This document provides instructions for using the WaterBudget component in the OMS 3 console to model the water budget and simulate discharge, actual evapotranspiration, runoff, and drainage for a given area. The component solves water budget equations using inputs of rainfall, potential evapotranspiration, and other parameters. It produces time series outputs of water storage, discharge, evapotranspiration, runoff, and drainage that can be used for hydrologic modeling and forecasting. Links are provided to download necessary files and access the component's source code.

1. Bancheri
LINKERS
JGrass-NewAge: WaterBudget component
Marialaura Bancheri
Correspondence:
marialaura.bancheri@unitn.it
Dipartimento di Ingegneria Civile
Ambientale e Meccanica, Trento,
Mesiano di Povo, Trento, IT
Full list of author information is
available at the end of the article
Abstract
These pages teach how to run the WaterBudget component inside the OMS 3
console. Some preliminary knowledge and installation of OMS is mandatory (see @Also
useful). This component deals with the water budget solution, for a defined layer. Given
the time series of the rainfall and of the potential evapotranspiration, the components
is able to estimate the water storage, to simulate the runoff and the actual
evapotranpiration for the considered layer, at different time-step. It also simulate the
possible drainage toward deeper layer. The package is perfectly integrated in the
JGrass-NewAge, and can be fed by other components, like the one providing the
potential evapotranspiration and connected to calibration algorithms. Once parameters
are assigned according to the selected model, it can be used for the forecasting water
storage in a selected point.
@Version:
0.1
@License:
GPL v. 3
@Inputs:
• Rainfall (mm);
• Potential evapotranspiration (mm);
• Discharge (if required) (m3
/s);
• Solver model (String);
• Q model (String);
• AET model (String);
• Area of the basin (A) (km2
);
• Non-linear reservoir parameter (a) (-);
• Non-linear reservoir exponent (b) (-);
• Maximum storage (mm);
• Pore volume in the root zone (nZ) (mm);
• Recharge rate (Re) (mm);
@Outputs:
• Water storage [mm];
• Total discharge [m3
/m2
];
• Actual evapotranspiration [mm];
• Quick runoff [m3
/m2
];
• Drainage from the layer [m3
/m2
].
@Doc Author: Marialaura Bancheri
@References:
• See References section below
Keywords: OMS; JGrass-NewAGE Component Description; Water budget

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Code Information
Executables
This link points to the jar file that, once downloaded can be used in the OMS console:
https://github.com/GEOframeOMSProjects/OMS_Project_WB/tree/master/lib
Developer Info
This link points to useful information for the developers, i.e. information about the code
internals, algorithms and the source code
https://github.com/geoframecomponents
Also useful
To run JGrass-NewAGE it is necessary to know how to use the OMS console. Information
at: ”How to install and run the OMS console”,
https://alm.engr.colostate.edu/cb/project/oms).
JGrasstools are required for preparing some input data (information at:
http://abouthydrology.blogspot.it/2012/11/udig-jgrasstools-resources-in-italian.
html
To visualize results you need a GIS. Use your preferred GIS, following its installation
instructions. To make statistics on the results, you can probably get benefits from R:
http://www.r-project.org/ and follow its installation instruction.
To whom address questions
marialaura.bancheri@unitn.it
Authors of documentation
Marialaura Bancheri (marialaura.bancheri@unitn.it)
This documentation is released under Creative Commons 4.0 Attribution International

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Component Description
This component solves the water budget, simulates the discharge and the actual evapo-
transpiration, according to the model chosen. The equation solved is:
dS(t)
dt
= J(t) − Q(t) − AET(t) (1)
where S [mm] is the water storage, J [mm] is the precipitation, Q the discharge [m3
/m2
]
and AET [mm] is the actual evapotranspiration. Both the discharge and the actual evepo-
transpiration can be given values or estimated from the S, according to different models,
i.e.:
Q(t) = aS(t)b
(2)
AET =
S(t)
Smax
ET(t) (3)
where ET is the potential evapotranspiration. Also the soil moisture can be modeled,
considering the porosity (n) and the depth of the root zone (Z). In this case, the equation
solved is:
nZ
ds(t)
dt
= J(t) − Q(t) − AET(t) (4)
The component, given the maximum recharge rate of the lower layer (Re), is also able
to estimate the drainage toward the deeper layers, eq. 5 and the direct runoff from the
considered layer, eq. 6
R(t) = min(Q(t), Re) (5)
Qquick(t) = Q(t) − R(t) (6)
Detailed Inputs description
The input file is a .csv file containing a header and one or more time series of input data,
depending on the number of stations involved. Each column of the file is associated to a
different station.
The file must have the following header:
• The first 3 rows with general information such as the date of the creation of the file
and the author;
• the fourth and fifth rows contain the IDs of the stations (e.g. station number 8:
value 8, ID, ,8);
• the sixth row contains the information about the type of the input data (in this
case, one column with the date and one column with double values);
• the seventh row specifies the date format (YYYY-MM-dd HH:mm).
All the previous information shown in the figure 1.

