Salinity and Tides in York River

Estuary background image with color overlay


In this activity, students learn about tides and salinity in estuaries. They observe time-lapse models of tides and salinity distribution in the York River, part of the Chesapeake Bay Virginia National Estuarine Research Reserve. They learn how salinity changes with an incoming and outgoing tide, observing the dynamics of the salt wedge at various sites along the river. Students also make predictions about the salinity changes at each site based on their observations of the animation. They then use salinity data from monitoring stations along the river to see changes during a typical day, as well as describing the patterns of each salinity graph and comparing the graphs.

This activity consists of three parts that help deepen understanding of estuarine systems:

  1. Tides in the Chesapeake Bay
  2. Interaction of Tides and River Flow
  3. Salinity as Measured by Water Quality Stations in York River

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Students should understand that:

  • Analyze different forms of data and synthesize information to develop a hypothesis.
  • Explain how tides and the geology of the estuary affect water circulation in an estuary.
  • Describe daily patterns of salinity changes in the estuary.

Salinity and Tides in York River: Supporting Resources

Water Quality Specifics: Using a Hydrometer


Salinity and Tides in York River