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Integrated Coastal Zone Management - Coastal Hazard Line Mapping By M Dharma Raj Addl. S.G , SZ & ICZM Project Director Survey of India. Coastal Hazard Line demarcation & Integrated Coastal Zone Management Based on established scientific principles. - PowerPoint PPT Presentation
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Coastal Hazard Line demarcation
& Integrated Coastal Zone Management
Based on established scientific principles
Demarcation of a VulnerabilitySetback / Hazard line.
Setback line is the boundary line beyond which the effect of Natural Hazards such as erosion and sea-level-rise will not be felt.
The parameters involved are: Elevation, sea-level-rise & Coastal Erosion.
Elevation: DEM will be generated by Photogrammetry.
Sea-Level Rise: Tidal data will be processed to compute the 100 year Return Period Extreme Tidal Height values at any Transect point using Weibull Distribution and Linear Interpolation.
Coastal Erosion: Annual Rate of Coastal Erosion will be Computed by comparing the oldest Topo-Map and the Latest Aerial Photography Ortho / satellite Image and extrapolated to next 100 years.
Fresh Aerial Photography” with 9 cm gsd using Digital Aerial Camera.
Primary Ground Control. Block Control Control extension -
Photogrammetry. AT & Block adjustment. DEM Collection at 5m Grid. Ortho & Feature Collection
Use extreme elevation data of 100 year return period at 20 major and 250 minor ports computed by G & RB, SOI.
Interpolate at other Transect points using linear interpolation.
Transfer these heights to the DEM and join the line.
This will give the flood line.
Compute rate of coastal erosion at every 500 m transect point using old Topo Sheet and new satellite image / ortho photo data.
Extrapolate for 100 year return interval using linear extrapolation.
This line represents coastal erosion line.
The final Hazard Line Is the most landward of the Flood Line & Erosion Line. Delineate the same In a GIS Environment. Mark on Ground with pillars / markers.
EROSION LINE
Max Flood line
SEA AREA
Land
HAZARD LINE
Coastal States
a)LevellingEstablish BMs & BCP (heights)
b)Establishment of Primary GCPsc)Establishment of Secondary GCP and BCP
(Horizontzl)d)Aerial Photography
QA/QC proceduresPhotographyStatutory clearances
e)Photogrammetry and Map Data generation Aerial Triangulation (AT) Digital Elevation Model (DEM) and
Contour generation Ortho-rectification
f) Tidal Data Analysis Computation of 100 year Return
Period Flood Line.g)Erosion Data Analysis
Computation of 100 year Return Period Erosion Line.
g)Mapping the final Hazard Line Most Landward of Flood Line /
Erosion Line.
h)Demarcation of Hazard Line Fixing of Markers/ Pillars
Aerial Photography & Preliminary AT/DEM/Ortho.
Rigorous Photogrammetric Survey.
Quality Control at various stages.
Provision of Ground Control Points
BySurvey of India
Primary Control
Secondary Control
High PrecisionDouble TertiarySingle TertiaryStability CheckLinear AdjustmentAlong The Flight LinePost pointing of Staff Positions to serve as
Check Points.
DT LevellingDT LevellingNo of LinesNo of Lines 22 Length Length 1860018600 KmKm
ST LevelingST LevelingNo of Lines (No. No of Lines (No. of Strips +1)of Strips +1) 99 Length (6 Lines)Length (6 Lines) 8370083700 KmKmTotal Length of Total Length of Level LinesLevel Lines 102300102300 kmkm
Principle of Whole To Part
Leap Frog Method
Least Square Adjustment Carrier Phase
Relative Positioning (Phase Difference)
Static Mode
Loop Closure
Positional Accuracy 2 Cm
GPS
Radial Line Method
Loop Closure Check
Positional Accuracy 4
Cm
Planning
Adjustment
DEM
No. of Mass Points 1,736,000,000
Break lines 50%Total Height Total Height PointsPoints 2,604,000,0002,604,000,000
Density of Mass Point@ 5 m
Omission of Break lines
Checking of TIN
Most vital component of this Project.
