Using a computer-simulated hydrological model (SWAT), the researchers estimated groundwater recharge due to rainfall in a region of interest in Texas, US. They delineated the watershed using DEM data, defined hydrologic response units based on land use and soil maps, and input weather data to run the SWAT model over 15 years. The model was used to calculate infiltration over 10 years, from which groundwater recharge was estimated. The researchers acknowledged their guide and department for assistance with the project.

1. Using Computer-simulated
hydrological model(SWAT) to
estimate the ground-water recharge
due to rainfall
Presented by - Dhiraj Jhunjhunwala 13BCL0213
Shubham 13BCL0037
Prateek Aggarwal 13BCL0099
Ramit Raunak 13BCL0259

2. Acknowledgement
We would like to express our heartfelt gratitude towards our
guide Prof. Dilip Kumar Barik who provided insight and expertise
that greatly assisted this project. At last, we would like to thank
our Programme Chair, Prof. Santha Kumar & our esteemed
faculties of Civil Engineering Department, SMBS .
Dhiraj Jhunjhunwala Prateek Aggarwal
Shubham Ramit Raunak

3. Statement of Problem
Estimation of Ground-water recharge by the
water-balance approach due to rainfall in less
precipitous terrains

4. Region of Interest

5. SOFTWARES USED:
• ArcSWAT
• QGIS
• ArcGIS

6. SWAT Model
• SWAT (Soil & Water Assessment Tool) is a river basin scale
model developed to quantify the impact of land management
practices in large, complex watersheds.
• SWAT is a public domain model actively supported by
the USDA Agricultural Research Service at the Grassland, Soil
and Water Research Laboratory in Temple, Texas, USA.
• SWAT can be considered a watershed hydrological transport
model. This model is used worldwide and is continuously
under development.

7. Water-Balance Equation
• A general water balance equation is:
P = Q + E + S
Where,
P is Precipitation
Q is Runoff
E is Evapotranspiration
S is the change in storage (in soil or the bedrock)

8. SCS Hydrological Model
• The runoff curve number (also called a curve number or
simply CN) is an empirical parameter used in hydrology for
predicting direct runoff or infiltration from rainfall excess.The
curve number method was developed by the USDA Natural
Resources Conservation Service.
• The runoff curve number is based on the area's hydrologic soil
group, land use, treatment and hydrologic condition.
• The runoff equation is:

9. • Where,
Q is runoff ([L]; in), P is rainfall ([L]; in) S is the potential
maximum soil moisture retention after runoff begins ([L]; in),
Ia is the initial abstraction ([L]; in), or the amount of water
before runoff, such as infiltration, or rainfall interception by
vegetation; historically, it has generally been assumed that ,
Ia = 0.2S although more recent research has found that may
be a more appropriate and accurate relationship.

10. Methodology
• Following are the steps carried out to estimate the
ground-water recharge:
• Step 1: Determine the region of interest(Texas, US ), bound by the
specific set of coordinates.
• Step 2: Download the DEM(Digital Elevation Model) of the Region
of Interest, geo-referencing in QGIS
• Step 3: Delineate the watershed using the DEM in the ARCSWAT
interface
• Step 4: LULC map was used as an input to define the HRUs, and
was clipped by the watershed boundary. (National Landset
Dataset)
• Step 5: US STATSGO Soil map was input into the model, followed
by the input of slope map (formulated by ArcSWAT using the
DEM)

11. • Step 6: Weather data (precipitation & temperature) was
downloaded and input into the swat model.
• Step 7: Input files were written and swat was setup for run. The
model was run for 15 years (from 1995-2010), with 5 years of skip
and time-step monthly.
• Step 8: Infiltration was calculated with the SWAT output data for
10 years(2000-2009)and the graph was plotted

12. Watershed

13. Watershed Boundary :

14. Streams & Basins:

15. NLCD 2011 LULC Map
(downloadedfromwww.mrlc.gov/NLCD01_data.php)

16. LULC,SOILANDSLOPECLASSIFICATIONREPORT:

17. Soil Classification Map (USSTATSGO):

18. Genericlandcoverusedindatabase

19. SWAT Model Output :

24. Thank You!