Flooding in the Chesapeake Bay Watershed: Teach About It!

October 10th, 2011 by Sarah

Chesapeake Research Consortium Staffers take a break from bird watching on a flooded pier to pose for a photo during an outing to Jug Bay Wetland Sanctuary.

Last week, Margaret Enloe, the Chesapeake Bay Program’s Communications Director, contributed an excellent guest blog about the impacts September’s flooding event had on the Bay.   Now that you understand some of the Bay dynamics that may have been influenced by the recent influx of water, sediment, nutrients, and contaminants, let’s examine how you can convey this information to your students.

Lesson Plans

Don’t worry; you are not up a flooded creek without a paddle. There is a wealth of lesson plans available to help you teach about flooding, many of which are aligned with national content standards!  Here are a few samples to help you get started:

  • Flood! – In this Discovery Education lesson plan, students in grades 6-8 will discover that different types of soil have different capacities for retaining rainwater. At the end of the lesson, they should also understand that if the soil in an area is already saturated with rainwater, flooding problems can ensue.
  • Floods: Rising Waters and You – 9-12 graders will investigate the relationships between human-made structures and flood waters in these PBS American Field Guide Lessons.
  • Flood! Classroom Activity – Students will construct a model of a river system and explore the use of manmade levees in this NOVA Teachers lesson plan.
  • Floods – Young students can learn about and play games related to floods on FEMA’s For Kids website.  Children can read “The River Rises; The Disaster Twins’ Flood Story,” take a flood math quiz, or play the “Water, Wind, and Earth Game.”
  • What is a Flood Plain? – Its not all science when if comes to flooding.  PBS has developed this lesson for 7-12 grade classrooms that wish to address content related to economics and/or geography.
  • Ancient Flood Stories – National Geographic has provided this lesson to help educators discuss the evidence that ancient floods may have helped to create the Black Sea. Students will practice their creative writing by composing stories about what it might have been like immediately before and during the flood.

On September 21, 2011 Chesapeake Research Consortium staffers hiked along the flooded Railroad Bed Trail in Jug Bay Wetland Sanctuary.

Ask a Scientist

Remember to end your flooding lesson by “bringing it local!” Discussing the impacts that September’s flooding had on the Chesapeake Bay, and on areas within the Chesapeake Bay Watershed, will provide your students with a real-world example that they have experienced.  Ask your students if their families took any steps to prepare for the flooding (see FEMA’s Flood website for helpful safety tips), or discuss what happened on school grounds.  This can help bring your flooding lesson to life, and ensure that it is relevant to your students.

Another great way to get your students interested in learning about floods and our local watershed is to have them interact with professionals who work in Science, Technology, Engineering, and Math (STEM) related fields.  The Chesapeake Bay Program Partnership has many experts across the watershed who can answer your class’s emailed questions about the response of the streams, rivers and the Bay to the extreme rainfalls and flood conditions.  You can have your class assemble a list of their questions, and email them to us using this online form.  The Chesapeake Bay Program has experts on the following flooding-related topics:

  • River flow, flood conditions, loads of pollutants, comparison of other major flood events
  • Impacts of flood event on MD’s Bay waters and living resources
  • River monitoring in MD
  • Impacts of flood event on VA’s Bay waters and living resources
  • River monitoring in VA
  • River monitoring in PA
  • Monitoring in PA and New York
  • Overall watershed-wide effects and how CBP partners are monitoring the impacts
  • Data and info from NOAA Bay monitoring buoys, research vessels, and satellite imagery
  • Impacts on the Bay/other contacts in the watershed for more information
Sarah Brzezinski a Chesapeake Conservancy Intern and serves as the manager of Bay Backpack. She is a former Chesapeake Research Consortium/Chesapeake Bay Program Fostering Stewardship Staffer.