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Figure 1 Heading of the .csv input file
Rainfall
The rainfall is given in time series of (mm) for the investigated station .
Evapotranpiration
The evapotranpiration is given in time series of (mm) for the investigated station.
Discharge
The discharge is given in time series for the investigated station in (m3
/s). The discharge
values are directly converted in to (mm), given the value of the area of the basin. This
values are needed in the case the user wants to solve the water balance only using external
values, otherwise the component simulates the discharge, using the previous models, eq.
2.
Solver model
The Solver model field is a string in which the user specifies the integrator to use of the
solution of the ODE 1. There are two options :”dp853” which is the Dormand-Prince
8(5,3) integrator and ”Eulero”, which is the Euler integrator.
Q model
The Q model field is a string in which the user specifies the model for the discharge:
”NonLinearResevoir” or ”ExternalValues”.
AET model
The AET model field is a string in which the user specifies the model for the evapotran-
spiration: ”AET” or ”ExternalValues”.
Area of the basin
A is the area of the basin expressed in (km2
).
Non-linear reservoir parameter (a)
Non-linear reservoir parameter is the a parameter in eq. 2
Non-linear reservoir exponent (b)
Non-linear reservoir exponent is the b exponent in eq. 2
Maximum storage
Maximum storage is the variable Smax in eq. 3. It is expressed in (mm)

5. Bancheri Page 5 of 11
Pore volume in the root zone
The pore volume in the root zone is the variable nZ in eq. 4 and it is the product of the
soil porosity n and the depth of the root zone Z.
Recharge rate(mm)
The Recharge rate is the variable Re in eq. 5 and it is the maximum recharge rate towards
the lower layer.
Detailed Outputs description
Water storage
The water storage output is given as a time series at a given point. Its units are [mm].
Figure 2 shows the results of the simulation obtained using the data from a station in the
Posina river basin.
0 10000 20000 30000 40000
0.0000.0050.0100.0150.0200.0250.030
Water storage
Time[h]
S[mm]
Figure 2 Time series of water storage for a station in the Posina river basin.
Discharge
The discharge output is given as a time series at a given point. Its units are [mm3
/m2
].
Figure 3 shows the results of the discharge simulation obtained using the non linear
reservoir model.

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0 10000 20000 30000 40000
0.00.51.01.5
Discharge
Time[h]
Q[mm]
Figure 3 Time series of discharge for a station in the Posina river basin.
Actual evapotranspiration
The actual evaotranspiration output is given as a time series at a given point. Its units
are [mm]. Figure 4 shows the results of the AET simulation obtained considering it a
function of the water storage.

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0 10000 20000 30000 40000
0.00.20.40.60.81.0
Actual ET
Time[h]
AET[mm]
Figure 4 Time series of AET for a station in the Posina river basin.
Runoff
The runoff output is given as a time series at a given point. Its units are [mm]. Figure 5
shows the results of the runoff simulation, considering the maximum recharge rate of the
lower layer equal to 0.2 [mm].

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0 10000 20000 30000 40000
0.00.20.40.60.81.01.2
Runoff from the layer
Time[h]
Qquick[mm]
Figure 5 Time series of runoff for a station in the Posina river basin.
Drainage
The drainage output is given as a time series at a given point. Its units are [mm]. Figure
6 shows the results of the runoff simulation, considering the maximum recharge rate of
the lower layer equal to 0.2 [mm].

