Eastern Snake Plain Aquifer Model

The Eastern Snake Plain Aquifer Model Committee and subcommittees meet as needed.

Meeting dates, places, or times are subject to change.

The ESPAM2 Recharge Tools are designed to produce input files for the utility MKMOD. MKMOD performs water-budget calculations and creates input files for the ESPAM2.0 aquifer flow model.

The files produced by ESPAM2 Recharge Tools are:

• *.cel contains the area each model grid cell and its status as active or inactive in the model.
• *.cnl contains the locations and seepage rates of leaky canals.
• *.div contains volumes of diversions from surface-water bodies.
• *.ent contains characteristics of regions of similar irrigation practice and water source, known as “irrigation entities.”
• *.eti contains the depth of evapotranspiration expected on any irrigated lands that might occur in each model cell.
• *.fpt contains locations and water flows associated with various water-budget components that may be associated with explicitly identified geographic locations called “fixed points.”
• *.iar contains the number of square feet of irrigated lands associated with each irrigation entity, in each model cell.
• *.nir contains the depth of recharge from precipitation that occurs on non-irrigated lands (if any) in each model cell.
• *.off This file contains the geographic locations and pumping volumes of wells that deliver water into streams or canals for use at distant locations, where the volume rediverted from the stream or canal is NOT already included in diversions reported in the *.div file.
• *.pch contains the locations of streams and rivers other than the Snake River, and gives the volume of seepage from these to the aquifer, or gains these receive from the aquifer.
• *.pre contains the depth of precipitation on each model cell.
• *.sol contains a parameter-estimation zone number for each model cell, for use by parameter-estimation software in adjusting the recharge from precipitation on non-irrigated lands.
• *.trb contains estimates of subsurface inflow from tributary valleys into the Eastern Snake Plain Aquifer, and the locations where those flows are represented to occur.

The MKMOD software relies upon three other input files which are built by hand and not produced by ESPAM2 Recharge Tools:

• *.mdl contains information regarding the time discretization of the model, a brief summary description, and parameters for automated parameter adjustment of *.nir and some points in *.fpt data sets.
• *.red contains information regarding reductions to the *.iar areas for non-irrigated inclusions such as roads, haystacks, buildings and farmyards that may be represented as irrigated in the *.iar data.
• *.eff contains efficiency, seepage and runoff parameters for the On-Farm algorithm of MKMOD software, used to calculate the net recharge or discharge associated with irrigated parcels.