The stratification index for a Shelf Break Front is an indication of how productive phytoplankton will be. When the stratification index is approximately 1.5, this produces a nutrient-rich environment for the growth of phytoplankton. Too much higher, and the stratification of the water column will not cause the upwellings of nutrients needed for the phytoplankton to prosper, too much lower, and the water will be too turbulent for the phytoplankton to use the nutrients available. Stability of the front, in addition to nutrients, is a key to phytoplankton production. An illustration of the stratification index for Narragansett Bay is shown here, with the average speeds estimated, using actual bathymetry for the bay, and an estimated C D for silt, which composes much of the bay's bottom. Using the Stokes Spreadsheet, and some customization on the size of silt particles, I used a C D = 0.0011. More accurate speed measurements and detailed C D values for the Bay's bottom could yield a higher fidelity image.