gis solutions for dredging and subsurface...

12

th Esri India User Conference 2011

GIS solutions for dredging and subsurface mapping

GIS Analyst

Infrastructure house, Shrimali Society, Beside shikhar complex,

Nr Mithakhali

Abstract: A geographic information system with specialized

applications was developed to provide baseline

information for regions including hydrographic,

topographic, subsurface information, shoreline position,

dredging records and other regional utilities, infrastructure,

and land use information. Customized GIS applications

were developed for planning and estimation of cost and

time required for a project. The GIS also incorporated

existing technology with regards to numerical models and

tools. It works as a decision making tool for d

planners.

Dredging planning is based on the behavior

subsurface soil. Borelog survey plays an important role in

dredging planning. Borelog information helps

type of dredger, rock cutters required, depth of cut and so

many other factors. Depth of cut of material is dependent

upon N value or SPT value of soil.

In the port planning, dredging is used for reclaimation of

land. Ground survey and bathymetry survey is important

after certain time interval for sedimentation analysis. GIS is

used as tool for 3 D modeling, spatial database

management , Visualization of temporal data, Production,

Cost and time estimation and for dredging planning.

GIS provides an interface to hydrographic, topographic,

historic dredge material data for a region and as well as

custom application designed to facilitate engineering

analysis. To date, development of Dredging Planning and

Estimation tool has included: input of spatial data for

dredging database management through DPRs(daily

progress reports) , Borelog and bathymetry data from

survey, use of a Arc Info and built-in tools for data

management and better visualization and display, creation

of custom application to extend the utility of Arc GIS for

required goals. This paper will give you an overview of how

one can use GIS in dredging application for data

management, dredging planning production analysis, time

and cost estimation.

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GIS solutions for dredging and subsurface mapping

Ms. Swati Singh

GIS Analyst, PMC Projects, Adani Group Infrastructure house, Shrimali Society, Beside shikhar complex,

six roads, Navrangpura, Ahmedabad-380009

A geographic information system with specialized

applications was developed to provide baseline

information for regions including hydrographic,

topographic, subsurface information, shoreline position,

dredging records and other regional utilities, infrastructure,

and land use information. Customized GIS applications

were developed for planning and estimation of cost and

The GIS also incorporated

rds to numerical models and

tools. It works as a decision making tool for dredging

behavior and type of

orelog survey plays an important role in

dredging planning. Borelog information helps to decide the

rock cutters required, depth of cut and so

many other factors. Depth of cut of material is dependent

used for reclaimation of

metry survey is important

after certain time interval for sedimentation analysis. GIS is

, spatial database

management , Visualization of temporal data, Production,

Cost and time estimation and for dredging planning.

ides an interface to hydrographic, topographic,

historic dredge material data for a region and as well as

custom application designed to facilitate engineering

development of Dredging Planning and

patial data for

dredging database management through DPRs(daily

progress reports) , Borelog and bathymetry data from

in tools for data

management and better visualization and display, creation

tend the utility of Arc GIS for

required goals. This paper will give you an overview of how

can use GIS in dredging application for data

management, dredging planning production analysis, time

About the Author:

Ms. Swati Singh,

Masters in Geology & Geoinformatics

E mail ID: [email protected]

Contact No: 09099938583

Masters in Geology & Geoinformatics

[email protected],

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Introduction

Dredging is a method of excavation in which the soil is removed from the sea bottom and is transported over water. For dredgi

activity, the subsurface information of ground to be dredged and the selection of the correct equipment play a vital role. Th

selection of appropriate dredger depends upon various factors viz. the type of soil to be dredged, the depth of dredging, the

quantity of dredged material, relocation of the dredged material at the needful place, etc. In accessing the dredging costs,

important that appropriate dredger is used for each type of soil to provide better productivity at optimised cost.

information is used to generate subsurface strata through the interpolation methods using TIN.

visualization of the subsurface which helps in analysing and providing better and detailed idea about the location.

