Working to
Restore Rivers
Since 1984

Video clip credit: MIT Media Lab’s Responsive Environments Group, in collaboration with Living Observatory, at Mass Audubon’s Tidmarsh Wildlife Sanctuary. Used by permission.

Featured Projects


Dam Removal & Fish Passage

Fish passage barriers across the United States are being removed or modified to help fish and wildlife, improve safety and boost recreation. We’ve worked on 150+ dam removals, removed hundreds of culverts, and developed best practices resources for bridge crossings.


Estuary Restoration

Estuaries are dynamic ecosystems where oceans, rivers and human economies converge; they’re also critical to rearing grounds for fish and wildlife and at particular risk to a changing climate. Across the country, we’re reconnecting and restoring these habitats.



Beginning with the daylighting of Tanner Creek in Portland (1992), we’ve been collaborating with urban planners and landscape architects to restore urban streams from coast to coast in the US and abroad.

Thanks to Sonoma Water for sharing this video highlighting more than a decade of working with private landowners and resource agencies in the Dry Creek valley to restore habitat for endangered Coho and Steelhead. To date three miles of Dry Creek have been restored by Sonoma Water with another 3 miles to be constructed in close collaboration with The Army Corps of Engineers.

Inter-Fluve has completed over 2,400 projects. Here’s where we’ve been working.

Today is World Wetlands Day. Instead of talking about how important and beautiful wetlands are, we want to ask you a question. This picture shows a scene that is common in many agricultural areas. A wetland was drained into a ditch, and over time the ditch has started to look and act like a stream. Unlike our other stream restoration projects, there likely was not a channel there in the first place. So, what does it mean to "restore" this area? Does it mean bringing back the wetland and losing the stream? Or does it mean improving instream and riparian habitat as if the stream has always been there?
#wetlands #civilengineering #environmentalscience #environment #climatechange #environmentalengineering #environmental #waterresources #geomorphology #habitat #WorldWetlandsDay

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Here’s a question that we get asked pretty frequently: “Why don’t you just let nature take its course?”

While nature can overcome just about any obstacle placed in front of it, that takes time. So, we use the best science available to move systems towards more sustainable and robust conditions to save species that need those conditions as soon as possible. This can be tricky, because when it comes to aquatic ecosystems, the line between “natural” and “artificial” is blurry. Any surface water that you see is almost always much less “natural” than it seems. Even a scene like this is heavily managed. Following urban growth, developers drained wetlands, built dams, and paved over the ground. These actions increased and exacerbated flooding. In response, a watershed management organization was formed, and a dam was built upstream to control the flow. This story applies to countless streams and rivers across the world, and it has for a very long time.

Historically, in the USA, “managing water resources” has meant ditching, damming, and draining surface water. Over time, a lot of these ditches, dams, and impoundments started to take on the appearance of “natural” streams, waterfalls, and lakes. These systems typically fail to support the full range of ecosystem services that evolved in those locations.

Luckily, as we better understand these systems, there has been a paradigm shift. Instead of confining and diverting streams and rivers, we are seeing riverside communities undertake projects to expand and diversify habitat, improve surface water quality, and support more ecologically appropriate recreational opportunities in their waterways. These projects attempt to restore ecological conditions that, in some cases, have been absent for hundreds of years. This is the sort of work that we support every day.

Returning to the original question: why don’t we just let nature take its course? Emma Maris, in her book Rambunctious Garden, has a possible answer: “We’ve forever altered the Earth, and so now we cannot abandon it to a random fate. It is our duty to manage it." #science #ecology #engineering #civilengineering #environmental #fisheries #environmentalscience

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Camas is one of the most important traditional foods in the Pacific Northwest. Following Euro-American settlement in the area, industrial farming and ranching confined productive camas meadows to just 5% of their original range. Since 2002, we have worked with Tribal communities in the area to develop techniques to reconnect and restore meadow hydrology to improve conditions for camas and other First Foods. #environmental #environmentalimpact #environmentalengineering #waterresources #pacificnorthwest #foodsovereignty ...

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