The second of a two-part series. Click here for the first part.
The northern Great Plains doesn't attract much attention when it comes to climate change. It's not besieged by rising seas like the East Coast or threatened by prolonged drought and wildfires like the far West. Webbed with rivers, the region is the heart of North America's crop production, and its problem is that it's getting wetter.
The prime example of this growing issue is the Red River. It is the northernmost tributary of the Mississippi River system. While that generally runs south, the Red River runs north from the border of North Dakota and Minnesota to Lake Winnipeg in Manitoba.
The river, experts say, is "flashier" than most watersheds. With spring snowmelt and heavy rains pushing it north to still-icebound waters in Canada, the Red River has a habit of backing up and creating floods farther south. And as the climate changes, snowmelt is expected to come heavier and rainfall is expected to become heavier, potentially giving nearby residents new meaning to what is meant by flashy.
Recent flooding has already caused billions of dollars of damage on both sides of the border in recent years, and a flashier Red River could send the damage bills much higher.
This added soaking of the northern plains affects both countries that share the Red River. The impacts may be extreme, but they won't be equal, and that could spawn more cross-boundary water-management headaches. The more recent ones have already led Dennis Todey, the state climatologist for South Dakota, to call the Red River the region's "poster child" for the effects of climate change.
In 2010, for example, heavy rainfall led to one of the worst floods in the watershed's history. And in 2011, further rainfall in North Dakota and Minnesota and an ice jam upstream led to a one-in-300-year flood in Winnipeg, Manitoba, the largest city in the Red River Basin.
This conundrum has some officials concerned that existing flood control infrastructure between the two countries may not be able to cope with what's expected next.
"There needs to be discussions about looking at extreme events. How do we adapt and mitigate these events?" Todey asked. "Do we try to move people out of there? Do we require them to have flood insurance? Do we build structures to protect them?"
New problem, old plans, 'cumbersome' process
The International Joint Commission (IJC) is a binational body tasked with mediating water management discussions between U.S. and Canadian governments. Across the border, the IJC follows the guidelines of the 1909 Boundary Waters Treaty -- which was drawn up by the two countries to specifically manage the Milk River Basin across Montana and Alberta -- but there is no formal agreement between the governments over how the Red River Basin should be managed.
IJC involvement in different cross-border basins "really varies on a case-by-case basis," said Frank Bevacqua, a public affairs officer at the IJC. A major factor in how much regulation a watershed requires is how much infrastructure is built to manage water flows and flooding.
The Red River has no large-scale flood control structures. There is a diversion around Fargo, N.D., designed to head off floodwaters. There are other diversions around Winnipeg, but in the case of the 2011 floods, the diversions were not enough to prevent major flooding.
Earlier this year, farmland outside Winnipeg was almost intentionally flooded to spare Winnipeg after more heavy snowmelt and spring rains almost burst the banks of the Red River and its northern tributaries (ClimateWire, July 10).
The Red River Commission is a regional organization that manages the watershed on a local level, formed after historic flooding along the river in 1997. The basin covers North Dakota, Minnesota and Manitoba, and the commission is designed to facilitate discussion among the three jurisdictions on issues from flooding to water quality and invasive species.
The commission is working on a long-term flood management plan, according to Jeff Lewis, assistant executive director for the commission, with the goal of reducing the impact of a 100-year flood by 20 percent.
"That process of [going through] the IJC, through state departments, is sort of long and cumbersome. When you're working at that higher level of diplomacy, it usually takes longer for things to get done," Lewis said.
The Red River Commission is working to build flood storage units on the U.S. side of the border. The Manitoba government is building dikes and diversions to protect its cities.
"Other than getting the involvement and blessing of that high of a level, most of the things we want to try and accomplish don't really have to go through IJC," Lewis added.
Farmers increase flooding and pollution
Flowing along with the potentially "flashier" Red River is a dramatic change in land use that's affecting not only the basin's chances of flooding, but also the quality of the water downstream.
Lake Winnipeg, in particular, is experiencing severe pollution as a result of agricultural nutrients washing into the river and being carried upstream, in large part because many farmers have turned to tiling water conduits, which can improve their crop yields. Crops require specific soil moistures to thrive, and too much subsurface water can prevent root development and inhibit crop growth. More farmers have been installing subsurface tiling to remove excess water.
"We're getting additional flow in the rivers from the tiling activity and on top of what we may be getting with climate change," Lewis said.
According to Rob Sip, an environmental policy specialist at the Minnesota Department of Agriculture, most of the tiling in the Red River Basin has been installed in the last five to seven years. Officials on both sides of the border are now working to try to promote different land use practices and reduce the volume of nitrates infiltrating the river.
"A number of agencies and partners have come together to develop a nutrient management plan specific for the Red River Basin," Sip said.
Tiling could also potentially help farmers hold back more water and reduce runoff in the future by diverting it into their own storage tanks, he added, helping to limit flooding and improve downstream water quality.
"One thing that people are very aware of now is when there are rainfall events or spring storms or even winter snowfall events, they are much more extreme than they used to be," he said. "So it comes down to how you manage for those extremes."
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