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0 10000 20000 30000 40000
0.000.050.100.150.20
Drainage toward the lower layers
Time[h]
R[mm]
Figure 6 Time series of drainage toward a deeper layer for a station in the Posina river basin.
Examples
The following .sim file is customized for the use of the WaterBudget component. The .sim
file can be downloaded from here:
https://github.com/GEOframeOMSProjects/OMS_Project_WB/tree/master/simulation
import static oms3.SimBuilder.instance as OMS3
def home = oms_prj
def startDate= "1994 -01 -01 00:00"
def endDate= "1998 -12 -31 00:00"
OMS3.sim {
resource "$oms_prj/lib/waterbudget -0.0.1 - SNAPSHOT -jar -with -
dependencies .jar"
model(while:" reader_data_J .doProcess") {
components {
" reader_data_J " "org. jgrasstools .gears.io. timedependent .
OmsTimeSeriesIteratorReader "
" reader_data_ET " "org.jgrasstools .gears.io. timedependent .
OmsTimeSeriesIteratorReader "
"ws" "waterBudget. WaterBudget "
"writer_S" "org.jgrasstools.gears.io. timedependent .
OmsTimeSeriesIteratorWriter "
"writer_Q" "org.jgrasstools.gears.io. timedependent .
OmsTimeSeriesIteratorWriter "
"writer_ET" "org. jgrasstools.gears.io. timedependent .
OmsTimeSeriesIteratorWriter "
" writer_Quick " "org.jgrasstools.gears.io. timedependent .
OmsTimeSeriesIteratorWriter "
"writer_R" "org.jgrasstools.gears.io. timedependent .
OmsTimeSeriesIteratorWriter "
}

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parameter{
" reader_data_J .file" "${home }/ data/rainfall.csv"
" reader_data_J .idfield" "ID"
" reader_data_J .tStart" "${startDate}"
" reader_data_J .tEnd" "${endDate}"
" reader_data_J .tTimestep" 60
" reader_data_J . fileNovalue " " -9999"
" reader_data_ET .file" "${home }/ data/ET.csv"
" reader_data_ET .idfield" "ID"
" reader_data_ET .tStart" "${startDate}"
" reader_data_ET .tEnd" "${endDate}"
" reader_data_ET .tTimestep" 60
" reader_data_ET . fileNovalue " " -9999"
// parameter of the component (see " Detailed Inputs description "
section for more info)
"ws. solver_model " "dp853"
"ws.Q_model" " NonLinearReservoir "
"ws.ET_model" "AET"
"ws.A" 115.4708483
"ws.a" 752.3543670
"ws.b" 1.75744
"ws.s_max" 0.005704
"ws.nZ" 1
"ws.Re" 0.2
"writer_S.file" "${home }/ output/Storage.csv"
"writer_S.tStart" "${startDate}"
"writer_S.tTimestep" 60
"writer_S.fileNovalue " " -9999"
"writer_Q.file" "${home }/ output/Q.csv"
"writer_Q.tStart" "${startDate}"
"writer_Q.tTimestep" 60
"writer_Q.fileNovalue " " -9999"
"writer_ET.file" "${home }/ output/ET.csv"
"writer_ET.tStart" "${startDate}"
"writer_ET.tTimestep" 60
"writer_ET. fileNovalue " " -9999"
" writer_Quick .file" "${home }/ output/Quick.csv"
" writer_Quick .tStart" "${startDate}"
" writer_Quick .tTimestep" 60
" writer_Quick .fileNovalue" " -9999"
"writer_R.file" "${home }/ output/R_drain.csv"
"writer_R.tStart" "${startDate}"
"writer_R.tTimestep" 60
"writer_R.fileNovalue " " -9999"
}
connect {
" reader_data_J .outData" "ws. inPrecipvalues "
" reader_data_ET .outData" "ws.inETvalues"
" ws. outHMStorage " "writer_S.inData"
"ws. outHMDischarge " "writer_Q.inData"
"ws. outHMEvapotranspiration " "writer_ET.inData"
"ws.outHMQuick" " writer_Quick .inData"
"ws.outHMR" "writer_R.inData"
}
}
}

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Data and Project
The following link is for the download of the input data necessaries to execute the WB
component (as shown in the .sim file in the previous section ) :
https://github.com/GEOframeOMSProjects/OMS_Project_WB/tree/master/data
The following link is for the download of the OMS project for WB component:
https://github.com/GEOframeOMSProjects/OMS_Project_WB
%
References