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Objectives
• To find a suitable site for dam construction.
• To study Q-GIS and ENVI softwares.
• To find a perfect area for catchment fulfilling requirements ofsoil, rainfall, slope, etc
• To generate land use/cover classification using LANDSAT 8satellite images.
• To prepare thematic maps of study area.
Definition• DAM- A dam is a barrier that impounds water or underground
streams. Reservoirs created by dams not only suppress floodsbut also provide water for such activities as irrigation, humanconsumption, industrial use, aquaculture, and navigability.Hydropower is often used in conjunction with dams togenerate electricity.
• CATCHMENT- The collection of rain water over a naturaldrainage area during rainfall.
• RESERVOIR- A reservoir usually means an enlarged natural orartificial lake, storage pond or impoundment created using a
dam or lock to store water.
Reason for dam/catchment construction• Flood control.
• Agricultural purposes.• Hydro-electricity.• Water reservation.
Recently lakhs were affected by severe droughts in Maharashtra.Due to failure of good monsoon and excessive heat drying up therivers resulted in crop failure and subsequently leading to farmer
suicides.Maharashtra may require more catchment areas which can supplywater in extreme weather or can give relief to affected areas
rather than depending on fresh rains.
Dam site requirement criteria
• Area having gentle slope rather than steep slope (slopestability).
• Area receiving adequate rainfall.• Area away from settlement and agricultural fields.
• Permeability of soil or type of soil.• Water table.
• Effects on forest and wildlife.• Earthquake faults.
• Stream flow/Watershed.
Study Area Location
• Location- Lavale, Pune, Maharashtra• Area is enclosed between these intervals:-(By GPS)
18°ϯϮ′ϯϯ.ϬϮ͟N ϳϯ°ϰϯ′Ϯϴ.ϳϬ͟E to 18°ϯϮ′Ϯϭ.ϭϵ͟N 73°ϰϯ′ϱϳ.ϵϮ͟E to18°ϯϭ′ϱϯ.ϴϵ͟N 73°ϰϰ′ϬϮ.ϱϭ͟E to 18°ϯϭ′ϱϮ.ϰϳ͟N 73°ϰϯ′ϯϯ.Ϯϭ͟E .
• Construction of catchment area around Symbiosis valley.
Study Area
• Over-view of Study Area-1. Seasonal Rainfall Pattern.
2. Study of Soil Map ,Land Use Map, HSG Map, Drainage DataMap and Runoff Coefficient Map.
• Topographically and geographic analysis-1. Height and depression of the area.
2. Type of Soil.
Flow chart of methodologySatellite Data(LANDSAT)
Land Use Map
Soil map ASTERDEM
HSG Map Slope Map
SCS-CN
Topographic Maps& Collateral data
Rainfall Drainagedata Map
Map
Runoff CoefficientMap
Decision Rules forwater conservation
measures
Site Suitability Map for differentwater conservation measures
Important terms• LANDSAT-
The Landsat program is the longest running enterprise foracquisition of satellite imagery of Earth.
It has a resolution of 28.5m approx.Therefore to have precise values we will be using BHUVAN
images having resolution of 0.5-1m.
LANDSAT image of Kolkata.
• Soil Map:It determines the various types of soil in a particular area such asclayey, desert soil etc.
• Land Use Map:It shows the type of agriculture, forestry and settlement.
• ASTER DEM MAP:ASTER (Advanced Space borneThermal Emission and ReflectionRadiometer) DEM(DigitalElevation Map)
1. ASTER provides high-resolution images of the planetranging from visible to thermalinfrared light.
2. ASTER data are used tocreate detailed maps of surface
temperature of land,emissivity, reflectance, andelevation
Mt. ETNA
• HSG MAP- HYDROLOGICAL SOIL GROUPIt groups the soil of similar type.
• RUNOFF MAPThe amount of water lost due to turbulent flow.
• Land use - Land use involves the management and modificationof natural environment or wilderness into built environmentsuch as settlements and semi-natural habitats such as arablefields, pastures, and managed woods.
Land use plans are implemented through land division and useordinances and regulations, such as zoning
regulations.͞'LaŶd use' is a key terŵ iŶ the laŶguage of Đity plaŶŶiŶg.͟
• Land cover - Land cover is the physical material at the surface ofthe earth. Land covers include grass, asphalt, trees, bare ground,water, etc. Earth cover is the expression used by ecologistFrederick Edward Clements that has its closest modernequivalent being vegetation.
There are two primary methods for capturing information onland cover: field survey and analysis of remotely sensed imagery.
• Spectral Bands- For the true color rendition, band 1 is displayed in theblue color, band 2 is displayed in the green color, and band 3 is displayedin the red color. The resulting image is fairly close to realistic - as thoughyou took the picture with your camera and were riding in the satellite. Butit is also pretty dull - there is little contrast and features in the image arehard to distinguish.
Blue- Scattered by the atmosphere and illuminates material in shadowsbetter than longer wavelengths; penetrates clear water better than otherĐolors; aďsorďed ďy Đhlorophyll, so plaŶts doŶ’t shoǁ up ǀery ďrightly iŶ thisband; useful for soil/vegetation discrimination, forest type mapping, and
identifying man-made features.
Green- Penetrates clear water fairly well, gives excellent contrast betweenclear and turbid (muddy) water; helps find oil on the surface of water, andvegetation (plant life); reflects more green light than any other visible color;
man-made features are still visible.
