By Tim NewcombPosted 01.31.2012 at 11:19 am 19 Comments
In 2010, engineers in the U.S. dismantled 60 dams, helping to reclaim rivers for wildlife. Most of these dams were small, though; removing large ones poses a much bigger challenge. In September, the National Park Service started the largest-ever dam-removal project in the U.S., on the 210-foot (the tallest ever removed) and 108-foot dams on the Elwha River in Olympic National Park in Washington State.
The ongoing flooding along the Mississippi River is the worst the region has seen in recent memory--all three of the river's three major spillways are open at the same time for the first time ever, diverting flood waters from New Orleans and one of America's major fuel refining corridors. Other areas aren't so lucky; water flowing from Louisiana's Morganza spillway (one of the big three) is flooding the Atchafalaya River basin, displacing some 4,000 people. Scenes of inundated towns, rooftops peeking above the water line, are playing out from the upper Midwest to the Gulf of Mexico.
But while the 2011 floods are the worst in years, for many places they're not the worst in that many years. The Big Muddy is topping its banks and barriers more frequently and with greater consequences than flood models tend to predict. There are several reasons for that depending on who you ask, but regardless of whether it's global warming, bad flood modeling, or simple statistical anomaly, one thing is abundantly clear: the mighty Mississippi wants out of the path that humans have determined for it, and it is increasingly finding ways to escape.
Worst-case planning never hurt anybody, and certainly not federal water projects that cost millions of dollars and could be easily undone by climate change and rising sea levels. A new policy now requires the U.S. Army Corps of Engineers to plan for future climate change when designing plans for flood control or other projects.
A huge man-made canal that counteracts coastal erosion
By Carl HoffmanPosted 04.12.2004 at 3:00 pm 0 Comments
What: A huge man-made canal that counteracts coastal erosion
Where: Louisiana coast
Cost: $2 billion â€ $3 billion
Crux: A 1,000-foot-wide, 60-foot-deep channel off the Mississippi River capable of carrying 200,000 cubic feet of water per second over 100 miles.