Flooding in the Chesapeake Bay Watershed: Impacts on the Bay

October 3rd, 2011 by Margaret Enloe

During the flooding event on September 9, 2011, nutrients, sediment, garbage, and debris were washed downstream from the Susquehanna River into Chesapeake Bay at a near-record rate. Image courtesy of NASA Earth Observatory.

Near record flow of the Susquehanna River was measured by the USGS on the morning of Friday, September 9th. River flow at Conowingo Dam, where the river enters the Chesapeake Bay, was 775,000 cubic feet per second (CFS)!  2011 will most likely be one of the highest annual flow years on record for the Susquehanna River, primarily as a result of both the September tropical storms and a wet spring across the watershed.  In addition to the Susquehanna, high river flows were measured throughout other parts of the six-state Chesapeake Bay watershed. Your class can investigate real-time streamflow data at a site near your school by using the USGS WaterWatch website.

Likely Impacts on the Bay

Last month’s blog reported that the Chesapeake Bay received a short term water quality boost from Hurricane Irene due to the physical mixing of the Bay’s waters by extreme winds and waves that sent oxygen-rich surface waters into the deeper channels that are normally lacking oxygen at this time of year.  It is true that the physical mixing that resulted from Hurricane Irene did increase the amount of dissolved oxygen near the bottom of the Bay; however the shear magnitude of the more recent flood waters, combined with the loads of nutrients and sediments, will likely have a negative effect on the Bay’s health.  We will only understand the true impacts with the passage of time and through the combined monitoring and assessments by the Chesapeake Bay Program’s many partners.

Things to Watch:

  • Of potential concern to the next year’s crop of underwater bay grasses is the physical scouring of the Bay bottom (particularly in the Susquehanna Flats and the upper tidal Potomac River) resulting in the removal of vegetation living below the sediment surface—the ‘seeds’ for next spring’s plants.
  • The Bay’s oyster bars and other important hard bottom habitats will likely get a new layer of silt covering them in the coming days and weeks ahead, which will directly impact oyster and other bottom dwelling organisms.
  • Much of this sediment will stay around and, with the help of winds and tidal currents, find itself back up in the water column as early as this coming fall and well into the next year.
  • The flood of freshwater into a salty Bay can have impacts on the Bay’s critters like oysters which can’t just get up and move if the much lower salinity conditions last for an extended period of time.

Up on the Susquehanna River, the volume of flood waters will scour the bottom, causing sediment and nutrients previously ‘trapped’ behind the Conowingo Dam to be freed and sent down to the Bay.  These released sediments will likely bring not only more nutrients to the Bay, but also long-buried chemical contaminants.

USGS will be taking samples for analysis of bacteria, pesticides and trace metals over the course of the flood event to help understand the chemical contaminant loads entering the Bay from such a major flood event.  Several months from now we will be able to quantify these loads and the potential impact to a much higher degree.

Timing of the Floods Lessens the Opportunity for Further Impacts

When it comes to flood events and their impact on the health of local waterways and the Bay overall, it is timing that makes the big difference in terms of whether there is a short term (weeks to a month) or a long lasting (months to years) impact on the Bay ecosystem.  Based on historical data, we expect and will be monitoring the following:

  • Bay grasses: We are at the end of the underwater Bay grasses peak growing season, so impacts will be fewer than if the flooding occurred in June or July.
  • Living organisms in the Bay: As this is not a major spawning period for Bay living resources, the long term impact on their populations will be minimal.
  • Nutrients & sediment to the Bay: Given that this flood event is happening as the summer season comes to a close, there is less opportunity for long lasting water quality impacts in terms of nutrient and sediment pollution. By the spring, a majority of the nutrients should have worked their way through the Bay system.  Additionally, cooler temperatures, shorter days, reduced biological activity, and cloudy waters should prevent large algal blooms from growing in the excess nutrients.

Be sure to check in with Bay Backpack next week to learn how to teach about flooding in your classroom!

Margaret Enloe is the Communications Director for the Chesapeake Bay Program / Alliance for the Chesapeake Bay.