People type engineering with nature and picture a marsh. Sometimes they picture a Corps playbook they can copy onto a local project. Engineering With Nature is neither of those things. It is a U.S. Army Corps of Engineers practice — a method for designing with a living system. It is not the system.
The Corps has used that name since 2010. The living system did not wait for the name. A salt marsh taking energy out of a surge, a floodplain storing a river, a dune holding a shoreline, a reef breaking a wave, a riparian corridor slowing a bank — those were already doing flood, water, and shoreline work. EWN is how a civil-works team can design around that work instead of replacing it with a wall and calling the job done.
what engineering with nature is
Engineering With Nature, often shortened to EWN, is, in the Corps' own words, "the intentional alignment of natural and engineering processes to efficiently and sustainably deliver economic, environmental, and social benefits through collaborative processes."
That sentence is a method. It tells a planner how to combine a living process with an engineered one — sediment, vegetation, and hydrology with a levee, a navigation channel, or a coastal structure — instead of treating those as rival camps. It is especially useful to teams that refuse the false choice between an all-gray project and an all-natural one.
It is also a brand. The Corps publishes an EWN Atlas of implemented projects, runs proving grounds in districts, and hosts a body of technical reports under that name. When a port, a city engineer, or a flood-risk manager says "we did EWN," they usually mean they used that practice on a civil-works alternative.
What they do not mean — or should not mean — is that the marsh, dune, or floodplain is EWN. The living system was already there. The method is how you design with it.
A Corps engineer should hear this as a scope distinction, not a slight. EWN is real practice, field-tested, and federally backed. It is still a way of designing. The object of the design is not the design.
ewn is also a program name
Honesty about the search. EWN is also a program name.
If you typed the phrase because you wanted the Corps program itself — the initiative at the Engineer Research and Development Center, the Atlas, the technical reports — the program lives at the Corps, not here. Start at Engineering With Nature. The Network for Engineering With Nature (N-EWN) is a related partnership between the Corps and the University of Georgia. That is a research and practice network. It is also not the marsh.
This page will not compete with those sites for the program. It will not restate EWN principles as a how-to. The Corps already wrote that. The unpaid job, after the method has a name, is still the living hold.
A project alternative can be "EWN" in a feasibility study and still leave the floodplain unfunded once the construction account closes. Naming the practice does not put an operating line on the living system the practice used.
a method is not the living system
The trap is substitution. A feature on a civil-works sheet, an EWN method, or a project alternative gets treated as the marsh.
Four objects share a hallway:
| what it is | what it is not | |
|---|---|---|
| ewn practice | a Corps method for aligning natural and engineering processes | the marsh, the dune, the floodplain |
| ewn program | a named USACE initiative, atlas, and proving-ground network | a payor for the living hold after the ribbon |
| nnbf | a natural or nature-based feature on a civil-works sheet | the living system the feature points at |
| living system | the floodplain, dune, reef, or riparian corridor already doing the work | a project alternative |
| funded condition | money that keeps that living hold working | a completed EWN project |
An engineer should hear row one as design practice and row four as the asset whose condition determines whether the practice holds. A conservationist should not hear that the marsh's worth is the construction cost of the alternative that copied it. An infrastructure operator should not hear that a living shoreline is just a cheaper wall. The living system does flood, water, and shoreline work. Putting that work on a project sheet does not make the sheet the marsh.
The floodplain, dune, reef, and riparian corridor exist whether or not a civil-works alternative calls them natural infrastructure. Ensurance funds that living hold. It is not the USACE line item.
You might already be thinking: plenty of EWN projects restore the living system, not just mention it. Some do. The ones that do have named a second ticket — care, sediment, monitoring, the condition after construction — and found a payor for it. The ones that don't have treated the method as if it were the marsh. That is the error this distinction is for.
natural infrastructure is the work. ewn is a way in
Natural infrastructure, in the Corps dialect, usually points first to the landscape already doing the work: a wetland storing a surge, a floodplain taking a river, a dune reducing wave energy, a forest holding a slope. EWN is one of the methods a civil-works team uses to design with that landscape.
They are not the same object. Natural infrastructure is a procurement name for a living system already doing flood, water, and shoreline work. EWN is how the Corps learned to put that system on a project sheet without pretending a sheet is a marsh.
This site already has a how-to that owns the head term natural infrastructure. Use how to implement natural infrastructure when the next question is ownership, budgets, monitoring, and stewardship. The definition underneath that how-to is what natural infrastructure actually is. This post stays on the method.
