This presentation report focuses on the creation of hydrology of an area A geographic information system (GIS) is a system designed to capture, store, manipulate, analyze, manage, and present spatial or geographic data.

1. HYDROLOGY
Creatingdrainage networkandwatershedboundaryfromDEMdata of Trivandrum.
1. OpenDEM file fromfolderD:/Practical/DEM/tvm_dem.tif
2. OpenArcToolbox ->Spatial Analyst->Hydrology
ClickOK.

2. Select‘Flow Direction’fromHydrology.Giveinputas‘filled’andoutputas‘flow_dir’.ClickOK.
3. Select‘FlowAccumulation’fromHydrology.Give inputas‘flow_dir’andsetoutputas‘flow_acccu’.
ClickOK

3. 4. To ensure thatyour map can show the firstorderstreamswithoutbeingtoocluttered,setthe flow
accumulationtovalue asclose to that fromtoposheetaspossible. Here:
 Go to ‘Map Algebra’inSpatial Analysttoolsetandgive “Flow_acccu”> 500 (without
spaces)
Setoutputas flow_accu1

4. 
5. Open‘Streamorder’tool from‘Hydrology’toolset.
 Give inputfile as‘Flow_Accu1’,inputflow directionas‘Flow_dir’and
 Setoutputfile as‘stream_order’.
 ClickOK.Nowwe get streamorderas a rasterfile
6. To convertthe ‘stream_order’ rasterto vectorfile:
 Open‘Streamto feature’,

5.  Give inputas stream_order,inputflow directionas‘flow_dir’and
 Setoutputas ‘stream_order_v’.
 ClickOK.
7. To see the attribute fields,rightclickonthe vectorfile layerinTable of Contentspanel andselect
‘OpenAttribute table’.The Gridcode representsthe streamorder.Youcan categorize the map
accordingto streamorder bygoingto Properties ->SymbologyandcategorizingbyGridCode.

6. 8. To generate the watershedbasin,Open‘Basin’tool fromHydrologytoolsetandgive inputas
‘flow_dir’.ClickOK.