[Flooding on the Missouri River, up and downstream from Hamburg, Iowa. The distinct spray pattern produced by burst levees is visible in at least three locations, while the raised outline of the emergency Ditch 6 levee can be seen on the western edge of Hamburg, protecting the city from the insistent floodwaters. Imagery captured by […]
[A dike field in the Mississippi River near Greenfield, Mississippi; via bing maps.] In the Mississippi River, dike fields are constructed in order to direct the river’s flow to a central channel, scouring it and reducing the need for dredging. Though their primary purpose is to thus maintain navigability for shipping, dike fields tend, as […]
As I’m gathering projects, proposals, practices, and places to be covered before I wrap up our summer flood-blogging extravaganza (which I expect to do by the end of the month), I thought it worth looking back at a handful of notable posts from mammoth‘s past that concerned flooding. Hopefully some of these, since they are […]
[The Waterways Experiment Station, in Vicksburg, Mississippi, is currently the home of the Army Corp’s Coastal and Hydraulics Laboratory. (It also is the entity which operated the Mississippi Basin Model, and the research into flood control and river hydrology which was once conducted physically on that model and its sister models is now conducted, primarily […]
The San Francisco Bay Model was, like the Mississippi Basin Model, built by the Army Corps of Engineers to study the flow of water — in this case, simulating “the rise and fall of tide, flow, and currents of water, mixing of salt and fresh water, and… trends in sediment movement”, permitting the study of […]
[The Mississippi River Basin Model today, via Bing Maps.] At Places, Kristi Dykema Cheramie writes about the one of Mississippi flood control’s most fantastical landscapes, the Basin Model — “a 200-acre working hydraulic model [replicating] the Mississippi River and its major tributaries — the Tennessee, Arkansas and Missouri Rivers”, on a small tract of land […]
[Cahokia mounds, photographed by Ira Block for National Geographic; the mound immediately above is “Monk’s Mound”, the largest (ten stories tall) of the Cahokia mounds.] Around a month ago, FASLANYC ran an excellent post that described the Mississippian mound culture as a potential source of inspiration for a reconsidered Louisiana delta urbanism. In the post, […]
[Detonation at the Birds Point inflow crevasse, during the night of 2 May 2011.] As sand boils appeared in Cairo, the swollen rivers continued to rise. The city was under mandatory evacuation orders, and the flood gauge was expected to reach 63 feet — not high enough to over-top the city’s levees, but high enough […]
[The breach in Missouri River Levee 575, on June 14.] The breach at Hamburg — mentioned a few posts back — began with a “sand boil”, a geotechnical phenomenon shared by earthquakes and floods, in which subterranean water pressure becomes so strong that ground water erupts, typically bubbling like a gentle geyser, and bringing soil […]
[Flooding on the Indus river around Hyderbad, Pakistan, 19 August 2010; image via NASA Earth Observatory.] At Weather Underground, Jeff Masters reflects on the extreme weather of 2010 — which included monsoon flooding in China, the Pakistani floods (the most expensive disaster in Pakistan’s history), the Queensland flood (Australia’s most expensive natural disaster), Colombia’s record […]
[Just north of the Missouri River, another, smaller river has been smashing flood records, propelled by the same combination of snow pack and heavy rains. In the oil boomtown of Minot, North Dakota, the Souris River (French for “mouse”, which has produced the local nickname “the Mouse”) has reached thirteen feet over flood stage — […]
[A dredger at work in one of Fort Peck Dam’s borrow pits; photographer unknown. (Fort Peck, you will recall, was the first of the six major dams on the Missouri to be built.) The dredgers, pontoon boats, and booster barges used in the pumping of fill material from upstream borrow pits to the Fort Peck […]
[The “Ditch 6” levee at Hamburg, Iowa; photographed by the Army Corps of Engineers on June 16. Following the breach of levee 575 which prompted the evacuation orders for southern Hamburg, the Army Corps “immediately underwent further construction to raise the elevation of Ditch 6 levee”; the plastic sheeting protects the soft earth of the […]
[I’ll be updating this atlas as I continue to post on floods; for now, there are two categories — blue, for Missouri floods, and yellow, for historical Mississippi floods.]
[Fort Peck Lake (top), Spillway (middle) and Dam (above), in northeast Montana; built between 1933 and 1940, Fort Peck is the world’s largest “hydraulically-filled” dam, which means that it was constructed by dredging suspended sediment from borrow pits and pumping it to discharge pipes at the dam site, where it settles onto the embankment. (This […]
[False-color satellite imagery of flooding along the Missouri River near Hamburg, Iowa: “On June 19, 2011, the AHPS reported, the Missouri crested slightly above the record level set for Brownville [Nebraska, about 15 miles downstream from Hamburg] in 1993. The record level was 44.3 feet (13.5 meters), and on June 19, the river briefly reached […]
[The “project design flood” is the maximum flood that the Army Corps of Engineers has engineered the Mississippi River’s flood control structures to accommodate; the image here (via America’s Wetland and Loyola University) shows those flows in cubic feet per second. I’ve been slow to link (though, as promised, the flood blogging is going to pick […]
In NASA Earth Observatory’s latest image of the Mississippi River Valley, floodwaters from this spring’s historic flooding — “the floodwaters have been the highest on record at more than half of the gauges along the [levees] between Missouri and Louisiana” — are receding, and the river crested back on the 31st of May at Morgan […]
[Cubit’s Gap, Louisiana] FASLANYC reports on the Mississippi as a “land-making machine”, vividly illustrated by the case of Cubit’s Gap: “…let’s consider the case of Cubit’s Gap, a major subdelta of the [Mississippi]. The gap formed in 1862 after an oyster fisherman (Cubit) and his daughters excavated a small ditch in the natural levee between […]
[A NASA visualization of the 1993 summer wind patterns that caused that year’s Mississippi floods: “The arrows indicate wind trajectories, while color indicates wind height. The length of a line equates to wind speed (stronger winds get longer lines). Black arrows trace the low-altitude winds that carry moisture, the winds most relevant to the 1988 […]
