Sturgeon

Lassoing a Whirlwind: Managing Flow on the Missouri River

By Larry Shepard 

 

When Casey and Jeff asked me to write a blog entry, I was staring at my screen saver which was a picture of a lake sturgeon isolated by the dramatic draw down of the river below Gavins Point dam near Yankton, South Dakota. Along with its more famous cousins, the pallid and shovelnose sturgeons, the lake sturgeon is a prehistoric fish struggling to survive in the altered environment of today’s Missouri River. How this interesting “Jurassic Park” specimen ended up in a pool of water in the Missouri River for folks to gawk at makes for an interesting story. 

Photo courtesy South Dakota Department of Game, Fish and Parks

It’s been an awfully dry summer this year but during the Summer of 2011, the Missouri River basin was saturated from a Spring rain, particularly the upper basin in North Dakota and Montana. Combined with a high snow pack and late season snows in the mountain ranges feeding Great Plains streams, atypical Spring rains produced record amounts of runoff into the six reservoirs managed by the Army Corps of Engineers. 

In an effort to protect the infrastructure of the 1950s and 1960s era constructed dams holding back all this excess precipitation and to prevent dam over-topping and possible catastrophic failure, the Corps released water downstream into the lower basin. Normal releases from Gavins Point (the southernmost dam) in mid- Summer are typically about 32,000 cubic feet per second (cfs), but in July 2011, Gavins passed about 160,000 cfs. That amount of water had never been released through the dam and its impact on the dam structures was unknown. 

http://farm4.static.flickr.com/3185/5833927841_3f68030c93.jpg 

The resulting high water levels innudated the floodplain, displacing residents and damaging crops and property. Levees built to restrict the river to a narrow channel could not hold back the larger volumes of river water, particularly those levees constructed close to the river bank creating ‘pinch points’ for river flow. Repeated failure of several levees, particularly at ‘pinch points’, during multiple high water events has caused the Corps to begin consideration of levee ‘set-backs’ to address an unsustainable levee design which would also open up the floodplain to accommodate more river flow and improve aquatic habitat.  

Photo by Larry Geiger

Fast forward to early 2012, and the volume of releases from dams raised concerns about possible damage to structures, and the Corps determined that close inspection at particular locations to verify condition and assess any damage was necessary. This was the case at Gavins Point near Yankton, South Dakota where the Corps actually closed the spillway in order to allow inspectors to assess damage. That is, no river water flowing through the dam, resulting in an extreme photographic contrast from the Summer of 2011. 

Photo courtesy of South Dakota Department of Game, Fish and Parks

When the dam was closed in May 2012, the reach of the river extending down almost to Sioux City was transformed, exposing natural and man-made features not seen since the dam was finished in 1955. River organisms were stranded, including many mussels, not commonly found in the lower river. 

Photo courtesy of South Dakota Department of Game, Fish and Parks

River scientists know how the lower river’s substrate is dominated by ‘dunes’ of sand which roll and jump along the bottom which was unique to see firsthand. These ‘waves of sand’ create a very dynamic environment for aquatic organisms living in the sediment and coasting above it. It also presents challenges for human engineering to adapt river structures to a moving bottom. 

Photo courtesy of South Dakota Department of Game, Fish and Parks

If you are ever in the vicinity of any of the six big Army Corps dams on the Missouri River, call the Corps office at the dam and see if there’s an available tour of the facility. They are each unique in their design and how they are placed in the ‘natural environment.’ My personal favorite is Fort Peck dam near Glasgow, Montana, the uppermost dam operated by the Corps. It was constructed in the 1930s during the Great Depression and its powerhouse has an ‘art deco’ design. 

Larry Shepard is an environmental scientist in EPA Region 7’s NEPA program reviewing environmental impact statements and environmental assessments primarily focusing on river-related federal projects. Shepard hails from the shores of Beal Slough in Lincoln, Nebraska, which flows to Salt Creek, then to the Platte River, then to the Missouri River and finally to the Mississippi River.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

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Atlantic Sturgeon Enter Endangered Species Protection Program

By Kaitlyn Bendik

Have you ever heard of a fish called the Atlantic Sturgeon? I hadn’t until recently. When I sought out to learn about the different endangered species in the District of Columbia, I learned that this fish can grow to an enormous 14 feet long and weigh up to 800 pounds, but it is also endangered. Who knew such aquatic behemoths lived in rivers and estuaries in the Mid Atlantic Region?

I also learned that the Atlantic sturgeon is an anadromous fish species that can live up to 60 years.  It dwarfs the other two sturgeon species found in eastern North America, and is a benthic or bottom feeder.

Have you ever heard of a fish called the Atlantic Sturgeon?  I hadn’t until recently.  When I googled it, I learned that it can grow to an enormous 18 feet long and weigh over 800 pounds, but is also endangered.  Who knew such aquatic behemoths lived in rivers and estuaries in the Mid Atlantic Region!
The Atlantic sturgeon is an anadromous fish species that can live up to 60 years, and dwarfs the other two sturgeon species found in eastern North America.  They are also benthic or bottom feeders.

Recently, the Atlantic Sturgeon was added to the Endangered Species List in the Chesapeake Bay and four other “distinct population segments.”

So how does a species get listed?  A concerned citizen like you may petition the United States Secretary of the Interior to add a species, which begins a process of deciding whether there’s enough information to prove that a species needs listing.  Likewise, an organization such as the Fish and Wildlife Service or the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service engages in a candidate species process, where a scientific study is conducted to gather data.  When the study concludes a species needs listing, it publishes its findings in the Federal Register for public comment.  Once that process is complete, the species can get its spot on list.

Why is the Atlantic sturgeon on the list?  Historically, this fish was a part of commercial fisheries in the US.  But due to dwindling numbers, in 1998, a harvest moratorium was put on the Atlantic sturgeon.  Despite that action, sturgeon populations are still threatened today.  They get caught inadvertently by fishermen, and in estuaries and rivers, they face habitat degradation and loss due to human activities like dredging, dams, water withdrawals, and development, as well as being hit by ships.

The Atlantic sturgeon species numbers in the Chesapeake Bay have dropped substantially, from about 20,000 breeding females in 1890 throughout the Bay and its tributaries, to less than 300 breeding females that are found in only the James River.  But a comeback is hopefully soon to come with the actions taken to build back its population.

Keeping our water clean will help keep the Atlantic sturgeon around forever. Visit the Chesapeake Bay Program and the Delaware River Basin Commission website for tips on what you can do to help protect the bays and the endangered species that call them home.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

Please share this post. However, please don't change the title or the content. If you do make changes, don't attribute the edited title or content to EPA or the author.