Project Description

Across the country, aging dams are posing health and safety risks to residents living downstream. They also impede migratory patterns of fish and wildlife, especially on our east and west coasts where migratory fish like salmon journey up to 900 miles to spawn. Few restoration initiatives have as much potential for improving the health of a riverine systems as the removal of dams.

To date, we’ve worked on over 100 dam removal projects including the initial feasibility analysis, design, construction oversight and post-project monitoring. Our work ranges from removal of three centuries-old dams on Massachusetts Mill River, to assisting the California American Water and California Coastal Conservancy in evaluating options for and implementing removal of the 106-foot-tall San Clemente Dam in California, to removing lowhead dams in Florida. We have provided oversight on the removal of 35 of these dams, with several more underway.

Hemlock Dam Removal

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This historic photo shows Hemlock Dam just after construction was completed in 1935.

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Our team prepares to remove Hemlock Dam 76 years later.

The 26-foot tall dam and its reservoir had inadequate fish passage, interrupted sediment transport, and elevated summer stream temperatures in its reservoir–temperatures that can be fatal to threatened Lower Columbia River Steelhead.

The reconstructed stream channel emulates natural systems.

Construction involved restoring 2,000 feet of the pre-dam reservoir to a dynamic river that followed its historic channel. Photo in 2016, 7 year after removal.

Mill River Dam Removals

Hopewell Mills spillway before it was removed.

With the spillway gone, Mill River now meanders through a floodplain. To unearth the historic floodplain, over 200 years of sand and silt were excavated.

A partial failure of the Whittenton Mill Dam (pictured here) nearly flooded downtown Taunton during a storm in 2005.

One year after Whittenton Mill Dam was removed, plantings on the new floodplain are taking hold.

Over two dozen sea lamprey were observed spawning in the newly constructed channel at the Hopewell Mills site soon after removal. Photo: Mike Trainor, Mass Division of Marine Fisheries

Simkins Dam Removal

The removal of the 10-foot-high and 200-foot-wide Simkins Dam in Maryland is part of a larger project to remove all four dams along 175 miles of the Patapsco River and restore habitat to herring, shad, and eel.

Site of the former Simkins Dam.

Brown Bridge Dam Removal

We completed conceptual and final design documents, and provided full construction oversight for the sediment management and channel restoration at the Brown Bridge dam (1500’ long and 40’ tall).

Brown Bridge was the first and largest of three dams to be removed on the Boardman River, and one of the largest removed in the state of Michigan.

San Clemente Dam Removal

Inter-Fluve provided assistance to California American Water and California Coastal Conservancy in their evaluation of options for and implementing the removal the 106-foot tall San Clemente Dam. Photo: WSC and California American Water

Condit Dam Removal

We developed the sediment management plan for breaching the 95-year-old, 125-foot-high Condit Dam located in southern Washington State.

Condit Dam was breached in 2011, revealing tree stumps 98 years after the area was logged. Photo: PacifiCorp