Descriptive display bins
Below 75% saturation75–100% saturationAbove 100–125% saturationAbove 125% saturation
These colors only separate reported values for viewing. They are not oxygen-stress, ecosystem-health, impairment, treatment, safety, or regulatory thresholds.
How to read this
Fact: each marker is a recent USGS stream-site measurement of dissolved oxygen as a percentage of saturation. The popup preserves its time-series ID, measurement time, reported unit, and approval status. Limit: percent saturation relates measured dissolved oxygen to equilibrium under local conditions and can vary with temperature, atmospheric pressure, salinity, mixing, photosynthesis, sensor condition, and site context. It is not interchangeable with concentration in mg/L. One point does not represent an entire water body. The map infers no cause, trend, oxygen stress, ecosystem health, treatment need, safety, impairment, or compliance.
Source contract
USGS modern Water Data OGC API, latest-continuous, parameter 00301. Requests are anonymous, keyless, limited to stream sites in the visible bounding box and preceding 48 hours, capped at 500 features, and protected by a 60-second client cooldown. Missing, nonnumeric, negative, nonpoint, or older records are excluded. No credential, proxy, saved measurement snapshot, or proprietary GIS service is used. Source/license notes · USGS API documentation
