Blaney Net Depth of Application

This polygon feature class defines locations and extents for net application depths calculated using the 'Modified Blaney-Criddle' equation. These areas are referenced in Figures SCR-1 through SCR-15 in the Water Use Permitting Manual, Vol. III, Part B, Section V. Supplemental Crop Requirement and Withdrawal Calculation. The South Florida Water Management District uses a modified Blaney-Criddle equation to determine evapotranspiration. The 'Modified Blaney-Criddle' is a variation of Blaney Criddle, which multiplies the ET from Blaney-Criddle by a coefficient that relates mean air temperature to the growth stage of a crop. Additionally, effective rainfall is calculated using the mean temperature and hours of daylight, the Blaney-Criddle ET, average monthly rainfall and soil factor. Further calculations consider average rainfall to drought rainfall (1-in-10 year drought). The difference between monthly drought effective rainfall and monthly ET becomes the basis for water allocations.