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SIMULATION OF SURFACE RUNOFF FOR UPPER TAPI SUBCATCHMENT AREA (BURHANPUR WATERSHED) USING
SWAT
Vikash Shivharea, C.K. Singha, M.K. Goelb
a
b
Dept. of Natural Resource, TERI University, Vasant Kunj, New Delhi, India [email protected]
Division of Water Resource, National Institute of Hydrology, Roorkee, India –
[email protected]
INTRODUCTION

Water is a transparent fluid which forms the streams, lake, ocean, rain, and is one of the major
constituents of the fluids of living beings.
 Watershed is a hydrologic unit or an area of land from which water drains, running downhill, to a
shared destination or which produce water as the end product by interaction of precipitation and
the land surface.
Surface runoff is a term used to describe when soil is infiltrated to full capacity and excess water,
from rain, snowmelt, or other sources flow over the land.
 The amount of water that falls as a rain within a catchment area will either flow as a surface runoff
in the river which drains the basin or sinks into the ground to become ground water.

 GIS is an effective tool in watershed modeling as remote sensing derived information can be
well integrated with the conventional database for estimating runoff which can help in
planning suitable soil and water conservation measures. The SWAT works in conjuction with
ArcGIS.
 The current study was undertaken on the application of the SWAT model which integrates
the GIS information with attribute database to estimate the runoff
SWAT MODEL

SWAT is the acronym soil and water assessment tool.

SWAT is physically, continuous time scale, river basin or watershed scale model
developed by Dr. Jeff Arnold and jointly developed by the United States
Department of Agriculture-Agriculture Research Services (USDA-ARS) and
Agriculture Experiment Station in Temple, Texas.
 The model was developed to predict the impact of land management practices on
water, sediment and agricultural chemical yields in large complex watershed with
varying soil, land use and management condition over a long period of time.

Simulation of Hydrology of a watershed is divided into two groups:
- Land phase of the hydrological cycle
- The water, or routing phase of the hydrological cycle
Cont…
water balance is the driving force behind everything that happens in the watershed to accurately predict
the hydrological cycle sediment or nutrient movement.
 The computational components of SWAT can be grouped into different division hydrology, weather,
sedimentation, soil temperature, crop growth, nutrients, pesticides and agricultural management.


The hydrological cycle as simulated by SWAT is based on water balance equation:
SWt  SW0   Rday  Qsurf  Ea  Wseep  Qgw 
t
where,
SWt
SWo
T
Rday
Qsurf
Ea
Wseep
Qgw
i 1
: The final soil water content,
: The initial soil water content,
: Time in days,
: The amount of precipitation on day i,
: The amount of surface runoff on day i,
: The amount of evapo-transpiration on day i,
: The amount of percolation and bypass exiting the soil profile bottom on day i ,
: The amount of return flow on day I
SWAT model uses hourly and daily time step data to calculate surface runoff. The Green & Ampt. Method
is used for hourly data and an SCS curve number is used for daily computation.
 In SWAT model, a basin is delineated into various sub basin which are further subdivided into HRUs
which stands for hydrologic response unit. HRUs divide the sub basin into the area of similar land use, soil
type and slope.

Objectives
 This model is applied to conduct the study for estimation of runoff
in the Burhanpur Watershed. The aims and objectives of the
present study for the Burhanpur Watershed are:
 Delineate the watershed, flow direction, flow accumulation, and
stream network for the upper Tapi sub catchment area.
 Integrate the land use, soil map, slope, climatic data and create the
HRUs for each sub basin of the study area.
 Carry out the hydrological modeling and estimate the surface
runoff for the Burhanpur Watershed at the basin outlet.
Study Area
 The study area is sub-catchment of upper Tapi river
basin, namely Burhanpur watershed.
 It starts from Multai town in Betul district up to
Burhanpur district.
 It is situated in the southern border of Madhya
Pradesh near the bank of Tapi river.

Extent
21˚ 22’ to 21˚ 44’ North latitude
76˚ 6’ to 78˚ 14’ East longitude
 Total geographic area- 9364 sq.km.

Annual avg. rainfall- 830mm.
 The length of Tapi River which flows in
Burhanpur watershed from its source to
point-282 km.
outlet
Figure . SRTM DEM of Tapi Basin Up to Ukai dam
Figure. Location of study area with respect to Tapi basin
METHODOLOGY
The flow chart of methodology for the rainfall runoff modeling at the
basin outlet using SWAT
Model set up
The model was set up for the estimation of runoff. The main
procedure and various step followed in model application are
explained below:
 SWAT Project set up
 Automatic watershed delineation
 HRU Analysis
 Write input tables
 Edit SWAT inputs
 SWAT simulation
Model setup
HRUs Analysis
Automatic Watershed
delineation
HRUs Analysis
Figure. Soil Map of Tapi basin
Figure. Slope map of Burhanpur Watershed
 Write input tables:
The model requires daily data of precipitation and min. max.temprature.11
rain gauge station used in the catchment area Namely Multai, Betul, Atner, Chicholi,
Bhaindeshi, Chikhalda, Dharni, Akola, khandwa, Burhanpur, Jalgaon. The climatic data for the
study periods were prepared in .dbf format and than imported in the model.
 Edit SWAT Inputs:
This menu allows the user to edit the database file in the model. It
is used to setup a few additional inputs for running the SWAT model. The charecterstics
of soil data and the properties of the landuse were defined in the model as per indian
condition. The files were successfully rewritten and stored in personal Geodatabase of
the model. After this step, the model was ready to be run.
 SWAT Simulation:
SWAT Simulation has been done for the duration from January 01,
1992 to December 31, 1997. The SWAT model was run for the current study and output
was generated at monthly time step.
Results
Burhanpur (1992-93)
Burhanpur (1993-94)
Results
Burhanpur (1994-95)
Burhanpur (1995-96)
Conclusion
The simulated flow at the basin outlet have been compared with the
observed flows for four years of record (1992-93 to 1995-96)
and the results are encouraging. The coefficient of determination
for the monthly runoff was obtained as 0.82, 0.68, 0.92, 0.69 can
be considered as a satisfactory value.
SWAT model is an exhaustive model with extensive data
requirement. Some of the data were available for the study basin
while some other data requirements have been met from various
sources. There are some limitation of the present study…
 The land use map obtained from the GLCF. Now-a-days, NRSC
provides land use maps at finer resolution.
 the soil map is available four basic types. Since NBSSLUP
provides more detailed soil maps for the country.