Riparian Buffer Bypassing in the Chesapeake Bay Watershed

The Chesapeake Bay is a valuable resource to its bordering states, both economically and biologically. Unfortunately, the Bay experiences high sediment and nutrient pollution from agricultural runoff entering the streams and rivers which are located within its watershed. These excess nutrients lead to algal blooms and depleted oxygen, resulting in die-offs of larger fish species. The Environmental Protection Agency has promoted Best Management Practices such as forested Riparian Buffer strips in attempts to remove these pollutants from the river systems. Riparian buffer strips are areas of land planted with vegetation and forests along the edges of agricultural fields.

These strips are designed to retain sediment and nutrients on the land, and out of the nearby streams. However, even with implementation of buffer strips throughout the watershed, nutrient pollution has been at constant dangerous levels. It has been observed that field drainage patterns often channel runoff into a few concentrated points of exit. This has caused the majority of runoff to flow off of the field without being able to contact the buffer strip, restricting pollution reduction potential of the buffer.

This summer I will be using Geographic Information Systems mapping to determine the extent of buffer bypassing in the watershed, by creating runoff flow accumulation maps for approximately 50 agricultural fields. These maps will allow me to determine the amount of runoff which flows through each channel and also the buffer effectiveness when the actual area of contact is taken into account. In order to see the effects of this in action, we will be monitoring a buffer-bypassing channel on Burlington Plantation, located in James City County. My advisors will be Jim Kaste and Greg Hancock of the geology department and I will be working with Dylan Reilly and Emma Caverly on the project. They will be studying specific dissolved and suspended components of runoff while I will focus on the discharge through the channel. We hope to know the extent of bypassing in the watershed by the end of the summer as well as the significance of these channels to pollution addition to the Bay.