northern California on February 10. But, don't let any of this fool you, we are still suffering through a drought and water conservation will be mandated. Guess the Governor thinks it's necessary in order to keep the oceans full.

[rlown]

my last two weekend chances of duck hunting were blown out end of Jan because the refuges were flooded/closed. We were saturated then.. This is just icing on the cake. As Dave points out, planning against the theoretical doesn't always work out the way humans plan.

When I was a teen, we marveled at the flooding in Fairfield. Schools closed, but we rode our bikes there in axle deep water anyway just for fun. After that flooding was forgotten, they built houses on the fields that were 4' deep in run-off from that flooding. Good luck with that decision.

And 37 is still shut down: http://www.pressdemocrat.com/news/66543 ... artslide=0

..McGuire met with state and local officials Friday at the flood zone, which is in the area of Novato Creek, east of where Highway 37 connects with Highway 101 in Marin County.

McGuire said an estimated 330 million gallons of water has inundated the highway at that location. Caltrans has been using pumps in an effort to drain the water.

McGuire said the flooding was exacerbated by a number of factors, including silt in Novato Creek that has decreased its capacity.

He said a levee along Arroyo Creek also was breached in two places, flooding a pasture that then spilled over onto the highway.

McGuire said Marin County and Caltrans officials will work with the private property owner to repair the levee.

McGuire said the highway where it flooded has sunk two-and-a-half feet over the years, according to initial surveys. Highway 37 was constructed in stages along marshland skirting San Pablo Bay.

Caltrans’ current plans call for raising a 3,000-section of the highway in both directions by as much as five feet to gain clearance over future floods, McGuire said.

He said the earliest the repair work is expected to begin is sometime in March.

Funding for the $8 to $11 million project will come mainly from Caltrans’ general fund, McGuire said.

[Gazelle]

It is now going over the emergency spillway at Orville 1st time ever! Would not want to be below that!

[ERIC]

What tends to make me shake my head is various civil engineering projects that claim such and such is going to protect against 100 or 200 or 500 year projected floods.

http://www.sfgate.com/bayarea/article/C ... 921370.php

https://en.wikipedia.org/wiki/Great_Flood_of_1862

Not quite apples to apples. 1997, agree with your point. But none of the large dam or conveyance projects were around in 1862. While current engineering would indeed be challenged to handle a year like that, the impact WOULD NOT be 1862-like on the Valley floor, which is in effect, an endorsement for the engineering's very existence.

Just one more storm series this winter in near term like 1997 1986 1969 1983 or 1955 and...when the levee breaks.

Mmmm...likely not. The state's projects are being managed right now with those scenarios in mind. Keep in mind that snowpack and weather forecasting have come a long way in recent decades. That's been a game changer for flood management.

And finally, related and worth mentioning for those following this thread, a common misunderstanding is that a 100 -year flood is likely to occur only once in 100 years. In fact, a 100-year flood has a 1 percent chance of occurring in any given year. We've had multiple "100 year events" in the past 100 years.

[ERIC]

[rlown]

at least we get to dry out a bit here. News reports said last night Oroville was 7' below the emergency spillway and the rate of rise was 1/2 foot per hour. That is a lot of water running off. Thanks for the twitter video, Eric.