The Delaware River Estuary extends 133 miles from Morrisville, Pa./Trenton, N.J. south to Lewes, Del./Cape May, N.J., where the Delaware Bay meets the Atlantic Ocean.

Because the river is not dammed from the ocean, it experiences regular tidal changes anywhere from six to ten feet!

This 24-hr time-lapse video was taken in September 2020 at Philadelphia's Washington Avenue Green, which is one of DRBC's bacteria monitoring sites.
The camera took one photo/minute, and the playback is 30 frames/second.

Because the Delaware River Estuary is tidal, it is important to know when tides are predicted.

• Tides change daily and are intensified by the phases of the moon (full, new, quarter)
  
  
• Most areas in the Delaware River Estuary have two high tides and two low tides a day
  
  
• When checking the tides, it is important to note the day, times and heights of low and high tides
  
  

Tide predictions are available up to two years in advance from the National Oceanic and Atmospheric Administration's (NOAA) Tide Predictions website. This site provides a graphical display, as well as tabular listing, of the predicted tides, has options for downloading or printing, and a number of other features.

• NOAA Tide Predictions - Delaware
  
  
• NOAA Tide Predictions - New Jersey (scroll down to Delaware Bay, Eastern Shore)
  
  
• NOAA Tide Predictions - Pennsylvania
  
  
• NOAA Tides and Currents: Water Level Information (broken down by state)
  
  
• NOAA Tides and Currents: Current Predictions

Additional Links of Interest:

• NOAA's Tides and Currents Webpage
  
  
• NOAA's Delaware Bay Operational Forecast System
  
  
• NOAA's Physical Oceanographic Real-Time System for the Delaware River and Bay (PORTS)
  
  
• NOAA's Coastal Inundation Dashboard
  
  
• NOAA/NWS Philadelphia/Mount Holly Forecast Office's Marine Forecasts and Tidal Information
  
  
• Tide Times and Tide Charts