Dredging information and management system (DIMS) provides dredger details, daily work progress, production information and

fuel consumption of every dredger that is working onsite. It works as a decision making tool for dredging planners. On the basis

of past records, they can estimate the cost and time of upcoming future dredging projects at the same location and under same

conditions.

For the development of DIMS, ArcGIS desktop has been used.

analyst, data management tool which are used for DIMS. For production analysis and dredging planning we have customised

tools in ArcGIS application.

Spatial Data Input

Spatial data that are currently included in the DIMS includes

1) Borehole data- Borelog survey records are required as input for the DIMS. The mapping of Borelog requires Borelog

database. A dataset must be interpolated on the basi

surface.

2) Hydrographic and Topographic survey data-

analyse changes in sea before and after dredging. Single beam an

Differential Global Positioning System (DGPS) data is used for topographic and ground level survey.

3) Satellite images- Geo-eye high resolution satellite images are used for mapping. These images are

projected.

4) Dredging Records-Daily dredging reports are collected from site that includes the dredger activity, production report, fuel

consumption and information about location.

5) IHC Reports- IHC Merwede provides solutions for optimum us

standard charts for certain conditions for different type of dredgers like IHC 6518, IHC 6525 and so on.

6) Landuse- With the help of high resolution satellite images and ground survey, land use featu

project the area that should be cut and filled. It also helps in laying path of floating and shore pipeline and so on.

Database Creation, Mapping and Display Using ArcGIS:

This section outlines the use of built in ArcGIS func

used in geo-database creation and data manipulation

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Dredging is a method of excavation in which the soil is removed from the sea bottom and is transported over water. For dredgi

activity, the subsurface information of ground to be dredged and the selection of the correct equipment play a vital role. Th

election of appropriate dredger depends upon various factors viz. the type of soil to be dredged, the depth of dredging, the

quantity of dredged material, relocation of the dredged material at the needful place, etc. In accessing the dredging costs,

important that appropriate dredger is used for each type of soil to provide better productivity at optimised cost.

information is used to generate subsurface strata through the interpolation methods using TIN. GIS helps in 2D and 3D

f the subsurface which helps in analysing and providing better and detailed idea about the location.


dredger that is working onsite. It works as a decision making tool for dredging planners. On the basis


desktop has been used. ArcGIS provides various in-built tools like 3D analyst, tracking


Spatial data that are currently included in the DIMS includes:

Borelog survey records are required as input for the DIMS. The mapping of Borelog requires Borelog

database. A dataset must be interpolated on the basis of borelog information using TIN (triangular irregular network)

Hydrographic and bathymetry data is required at regular time intervals to

analyse changes in sea before and after dredging. Single beam and multi-beam hydrographic instruments are used for it.

Differential Global Positioning System (DGPS) data is used for topographic and ground level survey.

eye high resolution satellite images are used for mapping. These images are geo

Daily dredging reports are collected from site that includes the dredger activity, production report, fuel

consumption and information about location.

IHC Merwede provides solutions for optimum use of dredging equipment against minimum costs. It provides


With the help of high resolution satellite images and ground survey, land use features are captured. It helps to


Database Creation, Mapping and Display Using ArcGIS:

functionality for subsurface and dredging mapping. ArcGIS and its extension is

database creation and data manipulation.

Dredging is a method of excavation in which the soil is removed from the sea bottom and is transported over water. For dredging

activity, the subsurface information of ground to be dredged and the selection of the correct equipment play a vital role. The

election of appropriate dredger depends upon various factors viz. the type of soil to be dredged, the depth of dredging, the

quantity of dredged material, relocation of the dredged material at the needful place, etc. In accessing the dredging costs, it is

important that appropriate dredger is used for each type of soil to provide better productivity at optimised cost. Borelog

GIS helps in 2D and 3D

f the subsurface which helps in analysing and providing better and detailed idea about the location.


