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Slowing Down the River

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Heather Murphy stands amid debris cleaned up in a Plainfield floodplain area after the flood of July 2023. Photo courtesy of the Friends of the Winooski River.
By Michele Braun

We all know that water flows downhill; young children experiment with this by engineering in rainy playgrounds, digging ditches to send the water one way or another. Water flowing downhill is essentially what defines a ‘watershed’ — the area where rainfall flows from higher elevations to lower until it reaches a stream or river. After the flood last summer, a lot of people in Montpelier began giving more thought to where all the water had come from in town. What’s the area upstream of the city that sent us so much water? 

The accompanying map shows the entire watershed area for the Winooski River. The area upstream of Montpelier to the northeast includes Cabot, Marshfield, Plainfield, Calais, and East Montpelier, which send rainfall to the Kingsbury Branch and the Winooski River. 

To the southeast of Montpelier, we have Washington, Williamstown, Brookfield, and Barre, which send their rainfall to Montpelier via the Jail Branch and the Stevens Branch. The Stevens Branch flows through downtown Barre and joins the Winooski near the Route 2/Route 302 roundabout. 

When the Friends of the Winooski River (FWR) considers how best to reduce flooding in Montpelier, the organization looks at this whole area upstream of the city to find ways to slow down the flow of heavy rain storms coming into town. 

In the flooding last year, the floodplain forests in Plainfield were incredibly effective at capturing sediment and debris: the Friends of the Winooski coordinated the cleanup of 6.5 tons of man-made material from Plainfield that settled in floodplains, especially where there was mature forest, such as along Recreation Field Road. That is all junk that did not reach Montpelier. 

The Friends of the Winooski measured the sediment deposited in Marshfield’s Martin Bridge Park and found that on this floodplain area where the river was able to spread out, it left more than 3,000 cubic yards of material behind. That’s two dump truck loads of river sediment that did not reach Montpelier. 

In the last 15 years, the Friends of the Winooski has planted over 40,000 trees along streams throughout the watershed — including on six Montpelier properties — to restore floodplain forest so it can provide its many beneficial functions. The Friends has completed a floodplain restoration project — Dog River Park in Northfield — that proved successful at reducing flood elevation in the July 2023 flood. Most of the land in the Winooski watershed is privately owned, so all this work relies on informed and engaged landowners. 

Many landowners in Montpelier have been taking steps to learn more about managing their land for a clean, healthy, and resilient environment. When rain falls on our roofs, driveways, and lawns, it moves very quickly downhill toward the streams and rivers. It’s hard to follow the path of the rain from your roof to the North Branch or the Winooski because it may flow into a catch basin, and travel through the underground stormwater pipes to get to the river. We walk through the city every day unaware of the streams flowing beneath our feet toward the rivers. 

Twenty Montpelier residents have taken advantage of the Friends of the Winooski’s free Storm Smart consultations to learn how to manage rainfall on their property to reduce negative impacts. The Montpelier Conservation Commission and the North Branch Nature Center have applied for funding to facilitate neighborhood-scale conversations about where rainfall is flowing and what landowners can do to help the rain slow down, spread out, and sink in, to reduce the volume and speed of water flowing into our vulnerable downtown. 

There has also been more attention to dams in the past year. In the Winooski River watershed, there are only three dams that hold back floodwaters: the East Barre, Wrightsville, and Waterbury reservoirs. They are the only dams with storage capacity behind them waiting to fill with rain.

Meanwhile, there are over a hundred old dams in the watershed that make nearby flood levels higher, and that no longer serve their original purposes. Many dams were constructed to operate mill machinery, to generate electricity, or to form ponds for drinking water or recreation. 

The Friends of the Winooski River is working on removing six of these problematic structures around the watershed. The Vermont River Conservancy is focused on four in Montpelier, including the Bailey dam near Shaw’s. Removing the dams — and the accumulated sediment backed up behind them — will lower nearby flood levels and make the rivers cleaner, healthier, and more resilient. 

The challenges of managing rivers with a lot of human development along them are multi-faceted and complex, and so are the solutions. The more people who take an interest in understanding how our rivers function and in understanding the role of their land and buildings in the landscape, the more support there will be for implementing the various solutions needed to reduce the speed and amount of water reaching our beloved downtown. 

Michele Braun is the executive director of the Friends of the Winooski River.


What You Can Do: Slow Down the Rain Runoff

  • Direct roof downspouts to rain barrels or into a garden where water can spread out.
  • Collect rainfall in rain gardens or swales so it takes longer to reach our rivers. 
  • Reduce the size of lawns: meadows, gardens, and woody plants (shrubs and trees) will slow rain. 
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