Dam Removals:

Woodlands Lake Dam, Ardsley NY

 

 

Across the country, dam removal projects are leading the way in river restoration. In Irvington, New York, removal of the Woodlands Lake Dam is freeing a section of the Saw Mill River.

In my home county of Westchester, New York, the biggest dam removal project is happening in Ardley, where the Woodlands Lake dam is being demolished in V. E. Macy Park.

In New York, rivers and streams are plugged with thousands of impoundments, big and small. There are more than 7000 dams, and probably many more that haven’t crossed regulators’ radar.

The Woodlands Lake Dam has (or, should I say, had) this in common with so many legacy dams: it articicailly warmed the water that backs up in the impoundment, baking in the summer sun.

 

The stone masonry and concrete dam was built in 1840, and the resulting impoundment has served the county variously as a park, swimming pool, circus location and scenic backdrop for a restaurant (as well as a cameo in the Netflix film, The Irishman).

But the lake created by the dam was only six feet deep at its deepest, and as temperatures in Westchester rise with climate change, the amount of water evaporating off its surface also increased. Removing the dam and storing water in underground aquifers makes water supplies more resilient in an increasingly warmer world.

As a practical matter, the dam was deemed old, obsolete and expensive to maintain.

Once the dam removal process is complete, a pre-engineered bridge will be placed over the river. Pedestrians and cyclists on the Empire State Trail will then have access to V.E. Macy park.

These photos were taken after two days of rain pounded the area, but you can see the  Saw Mill River channel taking shape in the former lake bed.

 

Below, you can see where riffle structures have been built to slow down the rush of water and reduce erosion, all while providing hiding and nesting places for aquatic animals — a far cry from the sluggish, sediment-laden pond of the past.