dredger that is working onsite. It works as a decision making tool for dredging planners. On the basis


built tools like 3D analyst, tracking


Borelog survey records are required as input for the DIMS. The mapping of Borelog requires Borelog

(triangular irregular network)

Hydrographic and bathymetry data is required at regular time intervals to

beam hydrographic instruments are used for it.

geo-referenced and

Daily dredging reports are collected from site that includes the dredger activity, production report, fuel

e of dredging equipment against minimum costs. It provides


res are captured. It helps to


and its extension is

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Subsurface Mapping– Subsurface mapping is based on borelog data and borelog mapping. The borelog mapping is performed in

two steps. The first step is the database creation and second is the display of data in desired form. Thereafter, Borelog data

captured from ground survey and uploaded on geo

understanding, borelog 3Dmapping is done with the help of ArcScene.

Using interpolation method and borelog data, virtual soil surface is generated, which provides a real 3D view of the surface

present beneath the sea and provides valuable underground information. It wo

makers to decide which area to be dredged and thereby helping in optimising the project cost.

Dredging Mapping- Daily progress reports of various dredgers is collected from site on regular basis and it has been updated on

dredging geo-database. ArcGIS tracking analyst extension

planners for planning and calculating cost and time of projects.

Performed Analysis

Based on past 5 year’s experiences and records, an analysis is performed. This analysis helps in evaluating the standard

performance that can be expected from existing dredgers under varying conditions. Various factors which impact the production

level of dredgers on daily basis are incorporated in the software for better and actual approximation of the project cost and time

required henceforth. These factors are stated as follows:

• Material Type- The material type is generally classified on the basis of grain size, type and com

• Discharge Distance- Discharge distance is defined as the distance at which the dredged material is disposed. It includes

floating pipeline and shore pipeline.

• Unhindered dredging- Continuous dredging and pumping is required for hi

• Dredger Movement and depth of cut- Depth of cut and dredger movement have a great impact on the production ate of

dredgers. Depth of cut is defined as the depth of material being dredged at the designated area. With shallow depth of

cut, dredger shifting/movement increases. Thus, production per hour reduces.

• Original Condition of pump and pump parts

Hence a correction factor is incorporated on the basis of time lag

pump parts.

• Bends in pipeline (FPL & SPL)- Bends in FPL depends on the project site conditions. The number of Bends present in the

pipeline is directly proportional to the resistance to the flow of mat

choke the pipeline while passing through the bend and hence greater power and capacity is required to pump to the

discharge end.

• Geodetic Head- Geodetic head is the height of shore pipeline take

• Out of the above mentioned factors, the two that are most important and have a prominent effect on production rate

are material type and discharge distance.

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Subsurface mapping is based on borelog data and borelog mapping. The borelog mapping is performed in

steps. The first step is the database creation and second is the display of data in desired form. Thereafter, Borelog data

captured from ground survey and uploaded on geo-database. For better visualisation and to provide a better sense of

orelog 3Dmapping is done with the help of ArcScene.


present beneath the sea and provides valuable underground information. It works as an input for DIMS and helps decision

makers to decide which area to be dredged and thereby helping in optimising the project cost.

Daily progress reports of various dredgers is collected from site on regular basis and it has been updated on

extension helps to keep track on records of all the dredgers. It helps dredging

ning and calculating cost and time of projects.

experiences and records, an analysis is performed. This analysis helps in evaluating the standard


s are incorporated in the software for better and actual approximation of the project cost and time

required henceforth. These factors are stated as follows:

The material type is generally classified on the basis of grain size, type and compactness of the material.

Discharge distance is defined as the distance at which the dredged material is disposed. It includes

Continuous dredging and pumping is required for higher production rate.

Depth of cut and dredger movement have a great impact on the production ate of


cut, dredger shifting/movement increases. Thus, production per hour reduces.

Original Condition of pump and pump parts- With aging of pump and pump parts, efficiency of the pump decreases.

