(Host) The spring floods that have torn up roadways and damaged lakefront property are having an environmental impact as well.
The high water has washed phosphorus and other pollutants downstream into Lake Champlain.
As VPR’s John Dillon reports, climate change could make the problem worse.
(Dillon) The Brown’s River in Essex Center is normally a placid stream that meanders into the Winooski River. This week the Brown’s River and another nearby stream jumped their banks – and inundated a field near David Cota’s house.
(Cota) "Yeah, they’ve been out here spreading liquid manure now for a week."
(Dillon) Cota was looking at a manure spreader whose work was halted by the rising brown water.
(Cota) "Whether or not any of it’s still here or not, I don’t know. It’s probably all headed to Lake Champlain by now this whole valley here being flooded now."
(Dillon) This time of year is hard on the lake, as raging rivers wash animal waste, sewage and soil sediment downstream. The main problem is phosphorus, a nutrient that feeds the algae blooms that plague the lake.
(Smeltzer) "I expect in terms of the amount of phosphorus that comes to Lake Champlain in 2011 we’re going to see a really big chunk of it having come down just in this past week."
(Dillon) Eric Smeltzer is acting manager of the state’s ecosystem restoration program. He says high water can scour out stream banks and that the erosion also contributes to the phosphorus load.
(Smeltzer) "When you get flows this high not only do you have more water carrying phosphorus, you actually have higher phosphorus concentrations in the water because of these processes, the added erosion that’s caused. So it’s almost a double whammy when you look at it that way."
(Dillon) Vermont based its Lake Champlain phosphorus clean up plan on a relatively dry year – 1991. That plan is now being re-written by the Environmental Protection Agency, and it will likely be re-adjusted to reflect the wetter weather of the past decade.
And it may get even wetter. A research study done last year for The Nature Conservancy predicted that climate change will bring more precipitation to the Lake Champlain basin.
Louis Porter of the Conservation Law Foundation says if more rainfall is the new normal, then society will have to adjust the ways it handles water pollution.
(Porter) "And what that means is that we have to have more capacity in all of the prevention system we have to take up water and to deal with large precipitation events. So we need more capacity on farm fields not to have run-off. We need more capacity in our stormwater system to prevent run off there. And we need more waste water plant capacity to handle loads there."
(Dillon) But floods like we’re seeing this spring are natural events, a fact that Mike Kline is quick to point out. Kline is head of the rivers program at the state Agency of Natural resources. He says when a river goes over its banks, the floodplain helps slow the stream’s flow and absorb sediment.
(Kline) "Because they’re the pressure relief valve of the river. If the river can get out on its floodplain, it’s going to be less erosive of those stream banks, which means less pollution into the lake."
(Dillon) Kline says the conflict – and property damage – occurs because people historically have put highways and buildings in places where rivers flood. He says the challenge is to work with communities to protect those floodplain areas.
For VPR News, I’m John Dillon in Montpelier.