Photography is just a means to the end.
Its specifications have been designed to meet the end-product
gsd 9 cmDesigned to maximize its utility in Photogrammetric Processes
Acquisition RequirementsPlatformCamera
MountsCertification
Flight Plan and Coverage ( http://www.moef.nic.in)Flying Conditions
Image RequirementsSpatial ResolutionSpectral ResolutionRadiometric Resolution
Control RequirementsPre-pointed ControlDifferential GPS/GNSS & IMU ControlGround Stations
GPS Control for horizontal control (1st Order)Levelling Heights for vertical control (H.P BMs)
Quality Control
Closely Managed Processes with built-in Closely Managed Processes with built-in Quality ChecksQuality Checks
DocumentationDocumentation Standard Operation ProceduresStandard Operation Procedures Work FlowsWork Flows
Quality Checks at each stageQuality Checks at each stage GCP Control (Plan & Height) – Rigorous Deptt. GCP Control (Plan & Height) – Rigorous Deptt.
standardsstandards Flight Planning - ApprovalFlight Planning - Approval Flight Execution & Monitoring (Differential GPS and Flight Execution & Monitoring (Differential GPS and
IMU)IMU) Flight Evaluation – Corrective action while Flight Evaluation – Corrective action while
resources still at siteresources still at site Go ahead approval.Go ahead approval.
Quality Control RecordsQuality Control Records
Preliminary AT/Ortho-Preliminary AT/Ortho-rectification rectification (FULL PROOF QA/QC )with (FULL PROOF QA/QC )with minimum effort and gestation lag)minimum effort and gestation lag) Suitability for Photogrammetric Suitability for Photogrammetric
Processes,Processes, check for Direct Sensor check for Direct Sensor
Orientation, Orientation, Pre-pointed controls, Pre-pointed controls, overlaps & gaps overlaps & gaps
Measurement and certification Measurement and certification of work also based on of work also based on Preliminary OrthoPreliminary Ortho
Sea Level Rise / Flood Line Mapping
Flood Line MappingInput
100 year return period elevations of 20 primary ports.
Data of about 250 secondary ports.
0.5m contours / DEM. Ortho aerial image.
Interpolation Of Return Period Tidal Elevations
Compute 100 year Return Period Max Compute 100 year Return Period Max Elevations values at each of the 20 primary Elevations values at each of the 20 primary ports.ports.
Compute 100 year Return Period values at Compute 100 year Return Period values at each of the 250 Secondary Port using 2 each of the 250 Secondary Port using 2 neighboring primary portsneighboring primary ports
This will give 100 year RPs at about every 30 This will give 100 year RPs at about every 30 km.km.
Draw a base line for measurements and make Draw a base line for measurements and make
Transects at every 500 m.Transects at every 500 m.
Linearly Interpolate at Transect points using 2 Linearly Interpolate at Transect points using 2 neighboring Primary / Secondary ports.neighboring Primary / Secondary ports.
Interpolation Of Return Period
Primary Ports Secondary Ports
Transect Points
Survey of India is one of the premier organizations in the world having more than 130 years of expertise in tidal data acquisition.
It is a large store house of tidal data , collected
from major part of its area of responsibility.
Presently Survey of India is maintaining a huge network of permanent tidal stations , located along the Indian Coast and Islands.
These tidal stations are equipped with state-of-the-art digital tide gauges , co-located with dual frequency GPS receivers and real time data transmission facilities through dedicated VSAT network.
Estimated tidal heights for 100 years return period have been determined for the ports having tidal records for at least 10 years. 20 such tidal stations have been identified in the east and west coast for determining the tidal level for 100 years return period.
i. Provide minimum 10 years of historical tide gauge data for all ports within the state boundary for which long term observations are available.
ii. Determine the Annual Maximum Water Level for each year and each port.
iii. Reduce Annual Maxima from Chart Datum to IMSL and tabulate.
iv. Rank order the datav. Calculate Weibull distribution and plotting positions of
all the available data.vi. Fit regression line to plotted data and extrapolate to
100 years.vii. Calculate the tidal heights for 100 years return period.