Hence a correction factor is incorporated on the basis of time lag that is actually present because of wearing pump and

Bends in FPL depends on the project site conditions. The number of Bends present in the

pipeline is directly proportional to the resistance to the flow of material. Dredged material being a slug material, might


Geodetic head is the height of shore pipeline take-off point from water level.

Out of the above mentioned factors, the two that are most important and have a prominent effect on production rate

material type and discharge distance.

Subsurface mapping is based on borelog data and borelog mapping. The borelog mapping is performed in

steps. The first step is the database creation and second is the display of data in desired form. Thereafter, Borelog data

database. For better visualisation and to provide a better sense of


rks as an input for DIMS and helps decision

Daily progress reports of various dredgers is collected from site on regular basis and it has been updated on

helps to keep track on records of all the dredgers. It helps dredging

experiences and records, an analysis is performed. This analysis helps in evaluating the standard


s are incorporated in the software for better and actual approximation of the project cost and time

pactness of the material.

Discharge distance is defined as the distance at which the dredged material is disposed. It includes

Depth of cut and dredger movement have a great impact on the production ate of


With aging of pump and pump parts, efficiency of the pump decreases.

that is actually present because of wearing pump and

Bends in FPL depends on the project site conditions. The number of Bends present in the

erial. Dredged material being a slug material, might


Out of the above mentioned factors, the two that are most important and have a prominent effect on production rate

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Dredge productivity

Dredge productivity can be estimated by following ways:

• By analyzing the capabilities of the dredger on current location and then comparing the performance of the same

dredger on a different site but having the same project conditions.

• By reference to similar projects in the past i.e. on the

• By combining the above mentioned factors

Theoretical Performance

Various tests are being performed by the dredge building companies to analyze the standard performance of dredgers. These

tests are performed under various ideal conditions to know and analyse the workability range of the dredgers. With our 65 series

and 75 series dredgers being IHC built, we have production graph provided by IHC.

Table 1: Ideal Conditions under which dredger graph is pre

Criteria/Parameter

Original condition of Pump & Part

Dredging Depth

Depth of Cut

Continuous dredging time

Pumping Distance

Floating Pipeline Length

No of bends in Pipeline

Geodetic Head

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following ways:

the capabilities of the dredger on current location and then comparing the performance of the same

dredger on a different site but having the same project conditions.

By reference to similar projects in the past i.e. on the basis of past records.

By combining the above mentioned factors- Using ‘extend’ references


rmed under various ideal conditions to know and analyse the workability range of the dredgers. With our 65 series

and 75 series dredgers being IHC built, we have production graph provided by IHC.

Table 1: Ideal Conditions under which dredger graph is prepared

Standard

Newly Built dredgers are Tested

-18mCD

1.5 to 2m

4 hours continuous Dredging(without hindrance)

2000m

Not more than 500m

Only 1 bend in FPL, with not less than 45

4m

the capabilities of the dredger on current location and then comparing the performance of the same


rmed under various ideal conditions to know and analyse the workability range of the dredgers. With our 65 series

4 hours continuous Dredging(without hindrance)

Only 1 bend in FPL, with not less than 45

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Figure 1: Production Graph Provided by IHC

However, in our projects, the conditions depend on different project sites and project

FPL and SPL, Depth of Cut, Hindrances (like tree stumps, debris, and ship movements and traffic etc.). So incorporating all t

factors along with the ideal case results, we can calculate the actual efficiency an

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Figure 1: Production Graph Provided by IHC

However, in our projects, the conditions depend on different project sites and project requirements such as FPL length, Bends in

FPL and SPL, Depth of Cut, Hindrances (like tree stumps, debris, and ship movements and traffic etc.). So incorporating all t

factors along with the ideal case results, we can calculate the actual efficiency and workability of dredgers.

requirements such as FPL length, Bends in

FPL and SPL, Depth of Cut, Hindrances (like tree stumps, debris, and ship movements and traffic etc.). So incorporating all these

d workability of dredgers.

