Bathymetry User Guide · Web viewProvincial Mapping Unit Mapping and Information Resources Branch...

User Guidefor

BathymetryLIO Data Classes

Provincial Mapping UnitMapping and Information Resources Branch

Corporate Management and Information DivisionMinistry of Natural Resources and Forestry

2023-09-20

Disclaimer

This technical documentation has been prepared by Her Majesty the Queen in right of

Ontario as represented by the Ministry of Natural Resources and Forestry (the

“Ministry”). No warranties or representations, express or implied, statutory or otherwise

shall apply or are being made by the Ministry with respect to the documentation, its

accuracy or its completeness. In no event will the Ministry be liable or responsible for

any lost profits, loss of revenue or earnings, claims by third parties or for any economic,

indirect, special, incidental, consequential or exemplary damage resulting from any

errors, inaccuracies or omissions in this documentation; and in no event will the

Ministry’s liability for any such errors, inaccuracies or omissions on any particular claim,

proceeding or action, exceed the actual consideration paid by the claimant involved to

the Ministry for the materials to which this instructional documentation relates. Save and

except for the liability expressly provided for above, the Ministry shall have no

obligation, duty or liability whatsoever in contract, tort or otherwise, including any liability

or negligence. The limitations, exclusions and disclaimers expressed above shall apply

irrespective of the nature of any cause of action, demand or action, including but not

limited to breach of contract, negligence, strict liability, tort or any other legal theory, and

shall survive any fundamental breach or breaches.

Cette publication spécialisée n’est disponible qu’en anglais.

Additional Information

For more information about this document, please contact the Provincial Mapping Unit

at [email protected].

© 2019, Queen’s Printer for Ontario 2

mailto:[email protected]

Executive Summary

Key Words

Bathymetry, Contour, Depth, Elevation, Fish, Fishing, Hydrogeology, Hydrology, Lake,

Lakes, Underwater, Water

Abstract

This user guide details the specifications for the Historic Bathymetry Maps, Bathymetry

Index (BATHYMIX), Bathymetry Line (BATHYML), and Bathymetry Point (BATHYMP)

Land Information Ontario (LIO) Data Classes.

3

Table of Contents

Disclaimer........................................................................................................................2Additional Information......................................................................................................2Executive Summary.........................................................................................................3

Key Words.....................................................................................................................3Abstract.........................................................................................................................3

Table of Contents.............................................................................................................4List of Figures...................................................................................................................5List of Acronyms...............................................................................................................61. Introduction..................................................................................................................72. Objectives....................................................................................................................73. Historic Bathymetry Maps............................................................................................84. Data Classes: Bathymetry............................................................................................8

4.1 Bathymetry Index (BATHYMIX)...............................................................................84.2 Bathymetry Line (BATHYML)..................................................................................84.3 Bathymetry Point (BATHYMP)................................................................................9

5. Model Diagram: Bathymetry Data Classes................................................................106. Data Description.........................................................................................................11

6.1 BATHYMETRY_INDEX_FT..................................................................................116.2 BATHYMETRY_LINE_FT.....................................................................................136.3 BATHYMETRY_POINT_FT..................................................................................14

7. Links to Additional Information...................................................................................17APPENDIX A: LIO Lookup Tables and Values..............................................................18

LOCATION_ACCURACY_LIST..................................................................................18APPENDIX B: Table Key Dependency and Relationship Index.....................................20

Lookup Table Indexes.................................................................................................22

4

List of Figures

Figure 1: Primary Key example......................................................................................20

Figure 2: Foreign Key example......................................................................................20

Figure 3: Alternate Key example....................................................................................20

Figure 4: Example of an Identifying Relationship...........................................................21

Figure 5: Example of a Non-identifying Relationship.....................................................21

Figure 6: Model Diagram Relationship Symbology Table..............................................21

5

List of Acronyms

GIS: Geographic Information System

GPS: Global Positioning System

LiDAR: Light Detection and Ranging

LIO: Land Information Ontario

LUT: Lookup Table

MNRF: Ontario Ministry of Natural Resources and Forestry

OGF: Ontario Geospatial Feature

OHN: Ontario Hydro Network

6

1. Introduction

Between 1948 and 1995 the Ontario Ministry of Natural Resources and Forestry

(MNRF) captured bathymetry data for over 11,000 lakes across Ontario.

