(Host) One of the worst pollution problems in Lake Champlain is also the hardest to control. Experts agree that stormwater is one of the main culprits for the tons of silt and nutrients that have harmed the big lake. But controlling stormwater presents difficult scientific and legal challenges.
VPR’s John Dillon reports:
(Dillon) A heavy rain washes the street. The water rushes downhill and toward Lake Champlain. Along the way, it picks up a nasty mix of sediment, fertilizer, grease and gasoline.
The rain has stopped by the time University of Vermont scientist Al McIntosh checks on a small stream near Spear Street in South Burlington.
(McIntosh) “So I come here during dry weather and during wet weather and I monitor the stream for phosphorus, E coli and occasionally for toxics as well.”
(Dillon) After a heavy rain, the tiny stream can swell from 16 inches wide to almost 16 feet. McIntosh says his students who sampled the water recently had to rope themselves to a nearby road sign to avoid being swept away.
The little tributary flows into Potash Brook, a stream that’s heavily damaged by stormwater. This branch catches the run off from a nearby shopping mall and Interstate 89. When the rain hits all that pavement, it doesn’t soak in. It overpowers the stream.
(McIntosh) “So the increase in volume can be amazing because the water is passing very quickly over this pavement into this little tributary. With that flow of course is more phosphorus, more nitrogen, suspended sediments and more bacteria.”
(Dillon) And unless the stormwater is slowed down or diverted into holding ponds, all that stuff ends up in Lake Champlain. Everyone agrees that stormwater is a huge problem for the big lake. What they can’t agree on is how to fix it.
(Douglas) “Rather than appeal to the Supreme Court, I’ve asked my legislative team and the Agency of Natural Resources to prepare a legislative solution….”
(Dillon) A frustrated Governor Jim Douglas said last month that he wants lawmakers to step into the legal and scientific debate over stormwater. Douglas says the Legislature has to act because of a recent ruling by the Water Resources Board that rejected the Agency of Natural Resource’s solution to stormwater pollution for four streams in Chittenden County.
The board said the agency’s plans would not do enough to clean up the streams within the five years that the law requires. Agency of Natural Resources Secretary Elizabeth McLain says there’s just too much uncertainty to show that the streams would improve over five years. For example, she says in some cases the stream banks themselves are eroding, and that sediment contributes to water quality violations.
(McLain) “We cannot go ahead based upon our plans and guarantee that there will be compliance with water quality standards in five years. There are too many uncontrollables, too many variables – principally the streams themselves.”
(Dillon) Back on Potash Brook, UVM researcher Al McIntosh says he has some sympathy for McLain’s position.
We’re downstream from Spear Street now in woods owned by UVM. Here, the main stem of Potash Brook looks almost like a pristine Vermont trout stream. But nearby highways and acres of parking lots have harmed the stream life. McIntosh says it’s often difficult to identify the specific pollution source.
(McIntosh) “So one of the challenges that biologists, state regulators and everyone else has is, if you find an impact how do you find out where is it coming from? Is it Trib 3? Is it Trib 7? And that becomes a very challenging scientific question: where do you go in the watershed to find the source of the problem? And what can you do to fix it?”
(Dillon) Environmentalists say it’s not all that complicated. Chris Kilian of the Conservation Law Foundation says the state knows who owns the sites where much of the pollution comes from. He says what it really comes down to is money.
(Kilian) “Commercial interests that are discharging into these watersheds don’t want to pay. They pay don’t want to pay for the clean up. The solution to these problems is not weakening our standards or giving polluters more time to pollute. It’s focusing resources on cleaning these watersheds up. And it can be done.”
(Dillon) Most experts say that storm water can be treated effectively with ponds or manmade wetlands that trap the heavy flow before it reaches the stream.
For Vermont Public Radio, I’m John Dillon.