THAT TIME FORGOT
Station pioneers new river flood plain model
By CARY SHIMEK
No flood plain in the history of the world has been studied as thoroughly as one along the Middle Fork of the Flathead River, which forms the southwest boundary of Glacier National Park.
For the past two years, researchers organized by UM’s Flathead Lake Biological Station have put a stretch of the river’s flood plain under an intense microscope. They are studying the area’s geology, chemistry, vegetation, aquatic organisms, stream flow and more in an effort to gain better understanding of the complex web of water and life — the "shifting habitat mosaic" — that makes up a healthy river ecosystem.
is a whole new way of looking at river ecosystems," says
Jack Stanford, the biological station director and Bierman
Professor of Ecology. "I
think our project is absolutely fundamental to human well- being. It will
teach us how to manage rivers better — to clean themselves
naturally without having to spend tons of money
Flood plains play major roles in controlling the natural purification of rivers and the distribution and abundance of plants and animals within river basins. Stanford contends that if these aquifers are unable to operate naturally, the river ecosystems slowly degenerate. He calls the interplay between life and river systems "biocomplexity."
Researchers are specifically studying the Nyack Flood Plain, a section along the Middle Fork 9 kilometers long and 3 kilometers wide. The flood plain biocomplexity project is funded by a three-year, $2.6 million grant from the National Science Foundation — one of the largest ecology grants ever awarded.
river research focuses on surface water. The biocomplexity
model expands this view by diving underground to include
surface and groundwater interactions and their ecological
implications. Stanford says his model studies the river in
four dimensions — laterally, longi-tudinally, vertically
and over time — to gain the most complete snapshot
"When we first put this out there, it was brand new and changed the whole field of river ecology," he says. "It was revolutionary, but now people embrace it pretty well across the board on the scientific level."
Stanford, who has directed UM's biological research station since 1980, first made waves in the scientific community by discovering that areas beneath rivers actually are pretty happening places: home to stoneflies, salamanders and other unique critters that make up a complex food web. This led him and his colleagues to study how groundwater flows through saturated areas around rivers, especially the subsurface palechannels — areas of preferential flow where water flows faster underground, perhaps because a previous river channel had once been there.
"People don't realize that freshwater doesn't just exist in lakes, ponds and isolated aquifer systems," he says. "Much of it is below the surface, and water that penetrates at the top of the Continental Divide may flow underground for most of its pathway to the ocean."
This unseen part of river systems has been incorporated into the new river model, along with in-depth analysis of the river's erosion and deposition, course and speed, and water clarity.
Stanford says they chose the Nyack Flood Plain for the study because it functions well and is pristine — despite the presence of a railroad and highway running through it — and it's surrounded by wilderness on both sides. Named by railroad workers from Nyack, N.Y., the flood plain also is bounded distinctly by canyons at either end. In addition, most private property on the flood plain isowned by the John Dalimatta family, which has lived in the area for generations and has become a partner in the research effort.
Stanford says the river's virgin flow also is protected into perpetuity by federal reserve water rights that the biological station helped mediate several years ago — something that had never happened before in the United States. This means no dams, no water extraction or other tampering with the river. The Middle Fork should remain a template for what makes a good river forever.
Stanford says 23 researchers are working on the biocomplexity project right now — scientists from the biological station, the main UM campus in Missoula, Glacier National Park and Salish Kootenai College in Pablo. Five undergraduate students also are helping this year.
The fieldwork involves teams that fan out across the flood plain to measure everything from vegetation and animal density to sediment movement and water velocity. Their equipment includes a cabin, a trailer, a slew of sophisticated electronic devices, more than 50 sampling wells and six weather stations.
And new discoveries already have been made.
"We've learned new things about the life cycles of the organisms we knew were there," Stanford says. "They are more complex than we thought, with a lot more morphological variation than we realized — especially things in the groundwater like stoneflies."
They also found the zones of prefer-ential flow in the groundwater are more complex and varied than expected, and that the valley fill, most likely alternating layers of clays and gravel, is deeper than they thought — nearly 150 feet of accumulation in some places.
One key research tool is a spectral-imaging, remote-sensing device that takes pictures of the flood plain from a plane using more than 100 bands. The images enhance what researchers are studying on the ground, and can graphically show changes in the flood plain over time and space.
"For example, we can remotely detect how deep the water is and how fast it's moving," Stanford says. "We also can see how vegetation is distributed across a landscape over time. In simple terms, we also can totally quantify habitat for any organism across the entire landscape of the river using this imagery."
He says the hyper-spectral imager assists with their integrated hydraulic modeling system, which uses geographic information system data to simulate surface and groundwater flows on alluvial flood plains in three dimensions. He says data from the modeling system can be plugged into new software that can create time-lapse movies of Nyack's shifting habitat mosaic.
"And even better, we will be able to fly you through it in three dimensions," Stanford says. "We'll fly you through the habitats, just like a plane, or even fly you through the subsurface palechannels."
He says their research plan calls for delving into precisely how the flood plain transforms and retains nitrogen, phosphorus and carbon. Researchers also will continue studying how rivers naturally cleanse themselves.
"That ability is missing on most of our rivers today because we have changed them so much," Stanford says. "So their natural capacity to clean themselves is compromised or gone, as well as their capacity to produce things such as healthy native fisheries. The main reason the water stays so clean around here is that groundwater circulates through the alluvial gravel in our flood plains. Without these flood plains, Flathead Lake [which the Flathead River flows into] would not be so beautifully clear and clean."
Lessons learned at Nyack about what makes a good river already are being applied around the globe. This spring Stanford took a trip to Norway to help experts there determine why their fishery is becoming depleted.
"They were overfishing," he says, "but they also were channeling water from the top of a mountain straight into their fishery, which had lowered the temperature by 10 degrees centigrade. That's a lot."
Stanford also recently used a Bureau of Reclamation grant to help determine how to restore a fishery on the Yakima River in Washington, where millions of dollars are being spent on the effort. He determined that agriculture was siphoning too much water from the stream.
"We showed them in quantitative terms what it would take," he says, "and, believe it or not, it would take a tunnel through the mountain to subsidize the Yakima with water from the Columbia River. It was very simple: If you want fish, you've got to spend money to bring water from the Columbia. And you mark my words, it's going to happen because it will work."
Stanford says biological station staff soon will hone their river model on another pristine river, this time in Kam-chatka, Russia. Results there will be used to validate what they've learned at Nyack.
"Our overall goal," he says, "is to learn how to help rivers empower themselves."