Which rivers are designated critical habitat.

No. A critical habitat designation does not close land or water, does not create a refuge, and places no restriction whatever on private activity that involves no federal agency. What it does is trigger section 7 of the Endangered Species Act for FEDERAL actions — a federal permit, federal funding, or work by a federal agency. In that case the acting agency consults with the U.S. Fish & Wildlife Service or NOAA Fisheries about whether the action would destroy or adversely modify the designated habitat. Most consultations conclude without the project being stopped. If your work needs a Clean Water Act section 404 permit, a hydropower licence, or federal money, a designation is something to plan around early; if it involves no federal nexus at all, the designation itself does not reach it.

No, and this is the most common and most expensive misreading of this map. Critical habitat is designated by rulemaking for only a fraction of listed species, and often years after the species is listed — many listed species have no designated critical habitat anywhere at all. Section 7 consultation is triggered by a federal action that may affect a LISTED SPECIES, whether or not designated habitat is present. So an empty map means one narrow thing: no critical habitat has been designated here. It is not a finding that no listed species is present, and it is not a clearance. The agency’s own IPaC screening tool is where a species list for a specific location comes from.

Because the two agencies map them differently, and the difference falls almost exactly along the species split. NOAA Fisheries publishes critical habitat for salmon, steelhead, green sturgeon and eulachon as LINEWORK following stream reaches — the designation is the river itself. USFWS designations for terrestrial species, lakes and estuaries are polygons. This matters more than it sounds: a reading of this dataset that took only the polygons would report no critical habitat across most of the Columbia and Sacramento basins, which is the single largest concentration of river critical habitat in the country. Both geometries are drawn here.

They are three unrelated things that this map deliberately keeps apart. Critical habitat is an Endangered Species Act designation about a particular listed species — it can sit on private land, and it confers no ownership or access change. A National Wildlife Refuge is federally owned land managed by USFWS. “Protected land” on this page means anything inventoried in the USGS Protected Areas Database, which includes national forests open to logging, BLM grazing allotments and private conservation easements. A stretch of river can be all three, any one, or none, and the three answers have no bearing on each other.

It is what the land is actually managed FOR, and it is the reason this page does not publish a single “protected” number. GAP 1 and 2 land is managed for biodiversity, with permanent protection. GAP 3 land is permanently protected from conversion but managed for multiple use — that category includes land open to logging, grazing and mineral extraction. GAP 4 is inventoried land with no known conservation mandate at all. Collapsing these into one figure is the most common overstatement made with PAD-US: a state can be a third “protected” and have very little of it managed for nature.

A final designation has been through rulemaking and is in force; it triggers section 7 consultation. Proposed critical habitat has been published for comment and is not yet in force; a federal action affecting it triggers a conference, which is a lighter and largely advisory process. They are drawn differently on this map — proposals are hatched — and counted separately in every figure on the page, because folding them together would either overstate an obligation that does not exist yet or understate one that does.

The designation layer is rebuilt monthly from the USFWS and NOAA Fisheries geospatial services, and in most months it is unchanged — critical habitat moves by rulemaking, on a calendar of months to years, not by observation. The protected-area figures come from the USGS PAD-US edition named on the page, which USGS republishes roughly annually. That is genuinely different from the rest of the maps on this site, most of which are hourly or daily; this dataset simply does not move that fast, and a faster refresh would redraw identical boundaries.

The designations are harvested from the U.S. Fish & Wildlife Service and NOAA Fisheries public geospatial services — the same services the agencies’ own mappers read — and republished by Driftwise as static files. The protected-area rollups come from the USGS Protected Areas Database. We re-serve this data; we do not author it, and we are not the consulting agency. Boundaries here are simplified for web drawing, so for anything that matters the agency’s own mapper and the Federal Register rule that established the unit are authoritative.

Arithmetic. PAD-US publishes roughly 440,000 polygons for the United States — far more than a browser can reasonably be asked to load, and orders of magnitude larger than every other layer on this site combined. So protected land is reported as acreage by managing authority and by GAP status, which is the form the question “who manages the land” is usually asked in anyway. The designations number in the low thousands and keep their geometry, because for those the boundary is the fact.

Yes. ESA critical habitat and protected-area management are among more than a dozen federal inputs Driftwise resolves onto the specific waters a customer is responsible for, alongside USGS gauge readings, the National Water Model, drought classification, NOAA flood forecasts, wildfire proximity and EPA water quality assessments. In the product a designation is joined to the individual reaches and access points a crew manages — including the linear designations that a polygon-only screen would miss — so it becomes a factor in planning work rather than a map somebody has to remember to check.