The historic bathymetry maps were created using simple methods to determine lake

depths and were meant for resource management purposes only. Very little effort was

made to identify shoals and other hazards when creating these bathymetric maps.

Since the data was collected constructed and naturally occurring events may have

resulted in the depth information becoming inaccurate.

In many cases, these maps still represent the only authoritative source of bathymetry

data for lakes in Ontario. These maps are being converted to digital GIS line data which

can be found in the Bathymetry Line data class. The Bathymetry Index data class

identifies whether a Historic Map exists and whether GIS vector lines have been

created.

More recent bathymetric data has been collected using sonar and Global Positioning

System (GPS) technology. This modern technique creates lake depth points (spot

depths) rather than contours. This point data is stored in the Bathymetry Point data

class.

The data can be used for the purposes of fish monitoring and other ecological

applications, watershed-based water budgeting, hydrologic cycle modelling, climate

change modelling and by the general public.

Bathymetry maps and data should not be used for navigational purposes. For more

information visit Land Information Ontario (https://www.ontario.ca/page/land-

information-ontario).

2. Objectives

This guide is intended for users with a general interest in the Bathymetry LIO Data

Classes. The remainder of this document describes the extent and context of the

information collected for the data class.

7

https://www.ontario.ca/page/land-information-ontario

3. Historic Bathymetry Maps

The majority of the historic paper maps have been scanned to digital files. Digital files

will be added to this dataset when they become available. The digital files have been

grouped and packaged by regions into several compressed (zipped) files for download.

Visit the official LIO metadata record for Historic Bathymetry Maps for a map of the

download regions, lake name lookup table, and to download data packages.

4. Data Classes: Bathymetry

The Bathymetry Information Class is made up of three bathymetry-themed data classes.

4.1 Bathymetry Index (BATHYMIX)

The Bathymetry Index contains polygons representing the boundaries of all lakes that

have bathymetry populated in the Bathymetry Line and Point data classes or a Historic

Bathymetry Map. Limited metadata information unique to each lake such as the survey

year, survey method and scale of original map is included with the polygons. The

polygons have been copied from OHN Waterbody but do not necessarily represent the

actual extent of bathymetric mapping within a given lake (bathymetric mapping could be

larger or smaller than polygon extents).

4.2 Bathymetry Line (BATHYML)

Bathymetry Line contains lines of constant depth called depth contours or isobars.

Depth contours are used to portray the terrain relief below the surface of the water.

The data used to derive the depth contours are always spot depths, but the density and

positional accuracy of these spot depths vary depending on the survey style and

parameters. Before GPS data was available, spot depth locations were derived by

straight line transects across a water body which were then plotted on a map. The time-

consuming nature of this method limited the number of transects collected. Now GPS

data collection is not limited to transects and therefore spot depth collections tend to be

far denser with greater horizontal and vertical accuracy.

8

Depth contours have been derived in one of two ways:

1. Visually interpreted and drawn by hand based on transects of the water body

2. Interpolated using GIS processes such as Kriging or Natural Neighbours

Vertical accuracy of the data varies greatly depending on the density of spot depth

collected for each lake. Horizontal accuracy will also vary greatly on older transect

based collections but will be within 5m for GPS based collections.

4.3 Bathymetry Point (BATHYMP)

Bathymetry Points indicate the measurement of water depth at various places in a body

of water and are often called spot depths.

The data in this layer has primarily been collected using a depth measurement device,

such as an echo-sounder, in combination with a GPS for horizontal positioning.

However, other survey methods such as bathymetric LiDAR may also have been used.

Please see the Bathymetry Index layer for the survey method used in each water body.

The points in this layer are the source data for all bathymetric data and should be used

(when available) for the creation of bathymetric derivative products such as rasters,

TINs and depth contours. Point densities will vary by water body and within water

bodies, depending on the parameters or the survey.

