User Guide for Bathymetry LIO Data Classes Provincial Mapping Unit Mapping and Information Resources Branch Corporate Management and Information Division Ministry of Natural Resources and Forestry 2022-07-15
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
© 2019, Queen’s Printer for Ontario 2
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
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
Column Name Column Type Mandatory Short Name Description
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.
Column Name Column Type Mandatory Short Name Description
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
Column Name Column Type Mandatory Short Name Description
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.
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 Geometry attribute.
6.3 BATHYMETRY_POINT_FT
Points indicating the measurement of water depth at various places in a body of water.
Column Name Column Type Mandatory Short Name Description
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
Column Name Column Type Mandatory Short Name Description
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.
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.
GEOMETRY_UPDATE_DATETIME DATE No GEO_UPT_D
TDate/time the geometry was created or last modified in the source database.
17
Column Name Column Type Mandatory Short Name Description
EFFECTIVE_DATETIME DATE Yes EFF_DATE Date/time the record was created or last modified in the source 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 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
APPENDIX A: LIO Lookup Tables and Values
LOCATION_ACCURACY_LIST
List of valid location accuracies.
Column Name Column Type Mandatory Short Name Description
LOCATION_ACCURACY VARCHAR2(25) Yes ACCURACY
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
Within 100 metres Not applicable
Within 1000 metres Not applicable
Within 2 metres Not applicable
Within 20 metres Not applicable
20
LOCATION_ACCURACY EXPIRY DATETIME
Within 200 metres Not applicable
Within 2000 metres Not applicable
Within 5 metres Not applicable
Within 50 metres Not applicable
Within 500 metres Not applicable
Within 5000 metres Not applicable
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