Nacatoch Aquifer Model Groundwater Availability Model Boundary Condition Packages. 
Texas Water Development Board Groundwater Modeling Department

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WEL - WELL PKG
nctc_v101_wel.csv
nctc_v101_bc_pkg.gpkg\nctc_v101_wel
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cellid 	| integer 	| Format:  layer + rrrr + cccc (0-3 leading zeros for row and cols). Example: 200230245 (layer = 2, row = 23, col = 245)
lay 	| integer 	| Layer number
row 	| integer 	| Row number 
col 	| integer 	| Column number
ibound 	| integer 	| ibound number
q1	 	| float 	| pumping for stress period 1
qN 		| float 	| pumping for stress period N
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GHB - GENERAL HEAD BOUNDARY PKG
nctc_v101_ghb.csv
nctc_v101_bc_pkg.gpkg\nctc_v101_ghb
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cellid 	| integer 	| Format:  layer + rrrr + cccc (0-3 leading zeros for row and cols). Example: 200230245 (layer = 2, row = 23, col = 245)
lay 	| integer 	| Layer number
row 	| integer 	| Row number 
col 	| integer 	| Column number
ibound 	| integer 	| ibound number
top		| float		| the top elevation of cell
botm	| float		| the bottom elevation of cell
cond1 	| float 	| hydraulic conductance of the interface between the aquifer cell and the boundary for SP 1
condN 	| float 	| hydraulic conductance of the interface between the aquifer cell and the boundary for SP N
head1	| float		| ghb cell head in feet for SP 1
headN	| float		| ghb cell head in feet for SP N
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RCH - RECHARGE PKG
nctc_v101_rch.csv
nctc_v101_bc_pkg.gpkg\nctc_v101_rch
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cellid 	| integer 	| Format:  layer + rrrr + cccc (0-3 leading zeros for row and cols). Example: 200230245 (layer = 2, row = 23, col = 245)
lay 	| integer 	| Layer number
row 	| integer 	| Row number 
col 	| integer 	| Column number
ibound 	| integer 	| ibound number
rech1	| float 	| recharge for stress period 1
rechN	| float 	| recharge for stress period N
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EVT - EVAPOTRANSPIRATION PKG
nctc_v101_evt.csv
nctc_v101_bc_pkg.gpkg\nctc_v101_evt
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cellid 	| integer 	| Format:  layer + rrrr + cccc (0-3 leading zeros for row and cols). Example: 200230245 (layer = 2, row = 23, col = 245)
lay 	| integer 	| Layer number
row 	| integer 	| Row number 
col 	| integer 	| Column number
ibound 	| integer 	| ibound number
surf1	| float 	| elevation of ET surface for all Stress Periods
evtr1	| float 	| max ET flux rate for SP 1
evtrN	| float 	| max ET flux rate for SP N
exdp1	| float 	| ET extinction depth for SP 1
exdpN	| float 	| ET extinction depth for SP N

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STR - STREAM PKG
nctc_v101_str.csv
nctc_v101_bc_pkg.gpkg\nctc_v101_str
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cellid 	| integer 	| Format:  layer + rrrr + cccc (0-3 leading zeros for row and cols). Example: 200230245 (layer = 2, row = 23, col = 245)
ievt 	| integer 	| layer number recharge is applied to
row 	| integer 	| Row number 
col 	| integer 	| Column number
ibound 	| integer 	| ibound number
segment	| integer 	| elevation of ET surface for all stress periods
reach	| integer 	| max ET flux rate for SP 1
stage	| float 	| is the stream stage. The value of Stage is not used if ICALC>0. Stage is measured relative to the same datum as the rest of the model.  It is not measured relative to the stream bottom.
cond	| float 	| is the streambed hydraulic conductance.
sbot	| float 	| is the elevation of the bottom of the streambed.
stop	| float 	| is the elevation of the top of the streambed. The value of Stop is used if the option to calculate stream stage is active (ICALC>0) or when the streambed has zero flow.
width	| float 	| is the width of the stream channel. It is read only when stream stage is calculated (ICALC>0).
slope	| float 	| is the slope of the stream channel. It is read only when stream stage is calculated (ICALC>0)
rough	| float 	| is Manning’s roughness coefficient. It is read only when stream stage is calculated (ICALC>0).
flow1	| float 	| is the streamflow entering a segment for Stress Period 1. This value is used only for the first reach of each segment. The value should be specified as either 0 or blank when the reach number (Reach) is not 1. When the inflow to the first reach of a segment is the sum of the outflow from upstream tributary segments, Flow should be specified as -1. When the segment is a diversion, the Flow for the first reach is the amount to divert; however, there will be no diversion if the segment from which the diversion is obtained contains less than the value of Flow.
flowN	| float 	| is the streamflow entering a segment for Stress Period N. This value is used only for the first reach of each segment. The value should be specified as either 0 or blank when the reach number (Reach) is not 1. When the inflow to the first reach of a segment is the sum of the outflow from upstream tributary segments, Flow should be specified as -1. When the segment is a diversion, the Flow for the first reach is the amount to divert; however, there will be no diversion if the segment from which the diversion is obtained contains less than the value of Flow.
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For more information on the variables refer to:
USGS Open-File Report 00-92
MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model - User Guide to Modularization Concepts and the Groundwater Flow Process