9

5. Model Diagram: Bathymetry Data Classes

Physical Model Diagram for:Bathymetry Index (BATHYMIX) v2Model Effective Date 2019-AUG-07

Bold = New Column

BATHYMETRY_INDEX_FTOGF_ID NUMBER(13) NOT NULLPROJ ECT_NAMEWBY_LIDSURVEY_YEARSCALE_TEXTSURVEY_METHODBATHYMETRY_LINE_INDBATHYMETRY_POINT_INDHISTORIC_MAP_INDGEOMETRY_UPDATE_DATETIMEEFFECTIVE_DATETIMESYSTEM_DATETIMESHAPE

VARCHAR2(100) VARCHAR2(13) NUMBER(4) VARCHAR2(30) VARCHAR2(8) VARCHAR2(3) VARCHAR2(3) VARCHAR2(3) DATE DATE DATE SDO_GEOMETRY

NULL NOT NULL NULL NULL NOT NULL NOT NULL NOT NULL NOT NULL NULL NOT NULL NOT NULL NULL

10

11

12

6. Data Description

The main business area table(s) for this model can be found below. Associated lookup tables will be listed in Appendix A of this document and are hyperlinked

where referenced in this section.

6.1 BATHYMETRY_INDEX_FT

A spatial index (polygon) identifying water bodies in Ontario that have bathymetric data available through Land Information Ontario.

Column Name Column Type Mandatory Short Name Description

OGF_ID NUMBER(13) Yes OGF_ID Ontario Geospatial Feature (OGF) system generated identifier, unique at the application level.

PROJECT_NAME VARCHAR2(100) No PROJ_NAME The name of the bathymetry project.

WBY_LID VARCHAR2(13) Yes WBY_IDA reference to the Waterbody ID found in the Geographic Named Extent (GEL) layer. The Waterbody ID is a unique waterbody identifier (ZZ-EEEE-NNNNN) based on UTM of centroid.

SURVEY_YEAR NUMBER(4) No SURVEY_YR The year when the most recent bathymetric lake survey was completed.

SCALE_TEXT VARCHAR2(30) No SCALE_TEXT The original scale text from the source bathymetric map. For example, 8 inches = 1 mile.

SURVEY_METHOD VARCHAR2(8) Yes SURV_MTHD

The method used to collect the bathymetric information.VALID VALUES:

GPS

Transect

Other

13


BATHYMETRY_LINE_IND VARCHAR2(3) Yes LINE_IND

Indicates if bathymetry data is available as an interpolated contour.VALID VALUES:

Yes

No

DEFAULT: 'No'

BATHYMETRY_POINT_IND VARCHAR2(3) Yes POINT_IND

Indicates if bathymetry data is available as points.VALID VALUES:

Yes

No

DEFAULT: 'No'

HISTORIC_MAP_IND VARCHAR2(3) Yes MAP_IND

Indicates if a scanned historic bathymetry map is available.VALID VALUES:

Yes

No

DEFAULT: 'No'GEOMETRY_UPDATE_DATETIME DATE No GEO_UPT_DT Date/time the geometry was created or last modified in the source

database.EFFECTIVE_DATETIME DATE Yes EFF_DATE Date/time that the record was created in the database

SYSTEM_DATETIME DATE Yes SYS_DATEDate/time the record was loaded into or last modified in the LIO database.DEFAULT: SYSDATE

SHAPE SDO_GEOMETRY No SHAPE Spatial Data Option (SDO) Geometry object.

14

6.2 BATHYMETRY_LINE_FT

A continuous line formed of vertices indicating the same measurement of water depth at various places in a body of water. It is used for a description of the terrain

relief below the surface of the water.


OGF_ID NUMBER(13) Yes OGF_ID A unique numeric provincial identifier assigned to each object.

DEPTH NUMBER(6,1) Yes DEPTH The extent downward from the surface measured in metres (m).

SURVEY_METHOD VARCHAR2(8) No SURV_METH

The method used to collect the bathymetry information.VALID VALUES:

GPS

Transect

Other

SURVEY_DATE DATE No SURV_DATE The date when the survey was conducted.

