Managing the Missouri
The Missouri River Reservoir System is the largest reservoir system in North America. Management of the system is complicated by multiple and diverse interest groups and applicable laws.
Interest groups represent irrigation, flood risk, hydropower, recreation, water supply, navigation, fish and wildlife, cultural resources, and commercial sand and gravel dredging.
One of the applicable laws is the Endangered Species Act of 1973, which provides for the conservation of threatened or endangered species and their habitats. The U.S. Fish and Wildlife Service maintains the official list of threatened and endangered species.
Three listed species live in the Missouri River basin: the endangered pallid sturgeon, the endangered least tern, and the threatened piping plover.
The Missouri River runs over 2,300 miles from Three Forks, Montana, where the Gallatin River, the Madison River, and the Jefferson River join as its headwaters. It drains into the Mississippi River north of St. Louis, Missouri.
It was once “the turbid, rapid stream — the Missouri.” That is how John Jay Audubon described it in 1843.
Now the Missouri River is slowed at six major reservoirs behind dams. Fort Peck Lake and Fort Peck Dam are on the river in Montana. North Dakota has Lake Sakakawea behind Garrison Dam and Lake Oahe behind Oahe Dam. In South Dakota, there are Lake Sharpe at Big Bend Dam and Lake Francis Case at Fort Randall Dam. South Dakota and Nebraska share both Lewis and Clark Lake and Gavins Point Dam.
This large reservoir system affects the three listed species.
Maintained by the US Army Corps of Engineers, this reservoir system has the capacity to store 72.4 million acre-feet of water. An acre foot of water can cover one acre to a depth of one foot. Precipitation, snowmelt, hydrology, basin and agriculture drainage, and resource uses influence decisions about the level of each reservoir.
How can the Corps of Engineers operate the reservoir system without jeopardizing the listed species? To answer that, the Corps of Engineers, in cooperation with the Fish and Wildlife Service, has prepared a massive Draft Missouri River Recovery Management Plan and Environmental Impact Statement with supplemental materials.
The plan offers six alternatives intended to help the three species.
Alternative 1 is the congressionally mandated no-action alternative. This do-nothing option is not acceptable as the Corps of Engineers recognizes demonstrated needs for management plans “informed by the best available science,” including new scientific information about the species and their habitats.
The remaining options provide for variable amounts of mechanical construction of emergent sandbar habitant for the plovers and terns. The different water flow releases of the alternatives account for the variable amounts of mechanical sandbar construction.
The five remaining alternatives also include managing reservoir releases during nesting season to reduce the chances of rising water taking nests, eggs, or chicks of the plovers and terns.
Furthermore the five alternatives support hatchery propagation of the pallid sturgeon and monitoring sturgeon population, as well as construction of early-life stage habitat in the lower river. These are good basic measures.
But beyond that, where are provisions for designation of critical habitat for the endangered pallid sturgeon; for unbalanced reservoirs to address the situation at a particular reservoir; for the application of the best science currently available?
Habitat loss, fishing and caviar harvesting, entrainment and watercraft propellers, contaminants, hybridization, invasive species, and iridovirus all threaten the endangered pallid sturgeon. None of the alternatives provide adequate response. The pallid sturgeon requires shallow-water habitat.
Designation of critical habitat is necessary! The Corps of Engineers seemingly acknowledges that with the phrase “avoid jeopardizing the continued existence of pallid sturgeon or its critical habitats” in the accompanying Draft Science and Adaptive Management Plan.
Perhaps having unbalanced reservoirs as a management tool in the Missouri River Mainstem Reservoir System Master Water Control Manual is adequate, but perhaps not.
To say that Alternative 2 — following the U.S. Fish and Wildlife Service’s 2003 Biological Opinion projected actions — is the best alternative presented, and it is clearly is, is not to say that Alternative 2 is adequate.
A lot of science has been done since 2003, and that science should inform policy and practice.
The Draft Missouri River Recovery Management Plan and Environmental Impact Statement and supplemental documents are available online at moriverrecovery.usace.army.mil. Public comments are accepted through April 24.