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Table 2:A comparison of practical condition at our project sites with ideal conditions

Criteria/Parameter Ideal Conditions

Original condition of Pump and

Part

Dredgers are tested

pumps

Depth of Cut 1.5 to 2m

Continuous Dredging time 4 hr

Pumping Distance 2000m

Floating Pipeline Length Not more than 500m

No. Of Bends in Pipeline (Both FPL

& SPL)

Only 1 bend, with not less than 45

Geodetic Head 4m

Customized tool in ArcGIS for DIMS

GIS acts as a tool in DIMS and it designed to provide quick and fast results /output, under all the

There are two customized tools for DIMS. First being the Productivity Estimation tool. It gives the information about production

rate of a dredger with respect to the change in discharge distance. And second being the Time Estimation

how much time is required to reclaim the target area.

Productivity Estimation tool

For the customization of this tool following parameters are considered:

• Type of Dredger

• Dredger Model

• Rock Density

• Rock type

• N value of rock

• Depth of Cut

• Discharge Length

• Pumping Capacity

• No of bends

• Dredging Time

• Geodetic Head

It requires discharge distance as an input from user. Depending upon the model

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Ideal Conditions Practical conditions in our projects

Dredgers are tested with new

pumps

Pump, Pump parts are used till

replacement is required, high wear

& tear

1.5 to 2m Depends on project design.

Desilting, sweeping etc. Activities

need very shallow depth of cut

(max 0.5m)

4 hr continuous dredging Frequent breakdowns, anchor

shifting, traffic, hindrance, site

constraints etc. May not allow long

periods of continuous dredging.

2000m May vary based on priorities of

dredging &reclamation as per

project requirements

Not more than 500m Generally ranges from 400 m to

1000m, based on project

requirements.

Only 1 bend, with not less than 45 Depends on traffic & movements,

site restrictions, Dredging &

reclamation plan, other project

activities (likely jetty construction

etc.)

4m Goes up to 9m

GIS acts as a tool in DIMS and it designed to provide quick and fast results /output, under all the practical conditions.

tools for DIMS. First being the Productivity Estimation tool. It gives the information about production

rate of a dredger with respect to the change in discharge distance. And second being the Time Estimation Tool. It calculates that

how much time is required to reclaim the target area.

For the customization of this tool following parameters are considered:

user. Depending upon the model it calculates the productivity rate of dredger.


Practical conditions in our projects

Pump, Pump parts are used till

replacement is required, high wear

Depends on project design.

Desilting, sweeping etc. Activities

need very shallow depth of cut

Frequent breakdowns, anchor

shifting, traffic, hindrance, site

constraints etc. May not allow long

periods of continuous dredging.

May vary based on priorities of

dredging &reclamation as per

project requirements.

Generally ranges from 400 m to

1000m, based on project

Depends on traffic & movements,

site restrictions, Dredging &

reclamation plan, other project

activities (likely jetty construction

practical conditions.

tools for DIMS. First being the Productivity Estimation tool. It gives the information about production

Tool. It calculates that

it calculates the productivity rate of dredger.

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Time Estimation Tool

For evaluating this tool we require two inputs from user. First is the volume required to reclaim the area of interest, the volume

is indeed obtained from the ‘cut fill analysis’ and the second input is the productivity rate of the dredger that is obtained

the above mentioned productivity estimation tool.

Methodology

Currently Mundra Port has dredgers, along with off

goal is to achieve optimum dredging production and operating costs that will meet the project requirements as planned and

desired by the management.

Work Flow

Following steps are involved to get desired output from

• 3D Mapping of borelog data: Borelog data is collected and mapped 3Dimensionally to prepare grounds for performance

of subsurface mapping.

• Subsurface mapping with the help of borelog information and

Figure 2: Showing 3D Mapping of borelogs

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s tool we require two inputs from user. First is the volume required to reclaim the area of interest, the volume

is indeed obtained from the ‘cut fill analysis’ and the second input is the productivity rate of the dredger that is obtained

ntioned productivity estimation tool.

dredgers, along with off –shore support resources as well as onshore support resources. The Ultimate


get desired output from ArcGIS:

: Borelog data is collected and mapped 3Dimensionally to prepare grounds for performance

Subsurface mapping with the help of borelog information and ArcGIS functionalities.