CREATION_METHODOLOGY VARCHAR2(25) No METHODOL

The method used to generate the lines representing depth. For example, the bathymetry lines may be taken from an original paper map or may be derived by a GIS.VALID VALUES:

Hand Digitized

GIS Derived

Other

LOCATION_ACCURACY VARCHAR2(25) Yes ACCURACY

The degree of conformity or closeness of a measurement within the database to its true value in the world.Valid Values: See LOCATION_ACCURACY_LIST lookup table in appendix.

15


GEOMETRY_UPDATE_DATETIME DATE No GEO_UPT_D

TDate/time the geometry was created or last modified in the source database.

EFFECTIVE_DATETIME DATE Yes EFF_DATE Date/time the record was created or last modified in the source database.


SHAPE SDO_GEOMETRY No SHAPE Geometry attribute.

6.3 BATHYMETRY_POINT_FT

Points indicating the measurement of water depth at various places in a body of water.


OGF_ID NUMBER(13) Yes OGF_ID A unique numeric provincial identifier assigned to each object.

DEPTH NUMBER(6,1) Yes DEPTH The extent downward from the surface measured in metres (m).

SURVEY_METHOD VARCHAR2(8) No SURV_METH

The method used to collect the bathymetry information.VALID VALUES:

GPS

Transect

Other

16


DIFF_CORRECTION_METHOD VARCHAR2(15) Yes DIFF_CORR

The Differential Correction Method applied to the GPS location. Potential options include: WAAS (Wide Area Augmentation System), CDGPS (Canada-Wide Differential Global Positioning System), Post Processed, Not CorrectedVALID VALUES:

CDGPS

WAAS

Post Processed

Not Corrected

DATA_COLLECTOR VARCHAR2(50) Yes COLLECTOR

The organization which collected the data.Valid Values:

MNR District

CA

FAU

COLLECTION_DATE DATE Yes COLL_DATE The date on which the data was collected.

BENCHMARK_WATER_LEVEL NUMBER(6,1) No BENCH_LEV The level of water recorded at the local benchmark measured in metres (m).

BENCHMARK_DESCR VARCHAR2(30) No BENCHMARK A description of the location of a local benchmark.


The degree of conformity or closeness of a measurement within the database to its true value in the world.Valid Values: See LOCATION_ACCURACY_LIST lookup table in appendix.

GEOMETRY_UPDATE_DATETIME DATE No GEO_UPT_D

TDate/time the geometry was created or last modified in the source database.

17


EFFECTIVE_DATETIME DATE Yes EFF_DATE Date/time the record was created or last modified in the source database.


SHAPE SDO_GEOMETRY No SHAPE Geometry attribute.

18

7. Links to Additional Information

Official Ontario GeoHub Metadata Record for Historic Bathymetry Maps

(https://geohub.lio.gov.on.ca/datasets/99a8bfcd83b34e079094c0c880080178)

Official Ontario GeoHub Metadata Record for Bathymetry Index

(https://geohub.lio.gov.on.ca/datasets/394f1db0753f40228cc70acf0036707f_31)

Official Ontario GeoHub Metadata Record for Bathymetry Line

(

https://geohub.lio.gov.on.ca/datasets/944bc611791343d985880207d799a0e6_30

)

Official Ontario GeoHub Metadata Record for Bathymetry Point

(https://geohub.lio.gov.on.ca/datasets/62ceff6eff3b4bf39c462f2d610fe3ff_27)

MNRF’s Fish ON-Line web mapping (includes lake contours from Bathymetry

Line where available) (https://www.ontario.ca/page/how-use-fish-line)

19

https://www.ontario.ca/page/how-use-fish-line

https://geohub.lio.gov.on.ca/datasets/62ceff6eff3b4bf39c462f2d610fe3ff_27

https://geohub.lio.gov.on.ca/datasets/944bc611791343d985880207d799a0e6_30

https://geohub.lio.gov.on.ca/datasets/394f1db0753f40228cc70acf0036707f_31

https://geohub.lio.gov.on.ca/datasets/99a8bfcd83b34e079094c0c880080178

APPENDIX A: LIO Lookup Tables and Values

LOCATION_ACCURACY_LIST

List of valid location accuracies.



