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Program StatePP is a complex program with extensive data requirements. The hydraulic <br />conductivity information is obtained from GMS for the current simulation, since this is used <br />internally in drain calculations. In addition to files from program AGG and program StateDGI, <br />additional control file information is necessary. This additional information includes definition <br />of stress periods, maximum recharge rate to help identify anomalous calculations, recharge <br />factors for aggregated structures that did not have GIS information, and decoding information for <br />county and vegetation abbreviations. Information on the current finite difference grid, including <br />number of layers, rows and columns, grid spacing and active cell codes by layer must also be <br />provided. Evapotranspiration parameters by vegetation type are also required, along with any <br />drains that are explicitly simulated. Program StatePP produces the actual MODFLOW files for <br />simulation of the recharge, evapotranspiration, wells and drains. In addition, five report or log <br />files that contain diagnostic information, two files containing information for post-processing <br />evapotranspiration output from MODFLOW, and 13 files that echo input data are produced by <br />this package. <br />Recharge package information is based on geographic locations of features. The sources of <br />infiltrating water that are considered in program StatePP include canal leakage, unconsumed <br />surface and groundwater from irrigation, boundary inflows that infiltrate, and precipitation on <br />both irrigated and non-irrigated lands. Canal leakage is based on total estimated canal seepage as <br />determined in program StateCU, which is then allocated according to the length of the canal in <br />each model cell. Weighting factors may be included to allow redistribution of this leakage <br />during the calibration process. Multiple structures may contribute to an individual model cell. <br />The calculated leakage is accumulated for each cell. Unconsumed surface and groundwater is <br />calculated in program StateCU for each structure; this is the maximum amount of water available <br />for recharge. This water, or a portion of it, is then applied to parcels associated with the <br />structure, then treated as recharge to cells, depending on how much of the individual model cell <br />is covered by these irrigated parcels. A weighting factor may be applied on a cell-by-cell basis. <br />Rim inflow zones are defined where surface water inflow to the model infiltrates within a <br />specified zone. As with other parameters, weighting factors maybe applied on a cell-by-cell <br />basis during calibration. Recharge from precipitation is handled in a similar manner, using <br />hydrologic unit codes and irrigation status to determine the recharge rate. All sources of <br />recharge are accumulated to prepare the recharge package file with the appropriate time steps. A <br />report file flagging those cells that have recharge exceeding the threshold value set in the input <br />file is generated to assist in checking and facilitating possible modification of parameters. <br />The well package files include explicit flows from municipal and industrial wells, and allocated <br />flows determined from program StateCU for agricultural wells. Agricultural wells may be <br />differentiated between sprinkler and flood irrigation uses. Total groundwater pumping is <br />estimated by structure, taking into account parcels that use groundwater that are associated with <br />a structure. Individual wells are associated with parcels that use groundwater to determine <br />pumping rates. Groundwater pumping is allocated to the wells proportionately based on well <br />capacity, which is also used to set the maximum pumping rate. The location of the well from the <br />GIS coverage is used to assign it to a cell, and the relative allocation to layers is determined from <br />