First, Ryan Woodard hears from a county official that the recent flooding on Six Mile Creek and elsewhere in Brookings County was of unprecendented intensity:
“I’ve had people on Six Mile Creek that were here in ‘69 say this is the highest they’ve seen it,” Brookings County Emergency Manager Todd Struwe told Brookings County commissioners this week.
“I’ve been here 18 years. I’ve never seen the water this high and I’ve never seen it come this fast” [Ryan Woodard, "Flood's Intensity Unprecedented, County Officials Say," Brookings Register, 2010.10.01].
The Register's John Kubal then turns to Dr. Carter Johnson to discuss the potential impacts of climate change on the Prairie Pothole Region (you know, the great American duck factory we live on). Dr. Johnson discusses a lot of the economic value we get from our prairie wetlands for free—lumber, hunting, water purification. Then Dr. Johnson turns to the economic costs of draining the wetlands, which include more intense floods:
Contrast some of the above with the draining of wetlands and tiling of fields, which leads to water going into small streams and creeks. Johnson noted that people living along the Missouri River saw floods in the 1990s "made worse by the fact that we drained wetlands" [John Kubal, "Could Our Duck Factory Go Dry?" Brookings Register, 2010.10.04].
Dr. Johnson proceeds to other important findings from his climate change research. But it's worth noting that, when it comes to our wetlands, we perhaps need to worry less about Al Gore's jet plane and more about our own digging and physical transformation of our land.
Got high water? Ditch and yard and back forty filling up faster after a big rain than they used to? It could be that, in addition to the heavier rain falling on your land, you're getting heavier drainage from your upstream neighbors. When farmers lay tile under their land and when developers dig up and tile and pave new subdivisions, they remove earth from the prairie-wide filtration system. Water that used to sit and seep out of those acres now comes rushing downstream. That's exactly what's supposed to happen: you plant corn or build a new McMansion, you don't want it sitting in water. But that drainage also shifts your water problem to folks downstream... who have a higher likelihood of seeing their homes and businesses washed away.
Cory, this ties into my whole pine/aspen rant: Aspen stores more surface water. Pine needles absorb heat and shed snowmelt, aspen leaves reflect sunlight in summer and hold snowpacks.
ReplyDeleteAfter aspen stands and other deciduous groves were decimated to build Europe and then in the US, especially at the turn of the last century, pine was allowed to replace it which perpetuate the trophic cascade raising temperatures and exacerbating the rises in sea levels.
Clearing shelterbelts to make way for croplands have contributed to the studies that you quote.
I'll buy that, Larry! All that water has to go somewhere....
ReplyDeleteSay, I seem to recall you talked about the Black Hills originally having much less tree cover. Do grassy hills hold more water than piney hills?
Good question.
ReplyDeleteAt the time when the Hills were less forested there were far more large ungulates accessing water resources. Even at that time, coal was powering the Industrial Revolution in Europe and trees were being cleared to make charcoal most likely starting the cascade.
Remember, fires started by lightning, or even by humans hoping to clear forests for forage, usually burned until snow flew contributing to a more pronounced greenhouse effect, especially in the Northern Hemisphere.