Humboldt Bay

Humboldt Bay sits behind a long sandspit on California’s North Coast, enclosing roughly 25 square miles of estuary at high tide. It’s the state’s largest oyster-growing region by lease count and by harvest volume, with growers concentrated in the north end of the bay where strong tidal exchange and steady freshwater inflow combine to feed a productive shellfish system.

What we’re tracking

The Humboldt portion of the project pulls together public readings from:

• Offshore buoys: wave height, sea-surface temperature, and weather conditions out beyond the bay’s entrance.
• Sensors inside the bay: continuous readings of water temperature, salinity (saltiness), and dissolved oxygen at fixed stations.
• Tide gauges: long-running NOAA stations on the North Spit and nearby. They record how the water level rises and falls, which is the backbone of almost everything else.
• Harmful-algae monitoring: weekly samples from the state’s CalHABMAP program, tracking the algae species that can make shellfish unsafe to eat. (One South Bay site was recently retired but still appears on the map for context.)
• River-flow gauges: flow measurements on the Mad and Eel rivers (and tributaries where instrumented), which determine how much fresh water reaches the bay and how layered or mixed the water column gets.

The map below shows every public station feeding the project, plus an optional layer for the locations of the bay’s shellfish farms.

What comes next

Live readings and alerts are on the roadmap. For now, this page is about what’s being collected and why.