Critical habitat in Delaware.

Designates critical habitat for anadromous and marine species — salmon, steelhead, green sturgeon and eulachon. These are the designations most river corridors run through, and they are the ones mapped as linework rather than as areas.

Find your NOAA Fisheries regional office →

Designates critical habitat for terrestrial and freshwater species — mussels, darters, amphibians, plants and riparian birds.

Find your USFWS Ecological Services field office →

415k acres

Summed across designations, so a wilderness inside a national forest is counted in both. A count of inventoried holdings, not a measure of how much of Delaware is protected.

Most acreage managed by: State.

126k acres

GAP 1 and 2 only. The remainder of the total above is largely GAP 3 — permanently protected from conversion, and open to logging, grazing and mineral extraction. Reported apart, because one combined figure would let multiple-use land read as a refuge.

• Federal96k acres
• State219k acres
• Local government62k acres
• Private (NGO or easement)33k acres
• Jointly managed5,403 acres

• GAP 1 — managed for biodiversity, natural disturbance9,538 acres
• GAP 2 — managed for biodiversity, suppressed disturbance117k acres
• GAP 3 — multiple use141k acres
• GAP 4 — no known mandate148k acres

A river drawn with nothing on it means one thing: no critical habitat is designated there. It is not a finding that no listed species is present, that no other protection applies, or that a project there needs no review. Section 7 consultation attaches to federal actions that may affect a listed species — not only to actions inside designated habitat.

Critical habitat is designated by rulemaking, for a fraction of listed species, and often years after listing. Many listed species have no designated critical habitat anywhere. So this map shows where the federal government has drawn a boundary — not where the animals and plants actually are.

Salmon, steelhead, green sturgeon and eulachon critical habitat is published as linework along stream reaches rather than as areas. A reading of this dataset that took only the polygons would report no critical habitat across most of the Columbia and Sacramento basins. Both geometries are drawn here, and the legend says which you are looking at.

NOAA Fisheries designates critical habitat for anadromous and marine species — the salmon and steelhead most river corridors run through — while the U.S. Fish & Wildlife Service covers terrestrial and freshwater species. They are different offices with different consultation processes. Every unit here names the agency that designated it, because calling the wrong one costs weeks.

Proposed critical habitat is drawn hatched and is counted separately throughout. A final designation triggers section 7 consultation; a proposal triggers a conference, which is a different and lighter obligation. Neither figure on this page silently includes the other.

The protected-area figures come from USGS PAD-US, which inventories holdings by what they are managed for. GAP 1 and 2 land is managed for biodiversity. GAP 3 land is permanently protected from conversion but permits logging, grazing and mineral extraction, and GAP 4 has no known conservation mandate at all. This page reports them apart, because a single “protected” figure would let a multiple-use timber unit read as a refuge.

PAD-US records a holding once per designation, so a wilderness inside a national forest is counted in both. Summed nationally that comes to more acres than the United States has land, and in Alaska, Utah, Idaho and Nevada the total exceeds the state’s own area. The figures here are therefore a count of inventoried holdings, not a measure of how much land is protected — which is why no percentage of a state is published alongside them.

Driftwise re-serves the federal record; we do not author it and we are not the consulting agency. Boundaries are simplified for drawing, and the designating agency’s own mapper and the Federal Register rule are authoritative for any decision that matters.

Nobody at Driftwise can tell you what a designation means for your project in Delaware. The designating agency can, and which one depends on the species rather than on where you are.

• Salmon, steelhead, sturgeon and other anadromous species —your NOAA Fisheries regional office →
• Freshwater mussels, fish, amphibians, plants and riparian birds —your USFWS Ecological Services field office →

Designation says a stretch of river matters to a listed species. It says nothing about the water quality in it — a designated reach can be, and often is, also on the Clean Water Act 303(d) list of impaired waters. The two are assessed by different agencies under different statutes.

Open the impaired waters map →

Every river and stream the federal government has designated as ESA critical habitat, the listed species each unit is designated for, and who manages the protected land around it.

Open the critical habitat map →

Watershed Explorer

Click any point in the country and read what six federal datasets say about it — flow, drought, fire, flood forecast, satellite cyanobacteria screening and Clean Water Act impairment — each one labelled with what it is actually a fact about.

Wildfire & Smoke Map — Delaware

Official NIFC fire perimeters and incident points under NOAA’s HRRR-Smoke near-surface forecast, filterable by size, state, and containment.

Open the national wildfire and smoke map →

Streamflow Map — Delaware

Every reporting USGS stream gauge in the country, coloured by how today’s flow ranks against that gauge’s own record for this calendar day.

Open the national streamflow map →

U.S. Drought Map — Delaware

The U.S. Drought Monitor — the country’s official weekly drought assessment — drawn across five severity categories from D0 to D4.

Open the national U.S. drought map →

Flood Outlook Map — Delaware

NOAA’s river forecast centres call the next few days at every forecast gauge in the country, on the National Weather Service’s own flood categories — action, minor, moderate and major.

Open the national flood outlook map →

Impaired Waters Map — Delaware

Every subwatershed in the country against the states’ own Clean Water Act assessments — what is impaired, what is still on the 303(d) list, what is causing it, and how much of the country nobody has assessed at all.

Open the national impaired waters map →

Cyanobacteria Bloom Map — Delaware

NASA and EPA’s satellites read a pigment index over roughly 2,300 U.S. lakes large enough to resolve at 300 m. A pre-screening indicator, not a health assessment, and never a substitute for your state’s advisory.

Open the national cyanobacteria bloom map →