Red- Limited water penetration; reflects well from dead foliage, but not wellfrom live foliage with chlorophyll; useful for identifying vegetation types, soils,
and urban (city and town) features .
• Geo referencing is the process of assigning spatial coordinatesto data that is spatial in nature, but has no explicit geographiccoordinate system. Here, we will take a scanned paper USGStopographic map and assign spatial coordinates to the image
so that it can be overlaid with modern data.
• Stream order is a method for classifying the relative locationof a reach within the larger river system.
Hydrologic Soil Group• Soils are classified by the Natural Resource Conservation Service into four Hydrologic Soil
Groups based on the soil's runoff potential.
• Group A is sand, loamy sand or sandy loam types of soils. It has low runoff potential andhigh infiltration rates even when thoroughly wetted. They consist chiefly of deep, well toexcessively drained sands or gravels and have a high rate of water transmission.
• Group B is silt loam or loam. It has a moderate infiltration rate when thoroughly wettedand consists chiefly or moderately deep to deep, moderately well to well drained soils
with moderately fine to moderately coarse textures.
• Group C soils are sandy clay loam. They have low infiltration rates when thoroughlywetted and consist chiefly of soils with a layer that impedes downward movement ofwater and soils with moderately fine to fine structure.
• Group D soils are clay loam, silt clay loam, sandy clay, silt clay or clay. This HSG has thehighest runoff potential. They have very low infiltration rates when thoroughly wetted andconsist chiefly of clay soils with a high swelling potential, soils with a permanent highwater table, soils with a clay pan or clay layer at or near the surface and shallow soils over
nearly impervious material.
Classification of digital imagerySupervised-
• The user selects representative samples for each land cover class inthe digital image. These sample land cover classes are called͞training sites͟. The image classification software uses the trainingsites to identify the land cover classes in the entire image.• The classification of land cover is based on the spectral signature
defined in the training set. The digital image classification softwaredetermines each class on what it resembles most in the trainingset. The common supervised classification algorithms aremaximum likelihood and minimum-distance classification.
Supervised Classification Steps:• Select training areas• Generate signature file
• Classify
Classification of digital imageryUnsupervised-
• Pixels are grouped based on the reflectance properties of pixels.These groupings are called ͞clusters͟. The user identifies thenumber of clusters to generate and which bands to use. With thisinformation, the image classification software generates clusters.There are different image clustering algorithms such as K-meansand ISODATA.• The user manually identifies each cluster with land cover classes.
It’s ofteŶ the Đase that ŵultiple Đlusters represeŶt a siŶgle laŶdcover class. The user merges clusters into a land cover type. Theunsupervised classification image classification technique is
commonly used when no sample sites exist.
Unsupervised Classification Steps:• Generate clusters• Assign classes
Rainfall Map and DataSite can be chosen when the rainfall in the area is above average. Since our area is quitesmall and has an influence of same amount of rainfall due to presence of one rain gauge
station, the factor is not to the highest importance.
Slope Map and Data
• Steep: Steeper the slope, more is the water shed.• Gentle: In gentle slope the water shed is less.
So a gentle slope is preferred to locate a catchment area.
Stream flow/ Watershed Map and Data• An area or ridge of land that separates waters flowing to different
rivers, basins, or seas is known as watershed.
2 3
1
Suitable site for Dam
Land Use/Land Cover• It is basically how the land is put into use or how has it been
covered by natural resources- agriculture, forest, water body,settlement, etc.
Unsupervised classification using iso-data
Post classification analysis
K-Mean classification- The objective of K-Mean is to minimize the withincluster variability.
Soil Type
Ideal soil conditions are as follows-
• Permeable• Compressible• Shear strength• Particle size• Specific gravity• Moisture content
Permeability Test-
Aim- To determine coefficient of permeability of soil sample.K= QL/AtH
Observation Table-Length of sample 12.73cm
C/A of sample 78.5 sq.cm
H1 20cm
H2 27cm
Area of stand pipe 1.6 sq.cm
Test temp. 33 deg C
Time interval - 7min- 5min- 5min
Coefficient of permeability 2.0917x10^-2 cm/sec
Cone Penetration Test:
Aim- To determine geotechnical properties of soil.
Observation Table-
No. Of Blows Total Blows Penetration(mm.)
0 0 25
10 10 39
10 20 53
10 30 69
10 40 78
10 50 84
Density of soil by sand replacement method
Aim- To determine the density of dry soil.
Observation Table-
Data Interpretation% Importance
distribution Requirement criteria Sub types rating Total
20 Slope Gentle 8 160
Steep 6
Land use/ Land cover30
Agriculture/Forest
Water
72709
Settlement 2
20 Rainfall Cyclonic 3 160
Orographic 8
Soil Type10
Clayey 3
Black 5 70
Loamy 7
Watershed/Stream flow20
1 9
2 7 180
3 5
Total 840
840
Conclusion
All the points that fulfill the criteria of slopes, land use/land cover,rainfall, soil type, earthquake zone, water shed and water tableare combined to get one single value criteria.
The region getting fulfilled by this criteria is the spot where thecatchment can be built.
Future Scope
This work can be carried forward by improvising all the availabledata and researching on earthquake zone and water table in theyears to come.
THANK YOU!