Chesapeake Bay Facts

  • The Chesapeake Bay watershed is 7x larger than the state of New Hampshire
  • It takes 6 days for water to flow from the headwaters of the Susquehanna in Cooperstown, NY to the mouth of the river in Havre de Grace, MD
    • Sus transports more than a million tons of sediment to the Bay each year
  • Largest land-to-water ratio (14:1) of any coastal body in the world
  • 200 miles long
  • 11,684 miles of shoreline
  • Average depth of 21 feet
  • Widest point is at the mouth of the Potomac ⇒ 30 miles wide
  • Narrowest point ⇒ 2.8 miles wide
  • Salinity is the primary variable that changes throughout the length of the Bay
    • Brackish fills most of the Bay, but there is a higher percentage of fresh at the northern part and more salt at the mouth
  • Circulation of water
    • Warmer, less dense freshwater water flows near the surface from north to south
    • Dense, cold, saltier water flows near the bottom from the ocean, up the Bay
    • Thermocline - a transition layer between warmer water at the surface and colder water deep below
    • Halocline - a change in salinity with depth
    • Pycnocline - a rapid increase in water density with depth
graphic showing thermocline, halocline, and pycnocline

Last updated: March 6, 2018

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Annapolis, MD 21403


(410) 260-2470

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