Healthy floodplains and wetlands provide critical ecosystem services to local and downstream communities by retaining sediments, nutrients, and floodwaters. Land conversion and degradation diminish floodplain functionality and services.
This preliminary web mapping application displays floodplain extent, stream channel metrics, and field site data. Data and the FACET software tool are available via the Data Download button. Please stay tuned for future updates.
Click the Select Area of Interest tab below to toggle between the Delaware River watershed or the Chesapeake Bay watershed. Click the Select Layers tab to toggle layers on the map. Click the User Guide button above for additional instructions.
Data and the FACET software tool are available via the Data Download button.
The floodplain layer is a geometrically simplified polygon that represents the "active" (field-defined; circa 2-year recurrence) floodplain extent.
The stream network shows the location of the stream based on topography. Each stream segment contains channel metrics computed by FACET.
Bank Height | The height of the streambank relative to the bank points and bottom of the channel. | Channel Width | The width between bank points. |
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Ratio of Channel Width to Depth | Channel width divided by bank height. |
Floodplain Width | The width of the floodplain extent at that cross section. |
Streambed Particle Size D50 | Median particle size of surface sediment in the stream channel, measured with about 100 pebble counts throughout the reach if wadeable, or ten grabs of bed sediment if non-wadeable. |
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Streambed Percent Fine+Sand | Fine sediment plus sand cover on the surface of the streambed that was measured during pebble counts throughout the reach, as a percent of total. |
Mean Floodplain Vertical Accretion Rate | The mean rate of vertical accretion on the active floodplain in each study site, measured using dendrogeomorphic techniques. Positive values are depositional with vertical growth, negative values are erosional with vertical loss. |
Mean Streambank Lateral Erosion Rate | Adjusted mean rate of lateral erosion of the eroding alluvial streambanks in each study site, using dendrogeomorphic techniques, adjusted by the proportion of streambank in the reach that was eroding to represent the whole reach. By definition of the method, all values are negative indicating erosion with lateral loss of streambank. |
Streambank Flux Rates | Sediment, sediment-nitrogen (N), or sediment-phosphorus (P) flux rate of alluvial streambank in the study site reach measured using dendrogeomorphic techniques. Positive rates indicate deposition of material, and negative rates indicate erosion of material. By definition of the method, all values are negative. Flux is calculated as the product of adjusted mean lateral erosion rate, mean streambank sediment bulk density, and mean streambank height times two. |
Floodplain Flux Rates | Sediment, sediment-nitrogen (N), or sediment-phosphorus (P) flux rate of active floodplain in the study site reach measured using dendrogeomorphic techniques. Positive rates indicate deposition of material, and negative rates indicate erosion of material. Flux is calculated as the product of mean vertical accretion rate, mean floodplain sediment bulk density, and mean total floodplain width. |
Net Balance Flux Rates | Net balance of the sediment, sediment-nitrogen (N), or sediment-phosphorus (P) flux rates of active floodplain and alluvial streambank in the study site reach. Positive rates indicate deposition of material, and negative rates indicate erosion of material. Flux is calculated as the sum of floodplain and streambank fluxes. |