Flooding? HERE? NO! Where do you live on this MAP?

This is a pieced together collection of maps all of which were created by the Army Corps of Engineers in 1986. It depicts what would happen if the Whittier Narrows Dam failed. The document is in a public library in New Mexico and I borrowed it and scanned the maps and then, put them together in Photoshop. The only alterations were to cut the edges to make a smoother connection between one map and another, and to size it so that I could put them all up on the web in one piece to get the - whole picture of such a disaster.

This is what would happen, according to the Army Corps of Engineers. if the Whittier Narrows Dam fails.... Remember, the Army Corps of Engineers made these maps and it is up to the CITIES around the Dam to not build RIGHT UNDER the Dam. It is also the responsibility of the Corps, the Los Angeles County, that Leases the land in and around the Dam, to not fill the DEBRIS BASIN -> which IS THE NATURAL AREA.... There should be enough room behind the Whittier Narrows Dam to hold ALL OF THE WATER FROM THE FOUR DAMS BEHIND THEM!!! -> Santa Fe Dam + Morris Dam, + the San Gabriel Dam + Cogswell Dam.

If there is STUFF in the Whitter Narrows Natural Area (the Debris Basin is like a reservoir for emergencies like flooding) like lots of Arundo donax or there are buildings (like a Discovery Center with a large parking lot) and the Debris Basin can't hold all the waters from the mountains if the other dams fail or if we have an extraordinary winter storm/s.... then a whole lot of people could loose their lives and property. If the Army Corps of Engineers and/or the Los Angeles County do not take care of the Dam/s - then they are not doing their jobs and we are all at risk.

Where do YOU live in relation to the flood waters????

But here are two close ups that I thought were interesting....

These two clips show that the flooding would first begin by filling up behind the dam and flooding the cities north of the Dam, if, for example, the Santa Fe Dam failed or if there was more water then usual - as in a Hundred Year Flood which could happen next year... or in ten years. Then, if the dam gave way - if the sand under the cement covered berms washed out (see the photos shot in spring of 2010 of the undermined Whittier Narrows

Dam, below) - then all of that water from the mountains and the storm drains from the cities that feed water into the San Gabriel River would gush out to the sea.

Now, let's talk about how well the Whittier Narrows Dam is holding up after all of these years.... It was completed in 1957. Dams have relatively short 'life' spans. The reliability of any dam is all about how the dam was built, what materials were used, what the conditions were/are (earthquakes, high sedimentation, flooding around the dam, piping, design problems, etc.) and how well it is kept up. Like anything, it needs periodic repairs. Has the Whittier Narrows Dam Been repaired? I have not found any references showing repairs or even maintenance. But, I can tell you that it needs repairs NOW!!!

These are the electrical towers (many stories tall) and lines which are near the existing Nature Center. (see Google Maps of Whittier Narrows Nature Center/Dam)

I keep mentioning that the Dam may NEED repairs - IT DOES~!

Do you see the crack with the trees growing out? I could crawl in the crack inside the dam - that is how big this crack is!

I took these pictures from inside and behind the dam this spring 2010. The Whittier Narrows Dam is nothing but sandy dirt and just plain sand piled up like a kid's fort with concrete poured on top. Inside this structure, what is supposed to be big enough to hold all the water from four dams upstream, or when if rains really hard and long, needs to be able to fill up with water. However, the water gets under the concrete and the sand, which is what the Dam is made from, and flushes out in a 'slushy' mud under the concrete 'tent' leaving an empty, hollow top and area that faces the holding area of the Dam. This undermining of the Dam's structure is called 'Piping'. The army Corps of Engineers knows ALL about this and wrote a very extensive paper on the possibility of the Whittier Narrows Dam Failure from piping.... Here is a PDF file of the study...

http://www.vulcanhammer.net/geotechnical/ETL-1110-2-561.pdf

or you can go to this one...

http://140.194.76.129/publications/eng-tech-ltrs/etl1110-2-561/a-g.pdf

or here...

http://140.194.76.129/publications/eng-tech-ltrs/etl1110-2-561/toc.html

Pleasant dreams....

This crack goes all around the Dam!