Just a small update on the Fargo Bypass idea. from:
http://nwis.waterdata.usgs.gov/nd/nwis/uv/?site_no=05054000&PARAmeter_cd=00065,00060

we get that the delta from ‘very high’ to ‘record flood’ is about 10,000 cfs.
That’s a capacity almost the same as the California Aqueduct. So a concrete ditch about 20 feet x 150 feet (or 30 x 100) would carry all the ‘flood excess’ past Fargo. What’s that, 20 miles? Almost trivial in size compared to the California aqueduct. That’s the ‘cost of mitigation’…

For the inevitable complaint about the downstream effects:

ALL that water is going downstream anyway. Unlike a levee (that makes it worse) a bypass adds capacity, slows velocity, lowers the peak (downstream too!) and restores some of the natural ’spreading out’ behaviour (it just does it in a controlled place and time). So it makes it better downstream, not worse.

I do like the idea of using a tunnel boring machine to put the whole thing underground, but it adds a lot of cost…

Great Ideas,

Lets build a toolkit for deealing with the following;

Flooding adjacent to rivers:

If flood stage is low enough AND there is enough land available, low lndscaped berms could be built around the structures… with a removable floodgate allowing access.

If flood stage is higher than berms can handle, stuctures could be raised to above expected flood levels – except that accessibility for function and ADA would present another issue.

If flood stage is higher than berms can handle and we desire to actually use the structures after modification – we have two choices – move the strctures out of the way of the water OR move the water out of the way of the structures.

I see great benefits to moving the water and letting it silt out its minerals to form more growing land, and eventually provide drinking water.

I certainly hope farmers are replacing all of the 70 some odd minerals in the soil, unfortunately I do not think that they are, why not let mother nature take care o the issue for us.

Obviously, attempting to use ‘historical’ flood data without considering physical changes over time is just as ridiculous as neglecting heat islands in temperature measurements.

We could build a few more great ditches to siphon off EXCESS water in wet years, but we need to be very careful so that we allow all downstream human, animal and vegetable life to continue normally.

I agree that the entire ‘Climate Change’ phenom is little more than a massive distraction from REAL issues that require REAL TALENT to solve… the talent needs to come back in from the Mann-Hansen-Obama-Gore-UNIPCC Lunacy and get back on a real discussion based on science –

Back to designing buildings.

The web page you referenced shows maximum flows of 19800 cfm, which translates to about 560m3/s.[1m3/s=35.3146 cf/s ]This is much lower than the 3000-6000m3/s peak flows we talked about earlier at Winnipeg. The difference must be the flow at FARGO and the flow at Winnipeg . The latter receiving the flow from a much larger drain basin? Is this your understanding?

we get that the delta from ‘very high’ to ‘record flood’ is about 10,000 cfs.
That’s a capacity almost the same as the California Aqueduct. So a concrete ditch about 20 feet x 150 feet (or 30 x 100) would carry all the ‘flood excess’ past Fargo. What’s that, 20 miles? Almost trivial in size compared to the California aqueduct. That’s the ‘cost of mitigation’…

For the inevitable complaint about the downstream effects:

ALL that water is going downstream anyway. Unlike a levee (that makes it worse) a bypass adds capacity, slows velocity, lowers the peak (downstream too!) and restores some of the natural ‘spreading out’ behaviour (it just does it in a controlled place and time). So it makes it better downstream, not worse.

I do like the idea of using a tunnel boring machine to put the whole thing underground, but it adds a lot of cost…

Paul R (13:13:48) :

“And for 100 year floods to be happening twice with just over a decade between them, that’s not normal, I don’t care if you “believe” in gloal climate change or not.”

The concept of a 100 year flood is widely misunderstood. It does not mean that the floods will only occur once each 100 years it means that a flood of that severity has a 1/100 chance of occurring in any given year. As mentioned above these are random events and just like tossing double sixes with a pair of dice, you can figure out the odds of throwing double sixes in an infinite series of throws. That said if you throw a double six your odds of throwing another one on the next throw are exactly the same as they were on the first throw. Independent random events do not influence each other so you could easily have more than one 100 year flood in a single season.

The methods of flood mitigation are well known and there are lots of things communities can do to reduce their risk. The big mistake most towns make is building their flood control dikes right along the normal river channel. That gives the river no where to go as it enters flood stage. It is much better to condemn a swath of property a 1/4 mile wide or so on each side of the river and build the flood control structures set back by a 1/4 mile from the channel. You then zone the area inside this flood plain for uses that are little effected by flooding. Things like parks, golf courses, soccer fields, ball fields, City parking lots, elevated river side restaurants etc.