The other dialects — green, nature-based, living — are mapped in four names, one unpaid system. US cities often say green infrastructure when they mean stormwater and urban vegetation. FEMA and the EU often say nature-based solutions for a broader action umbrella. Some cities now say living infrastructure when they mean the care line, not just the planting. This page will not rewrite that map. EWN sits in the USACE room. The living system does not change rooms when the label does.
Canada's Natural Infrastructure Fund is a federal grant. New Zealand's Natural Infrastructure Plan is an Aotearoa Circle plan, not a Crown program. Both reuse the category name. They are not EWN, and they are not the marsh. Name the category. Do not become the brand.
nnbf is the feature language
When the Corps writes a coastal or flood-risk alternative, it often says natural and nature-based features, shortened to NNBF.
A natural feature is formed by natural processes — an existing marsh, dune, reef, or floodplain. A nature-based feature is engineered to mimic those processes — a constructed dune, a restored reef, a living shoreline that combines vegetation with a low structure. The 2015 Corps report on NNBF for coastal resilience is the engineering framework a lot of post-Sandy practice still cites. The April 2024 civil-works memo on incorporating nature-based solutions made that family of measures a formal part of project planning, with EWN as the practice underneath.
A feature is a line item. The floodplain is the living hold. That cut is a feature is not the floodplain. This page only needs the distinction: NNBF is how the method shows up on a sheet. It is still not the marsh.
If the living object you are actually looking at is a tidal edge, you don't have a surge problem. you have a missing marsh is the coastal receipt. If it is inland wet ground, what wetlands actually are is the hydrologic object. Neither post is an EWN manual.
the method does not pay the marsh
Does EWN fund the living system? Construction can fund an EWN alternative. That is not the same as funding the living hold after closeout.
EWN funds a way of designing. Civil-works money then funds a selected alternative — sometimes a hybrid of gray structure and NNBF, sometimes a restoration feature, sometimes a navigation project that places dredged sediment where a marsh can use it. That is real work. It is also a project budget. Project budgets close.
The living system still has a condition after the ribbon. Sediment has to keep arriving. Vegetation has to keep establishing. A floodplain has to stay connected. A dune has to be allowed to move. None of that is automatic because the feasibility study used the EWN name.
ensurance is built to fund that living hold — the named condition of a floodplain, dune, reef, or corridor — not to rebrand a Corps line item. A certificate is specific ensurance: a funded relationship with a named living condition. A coin funds protection more broadly. Neither instrument is EWN, and neither is the marsh.
Our stage, stated plainly. The instruments are live. The volumes are small. A district, a port, or a city that needs a Corps-aligned project today should use the Corps. Nothing here asks you to wait for us to become a substitute EWN program. The distinction is right whether or not our instrument is the one that ends up carrying the second ticket.
If you came here to understand the phrase, you have it. The next useful read is the dialect map, or the definition of the living system the method is about.
frequently asked questions
what is engineering with nature?
Engineering With Nature is the U.S. Army Corps of Engineers' practice of intentionally aligning natural and engineering processes to deliver economic, environmental, and social benefits together. It began as a Corps initiative in 2010. It is a method for designing with a living system. It is not the living system.
is ewn the same as natural infrastructure?
No. Natural infrastructure, in the Corps dialect, names a living system already doing flood, water, or shoreline work. EWN is a method for designing civil works with that system. One is the object. The other is a way of drawing the object onto a project sheet. What natural infrastructure actually is holds the object.
does ewn fund the living system?
No. EWN is a design practice and a named Corps program. Civil-works construction can fund an alternative that uses that practice. The living hold after the ribbon — sediment, vegetation, connection, care — is a different ticket. Completing an EWN project is not the same as paying the marsh to keep working.
what is nnbf?
NNBF means natural and nature-based features. Natural features are formed by natural processes. Nature-based features are engineered to mimic them. Both show up as line items on civil-works sheets. The floodplain, dune, or reef they point at is the living hold. A feature is not the floodplain is that cut.
the series
Five posts. One spine: USACE says natural infrastructure / NNBF. That is a procurement name for a living system already doing flood, water, and shoreline work. A feature on a civil-works sheet is not the marsh. Ensurance funds that living hold. It is not the USACE line item.
- what natural infrastructure actually is — the living system, not a civil-works nickname
- ewn is a method not a marsh — you are here
- a feature is not the floodplain — NNBF is a line item; the floodplain is the living hold
- natural infrastructure investment holds the living part — a ticket can mention nature and still hold concrete
- who pays to keep natural infrastructure working — a living system that does flood work still needs a payor after the ribbon
Adjacent: four names, one unpaid system, how to implement natural infrastructure, living infrastructure is not green paint on a pipe.