A brief report on my work in North Eastern Space Applications Centre (2014-2015), Umiam-793103, Meghalaya, India

1. Amaljit Bharali
Research Scientist(Hydrology)
NER-DRR

2.  Primarily engaged in Hydrology and Watershed related
activities, Hydrological and Hydraulic modelling of river
systems
 NESAC Activities till now:

3. 3
 Flood Early Warning Systems (FLEWS) Project Works
 Post FLEWS Field survey of major flood prone rivers in Assam
 NER-DRR Centralized Infrastructure database preparation
 Development & Dissemination of web-based Spatial Decision
Support Systems (SDSSs) for FLOOD under NER-DRR programme
 SBIK Level 1 Flood Zonation database generation For North Eastern
States
Activities of 2014

4. 4
 Upgrading existing FLEWS parameters & procedure
◦ Correction of digital river database
◦ Preparation of LULC and Soil data for model preparation
◦ Catchment Delineation and model preparation using HEC-GeoHMS
◦ Correction to newly built HEC-HMS models
 Research & Development Activities
 Operational FLEWS activities
Activities of 2015

5.  River Systems digitized from high resolution imageries.
 DEM (SRTM 30M/SRTM 90M) filtered, hydrologically corrected,
digitized rivers burned and finally delineated.
 Manual correction of outlets, junctions and delineated sub-
basins.
 The main river routing model has been changed from
Muskingum to Muskingum-Cunge keeping in view its suitability
for Ungauged Catchments
 Consideration of Antecedent Moisture Content (AMC) to account
for rainfall variability during the flood season.
 Calibration of models with existing stage-discharge database

6. 1. LAND USE
 SBIK LULC 11-12 2nd cycle data
 LULC classes sliced down to 26 classes from 4 broad classes previously to
increase SCS Curve Number heterogeneity
Land
Forest
Water
Built-Up

7. 2. SOIL
• SBIK 250k Soil database
• The four main classes of soil A,B,C & D has been computed using
texture, drainage pattern and type of soil

8. 8

9. HEC-GeoHMS
Screen
HEC-HMS

11.  Urban/Flash Flood studies
◦ AOI - Shillong Urban,Guwahati
◦ Softwares – HEC-HMS, MIKE FLOOD, HEC-RAS, SWMM, FLO-2D
◦ Creation of the Guwahati Urban watershed model with inputs
from GMDA, ASDMA and IIT Guwahati
◦ Testing MIKE 21 two-dimensional module with complex
bathymetry
 Source Sinks pairs
 Building footprints
 Riverine Flooding study
◦ Lakhimpur - Ranganadi River, Goalpara – Krishnai, Dudhnoi
Rivers, Dhansiri River, Nagaland
 HEC-HMS accuracy test with available DEMs

12. Dhansiri_Nagaland
Shillong Wamukhra
Guwahati city -
Ganeshguri to Zoo

13. Guwahati Zoo Tiniali
Water Depth
0 - 0.01
0.01 - 0.2
0.2 - 0.45
0.45 - 0.68
0.68 - 0.93
0.93 - 1.75

14. FLOOD SIMULATION using MIKE 21 Hydraulic Model
Two-Dimensional Hydraulic Simulation
(Case study in Ranganadi river in Lakhimpur
District, Assam)
Simulation of
rainfall over
Guwahati using
Source & Sink pairs

16. Proposed locations of ARG stations for Guwahati on the
request of Assam State Disaster Management Authority
(ASDMA).

17. WRF Input
to the
HEC-HMS
Model
Heavy Rainfall
Forecast
FLOOD
ALERTComputed high discharge peak
ASDMA
Disaster
Control Room
District
Administratio
n
IMD
Alert
uploaded
in
ASDMA
website
(being
implementin
g agency)
Alert
Recipients

18. ABSOLUTE
SUCCESS
PARTIAL
SUCCESS
NO FLOOD
REPORTED
FLOOD
REPORTED
FLOOD
REPORTED
Validation
of issued
flood alerts
from
multisource
information
RISAT-1 HH Polarization
Post Alert Imagery
showing inundation

19.  Total no. of alerts
issued (till date) –
144
 Total no. of
absolute success –
89
 Total no. of partial
success – 43
 Total no. of failures
– 12 (including 2
alerts without
validation)
60%
32%
8%
Alerts Issued: 2014
Absolute
Success
Partial
Success
62%
30%
8%
Alerts Issued: 2015
Absolute
Success
Partial
Success
Failure

20.  Integration of combined MIKE NAM hydrologic model + MIKE 11
hydraulic model in FLEWS operational module to strengthen the
present hydrological analysis of FLEWS.
 Also Urban Flash flood Alert system can be started with MIKE
Urban Module/PCSWMM availability.
 Sediment transport and morphological modelling study
incorporation under NER-DRR.
 Automation of FLEWS for better decision support help. In the first
phase, automation of field data collection and alert
dissemination will be targeted.
 LIDAR DSM integration can be started after a pilot study which
we have taken up recently.
 Building flood forecasting models for all the flood prone states
of North-East.

21. MIKE FLOOD setup in Krishnai-Dudhnoi RiversInundation using MIKE FloodComparison with NRSC historic inundation dataVillages inundatedRC Level Inundation check

22. 3
2
1
Minor
River
Junction
Main Channel
Initial Flow Condition
y = 12.706x2 - 2158.4x + 91663
0
500
1000
1500
85 90 95
Rating Curve - Dikhow
Q
Poly. (Q)
Upstream
Boundary
Condition -
1 Upstream Boundary
Condition -2
Inundation
Check Site

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