In some cases rather than force relocation, the property owners are offered a choice. If you relocate, we will provide a relocation incentive, but if you get flooded out, you will get no reconstruction benefits (all on your dime) and you will be on your own during the flooding period.

By providing that extra flood impoundment, you greatly slow the flood water flow rates and give it a chance to spread out and it lowers the peak crest at the exchange of a slightly longer period of flooding.

In a town north of Denver, they are built on very flat ground and during heavy thunderstorms they whole area floods. The local community has a simple solution for the problem. Instead of having to put sand bag barriers around the whole town or every structure, all the homes are surrounded by low walls with narrow access areas set up so a simple board could be slid into the gate way, and a couple sandbags is all that is necessary to prevent flooding of the homes yard.

In a known flood area, they could use landscaping to pre-place segments of a flood control structure in critical locations and during flooding their sand bag requirements would be reduced by an order of magnitude.

This has all been done in may communities, it is not rocket science, all you need is the political will and public will to work out a solution that fits the local conditions and minimizes the predictable flood losses every time it floods.

Larry

http://chiefio.wordpress.com/2009/03/31/fargo-bypass/

for more detail.

Basically, it has flooded bad before, and sometimes frequently. And what is happening now is no different than the past.

What is different is the all the man-made structures (flood controls) which can skew the data for flow rates. So estimates have to be done for comparisons from before flood control measures. In this case, all data after 1968 is estimated. Data prior to 1875 is also estimated. But that’s all we got, and have to use it. Wonder how skewed the heights are now from before flood control measures (permanent and temporary)? A 40ft flood without flood controls (allowing the river to spread out), and a 40ft flood now are not the same. Estimate the 40ft now to what it would be naturally would not be so high. Maybe by a couple feet, I don’t know.

The one thing that makes floods, and all natural disasters so devastating is the amount of infrastructure, and people in the way of them, now. It’s why they seem so much worse. The 1826 flood was the largest on record (in the Winnipeg area). It didn’t effect near the people, but was just as devastating to them, and their property. AGW theory would have been tempting to accept, then, as it is now.

Labeling events as 100yr, 500yr is extremely misleading, IMO. You can get a series of major events in one man’s lifetime, yet another man’s life may not see that many. Matter of perspective, than factual. Records are more spotty prior to the 20th century.

Here are the years with flow rates of 3000 m3/s or better up to 1998. Maybe there are records for 1999-2008 somewhere. But I’ll list what was given from the PDF.

1811 – 3171
1826 – 6371
1850 – 3002
1852 – 4672
1861 – 3540
1950 – 3058
1979 – 3030
1996 – 3058
1997 – 4587

Temperatures on the Minnesota side of the ND border have also been averaging up to 10 degrees below normal this winter.
http://www.hprcc.unl.edu/products/maps/acis/hprcc/mn/Last3mTDeptHPRCC-MN.png
http://www.hprcc.unl.edu/maps/current/index.php?action=update_daterange&daterange=Month

Note that the entire drainage of the Red River on both sides of the border has been running well below normal. Imagine the devastation that a two degree rise in temperature would bring. No wonder Obama’s teleprompter is concerned.

….
Popper is an interesting guy with some interesting ideas, but there is no need to put his straight jacket on your mind and call it truth.

Personally I found Popper a rather dry read, and I take a position that Thomas Kuhn (of “The Copernican Revolution”, Paradigm Shifts, etc) has a better take.

However, I really like the idea that Science should be Falsifiable. A characteristic that is typically missing in action in the current AGW movement.

Mark

You sure about that? Really? Last chance… OK,

Math, often called “The Queen of the Sciences”…

From: http://en.wikipedia.org/wiki/Mathematics

“The word “mathematics” comes from the Greek μάθημα (máthēma), which means learning, study, science, ”

Or in other words, the very name of mathematics means science…

and

“Carl Friedrich Gauss referred to mathematics as “the Queen of the Sciences”.[21] In the original Latin Regina Scientiarum, as well as in German Königin der Wissenschaften, the word corresponding to science means (field of) knowledge. Indeed, this is also the original meaning in English, and there is no doubt that mathematics is in this sense a science”

Now if you want to subscribe to the belief that math is not popperian so can be excluded from “science” that is your belief, but not very useful. Popper is one person, not God nor the sole authority on thought.

And of course there have been folks who have said that Physics is just applied Mathematics and that Chemistry is just applied Physics; so I don’t think you want to head down the path of trying to show that these are somehow dramatically different forms of thought… (We’ll skip over the assertion that Engineering is just applied Physics, Chemistry, and Mathematics … )

Popper is an interesting guy with some interesting ideas, but there is no need to put his straight jacket on your mind and call it truth.