Interpolation Of Return Period At Minor Ports 100 years Return Period for major port M1 (Known Station) = 5.89 m 100 years Return Period for major port M2 (known Station) = 4.80 m
Distance between M1 & M2 = 47.52 km Distance between M1 and Secondary port S = 21.46 km
Indirect Interpolation: Tidal Ht. for 100 year RP-HAT of M1=5.8900-4.5051 = 1.3849 Tidal Ht. for 100 year RP-HAT of M2 =4.8000-4.0379 = 0.7621
Correction for S = 1.3849+{(0.7621-1.3849)*Distance from M1 (21.46)}/Total Distance(47.52)
=1.1036 m100 years Return Period for S = HAT of S + Correction =
4.2351+1.1036 = 5.3387 m
100 years Return Period Calculated by Indirect interpolation = 5.3387 m5.3387 m
5.89 m
4.80m
47.52 km
HAT = 4.5051 m
HAT = 4.0379 m
RP - HAT = 1.3849 m
RP - HAT = 0.7621 M
DIFFERENCE IN RP-HAT = 0.6228 m
Completeness of Tidal Data ….. Completeness of Tidal Data …..
• All available Data up to 2010 will be used All available Data up to 2010 will be used after checking for quality.after checking for quality.
• Month-wise distribution / availability of data Month-wise distribution / availability of data will be checked.will be checked.
• Regularity of Missing Data will also be Regularity of Missing Data will also be checked.checked.
• Tsunami / Cyclone data will also be included.Tsunami / Cyclone data will also be included.
INDIAN MEAN SEA LEVEL (IMSL)
HEIGHT OF TIDE ABOVE CD
HEIGHT OF TIDE ABOVE IMSL
CHART DATUM (CD)
Converting Chart Datum IMSL
Linear Interpolation at Transect Linear Interpolation at Transect PointsPoints
Two ports ( primary / secondary) will be taken
at a time: (x,y) (x,y) (x2,y2)(x2,y2) (y - y1) (y - y1) ΔΔy y ( x1,y1) (x-x1) ( x1,y1) (x-x1) ΔΔx x
(y - y1) / (x-x1) = ((y - y1) / (x-x1) = (ΔΔy/y/ Δ Δx)x)
Based on Equation of line or SimilarTriangles y = y1 + (y = y1 + (ΔΔy/y/ Δ Δx)(x-x1)x)(x-x1)
Erosion Line Mapping.
Required inputs:Required inputs:- Multiple shoreline positions- Multiple shoreline positions- User-generated baseline- User-generated baseline
Transects For Erosion Line Mapping.
DSAS generates transects that are cast perpendicular DSAS generates transects that are cast perpendicular to the baseline at a user-specified spacing alongshore.to the baseline at a user-specified spacing alongshore.
The transect/shoreline intersections along this baseline The transect/shoreline intersections along this baseline are then used to calculate the rate-of-change statistics.are then used to calculate the rate-of-change statistics.
Project DeliverablesProject Deliverables
DEM: DEM: GridGrid 5 m5 mOrtho-Rectified Photographs Ortho-Rectified Photographs 1:100001:10000 ScaleScaleHazard Line Marked on the Ortho-Rectified PrintsHazard Line Marked on the Ortho-Rectified PrintsHazard Line demarcated on the groundHazard Line demarcated on the groundSymbolized Vector Data:Symbolized Vector Data: Features:Features: Village Boundary Polygon with NameVillage Boundary Polygon with Name Village Roads and aboveVillage Roads and above All NamesAll Names Other Major Feature such as Other Major Feature such as
Rivers, Lakes, Sea, Railway lines, Canals Rivers, Lakes, Sea, Railway lines, Canals etcetc
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