Figure 2: Showing 3D Mapping of borelogs,dredginglines and subsurface

s tool we require two inputs from user. First is the volume required to reclaim the area of interest, the volume

is indeed obtained from the ‘cut fill analysis’ and the second input is the productivity rate of the dredger that is obtained from

shore support resources as well as onshore support resources. The Ultimate


: Borelog data is collected and mapped 3Dimensionally to prepare grounds for performance

and subsurface

12


Figure 3: Showing Borelog Data W

• Dredging Material is used to raise ground level or reclamation purpose. In the project where high ground level is

required, dredging material is used for that.

• For reclamation first we require cut-fill volume of that location. It could be obtained by

Use of Productivity Estimation Tool:

Figure 4: It requires discharge distance from user as inpu

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Figure 3: Showing Borelog Data Window on Clicking the desired Borelog

is used to raise ground level or reclamation purpose. In the project where high ground level is

required, dredging material is used for that.

fill volume of that location. It could be obtained by ArcGIS built in tools

t requires discharge distance from user as input. It is a variable parameter. On the click of button it ask

for material density .

layer

is used to raise ground level or reclamation purpose. In the project where high ground level is

built in tools.

n the click of button it ask

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Figure 5: The output(productivity rate)

Use of Time Estimation Tool

Figure 6: The output in days i.e. 87

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: The output(productivity rate) as shown after computation to be 250 (cu. Meter /hour)

density input from the user.

i.e. 87 days that is being evaluated after providing the fill volume and production

rate

r computation to be 250 (cu. Meter /hour) after providing

fill volume and production

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Conclusion

It can be concluded that after preparing the database, doing cut fill analysis, choosing the pipe length for dredged material (b

onshore and off shore),dredger type and entering the density of dredged material i.e. 2200 kg/m3 here, we get the production

rate to be 250 cubic meter/hour. From this production rate we obtained the fill volume to be 313411 cubic meter and further

time estimation tool gives the value to be 87days.

This data is useful for dredger planners in computing the dredger efficiency, accuracy output and to schedule accordingly the

location of dredger at different sites after getting to know the amount of time that could be spent by a single dredge

particular location.

References

• Nil Guler, "Evaluation of port development projects by the benefit cost analysis" ,December2003.

• Report on "Understanding dredging production and cost"

• Greg Farnham "Comparative cost analysis and considerations of s

• Teresa M. Adams "GIS based Subsurface data management", November2008.

• James D. McCarthy,Phil A. Graniero ,"A GIS

system",december2006.

of 10

can be concluded that after preparing the database, doing cut fill analysis, choosing the pipe length for dredged material (b

and entering the density of dredged material i.e. 2200 kg/m3 here, we get the production

From this production rate we obtained the fill volume to be 313411 cubic meter and further

days.


location of dredger at different sites after getting to know the amount of time that could be spent by a single dredge

Nil Guler, "Evaluation of port development projects by the benefit cost analysis" ,December2003.

Report on "Understanding dredging production and cost"

Greg Farnham "Comparative cost analysis and considerations of sediment dredging", Febuary2010.

GIS based Subsurface data management", November2008.

,"A GIS-based borehole data management and 3D visualization

can be concluded that after preparing the database, doing cut fill analysis, choosing the pipe length for dredged material (both

and entering the density of dredged material i.e. 2200 kg/m3 here, we get the production

From this production rate we obtained the fill volume to be 313411 cubic meter and further


location of dredger at different sites after getting to know the amount of time that could be spent by a single dredger at a

Nil Guler, "Evaluation of port development projects by the benefit cost analysis" ,December2003.

ediment dredging", Febuary2010.

based borehole data management and 3D visualization

gis solutions for dredging and subsurface...

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