The accuracy of the location of the feature at an OBM scale. The degree of conformity or closeness of a measurement to the true value.

EFFECTIVE_DATETIME DATE Yes EFF_DATEDate/time the record was created or last modified in the source database.Default: SYSDATE

EXPIRY_DATETIME DATE No EXP_DATE Date/time that the record was expired from use.

LOCATION_ACCURACY_LIST Permissible Values

LOCATION_ACCURACY EXPIRY DATETIME

Not Applicable Not applicable

Over 10,000 metres Not applicable

Within 1 metre Not applicable

Within 10 metres Not applicable

Within 10,000 metres Not applicable





20

LOCATION_ACCURACY EXPIRY DATETIME







AC Accurate (to 10m) 2007-01-12

AP Approximate (to 500m) 2007-01-12

GE General (to 10,000m) 2007-01-12

MO Moderate (to 1000m) 2007-01-12

RE Reliable (to 100m) 2007-01-12

VA Very Accurate (to 2m) 2007-01-12

VG Vague (to 100,000m) 2007-01-12

^ Data Load 2007-01-12

21

APPENDIX B: Table Key Dependency and Relationship Index

Keys are used to link or make relationships between tables through one or more columns. A Parent

Table is the source of unique key columns used by a Child Table. The main key types are described

below.

Primary Key (PK):

A Primary Key (PK) is a column that uniquely identifies each record in a table. There can be more

than one PK defined for a table when additional rules for record uniqueness are needed. Primary

Keys cannot contain null values.

Figure 1: Primary Key example

Foreign Key (FK):

When a Primary Key from a Parent Table appears as a column in the Child Table it is referred to as a

Foreign Key (FK). The FK may retain the same name of the Parent Table column, or it may be

renamed.

Figure 2: Foreign Key example

Alternate Key (AK):

Alternate Keys (AK) are secondary unique identifiers in a Parent Table. A Child Table can link to a

Parent Table AK and use it as a Foreign Key (FK). The FK may retain the same name of the Parent

Table column, or it may be renamed. Alternate Keys allow null values.

Figure 3: Alternate Key example

22

There are two relationship type options, identifying and non-identifying, which are described below.

An Identifying Relationship occurs when a column from the Parent Table is added to the key

section of the Child Table. Though technically a Foreign Key (FK) in the child table, it now forms part

of the Primary Key (PK). Identifying Relationships are symbolized with a solid line.

Figure 4: Example of an Identifying Relationship

A Non-identifying Relationship occurs when a column from the Parent Table is added to the main

body of the Child Table where it is treated as a Foreign Key (FK). Non-identifying Relationships are

symbolized with a dashed line.

Figure 5: Example of a Non-identifying Relationship

The relationships between tables are set up with cardinality rules describing if the feature record in

the Parent Table can relate to zero, one or more records in the associated Child Table and vice

versa. These rules are symbolized in the model diagram as follows.

Figure 6: Model Diagram Relationship Symbology Table

The following section is an index of parent table primary keys identifying, where applicable,

associated child table dependencies that have been implemented for the Bathymetry data classes

23

Lookup Table Indexes

Where a lookup table primary key (PK) is used as a foreign key (FK) in other main business area

tables in order to control permissible values.

Note: Relationship type reference is either Identifying (I) or Non-Identifying (NI).

Parent Table: LOCATION_ACCURACY_LISTPrimary Key(s): LOCATION_ACCURACYData Type: VARCHAR2 (25)

Child Table Migrated Foreign Key Rel. Type

Parent to Child Relationship

Child to Parent

Relationship

BATHYMETRY_LINE_FT LOCATION_ACCURACY NI Optional: 1 to

manyMandatory:1 to 1

BATHYMETRY_POINT_FT LOCATION_ACCURACY NI Optional: 1 to

manyMandatory:1 to 1

24

Version 1617.1

25

Date post:	16-Jul-2021
Category:	Documents
Upload:	others
View:	1 times
Download:	0 times

Bathymetry User Guide · Web viewProvincial Mapping Unit Mapping and Information Resources Branch...

Documents