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titleCapture Process:

 

CANAL LINE

 

Definition: A constructed watercourse feature part of a residential, subdivision development used for recreational activities and marine navigation.

 

Alternate Terms: Canal, Waterway

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  •  Locations can be obtained from other datasets, existing mapping, address details, tourist publications, organisations, Local Government websites or other source material.

  • Capture down the centre of the feature for features less than 25 metres in width.

  • Capture in the direction of flow to maintain the linear drainage network.

  • For features greater than 25 metres in width, capture as a Waterbody Area with a Feature Type “Watercourse Area” and a Function of “Canal Estate”.

 

 

CONNECTOR

(see function “linear connector”)  

 

Definition: An artificial line placed to connect watercourse lines on either side of the waterbody area enabling drainage network analysis.

 

Alternate Terms:

 

  • Capture as a 2D polyline as function “linear connector”

  • Location is plotted from orthorectified imagery.

  • Capture in the direction of flow to maintain the linear drainage network.

  • Capture the best interpretation of where the feature could be located or as a straight line joining the visible ends of the watercourse features.

  • Where a watercourse flows through a swamp is not visible, a Feature Type “Connector” is used to join through the swamp.

 Not Connectors:

  • Where a watercourse channel flows through an Ephemeral “Watercourse Area” Feature Type and is clearly visible in imagery, a Feature Type “Watercourse” is used to continue the drainage network.

  • Where a watercourse flows through a “Subject to Inundation” Feature Type, a Feature Type “Watercourse” is used to continue the drainage network.

  • Where the channel of the watercourse is clearly visible in imagery through the swamp, a Feature Type “Watercourse” is used to continue the drainage network.

 

 

CULVERT

 

Definition: A structure (clearly visible in imagery), usually under a major road, railway, or major development to provide for the flow of water.

 

Alternate Terms: Box culvert

 

 

 

  • Capture as a 2D polyline

  •  Location is plotted from orthorectified imagery.

  •  Capture in the direction of flow to maintain the linear drainage network.

  •  Capture down the centre of the feature or the best interpretation of where original watercourse would be.

  • Culverts are generally only shown under railways and roads classified as motorway, highway, main road or secondary road or major developments’ unless the culvert is significant in the environment.

  • The culvert must be of a large structure, clearly visible in imagery or the embankments of the culvert be at least 10 metres high. Where the above conditions are not met, or a bridge, floodway, ford, or causeway exists, no culvert is shown, and the adjoining feature type (generally a watercourse) is concatenated to form a single line string in the direction of flow under the road or railway.

  • The culvert should be roughly at a right angle to the road/railway unless clearly shown otherwise.

  • If the feature is less than 25 metres in length, exaggerate to a minimum length of 30 metres.

  • The linear watercourse features on either side of the culvert are snapped to the ends of the culvert to create a continuous linear network in the direction of flow.

 

 

DEM CONNECTOR

(see function “linear connector”)  

 

Definition: An artificial line placed when the watercourse feature disappears beneath the landscape or land development.

 

Alternate Terms:

 

 

 

  • Capture as a 2D polyline as function “linear connector”

  • Location is plotted from orthorectified imagery.

  • The underground location is difficult to determine.

  •  Capture in the direction of flow to maintain the linear drainage network.

  • Capture where the feature could be located or as a straight line joining the visible ends of the watercourse features.

  • DEM Connectors will carry the attributes of the watercourse they represent.

  • An artificial line used to connect linear hydrographic features across dry land (e.g., no defined waterbody area or mangrove) to allow network analysis of riverine networks. DEM Connectors join related hydrological features where no visual evidence via imagery interpretation is achievable (e.g., minute changes in elevation or water flows into a soak hole and hydrological features are then connected via groundwater). DEM Connectors can be used to enforce Digital Elevation Models.

 

 

DRAIN

 

Definition: A narrow constructed watercourse designed for the purpose of removing surplus water from the lands surface.

 

 

 

 

Alternate Terms: Ditch, Drain, Bore Drain

 

 

 

 

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  • Capture in the direction of flow to maintain the linear drainage network.

  • Capture down the centre of the feature for features less than 25 metres in width and greater than 150 metres in length.

  • For features greater than 25 metres in width, capture as a Waterbody Area with a Feature Type “Watercourse Area” and a Function of “Drainage Channel”

       NOTE: A drain may be captured as part of the continuous linear drainage network, providing continuation of flow for a named or unnamed watercourse.

 

 

IRRIGATION LINE

 

Definition: A constructed watercourse usually part of a network for irrigation, used when directing water from one source to another.

 

Alternate Terms: Aqueduct, Channel

 

 

 

 

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  •  Locations can be obtained from other datasets, existing mapping, address details, organisations, Local Government websites or other source material.

  • Capture in the direction of flow to maintain the linear drainage network.

  • Capture down the centre of the feature for features less than 25 metres in width and greater than 150 metres in length.

  • For features greater than 25 metres in width capture as a Waterbody Area with a Feature Type “Watercourse Area” and a Function of “Irrigation Channel”.

  • NOTE: If an irrigation line is a pipeline, it may be captured as either Underground Connector, or if above ground, a Connector, not a Watercourse – constructed.

 

 

LINEAR CONNECTION

 

 

Definition: An artificial line joining between watercourse lines to create a continuous linear network for analysis.

 

Alternate Terms:

 

 

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  • Capture in the direction of flow to maintain the linear drainage network.

  • This function is used for Feature Types “Connector, DEM Connector, Underground Connector.” 

 

NATURAL WATERCOURSE  

 

Definition: A natural channel that may or may not contain water on a permanent basis but may flow intermittently or seasonally.

 

Alternate Terms: Anabranch, Branch, Brook, Burn, Creek, Gully, River, Stream, Tributary

 

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  • Locations can be obtained from other datasets, existing mapping, tourist publications, organisations, Local Government websites or other source material.

  • Capture in the direction of flow to maintain the linear drainage network.

  • Capture down the centre of the feature for features less than 25 metres in width.

  • For features greater than 25 metres in width capture as a Waterbody Area with a Feature Type “Watercourse Area”

  • For features in open terrain, capture features greater than 750 metres in length.

  • For features in steep terrain, capture features greater than 500 metres in length

  • See also “Connector” for when a watercourse replaces a connector through waterbodies.

  • Where a watercourse flows through a non-perennial “Watercourse Area” Feature Type and is clearly visible in imagery, a Feature Type “Watercourse” is used to continue the drainage network.

  •  Where a watercourse flows through a “Subject to Inundation” Feature Type, a Feature Type “Watercourse” is used to continue the drainage network.

  • Where the course of the watercourse is clearly visible in imagery through the swamp, a Feature Type “Watercourse” is used to continue the drainage network.

 

 

RAPIDS LINE 

 

Definition: A place of broken fast flowing water in a watercourse, caused by the narrowing of the banks or a change in gradient of the watercourse bed.

 

 

Alternate Terms: Cascades, Chut, White Water

 

 

 

 

  • Capture as a 2D polyline

  •  Location is plotted from orthorectified imagery.

  • Locations can be obtained from other datasets, existing mapping, tourist publications, organisations, Local Government websites or other source material.

  • Capture in the direction of flow to maintain the linear drainage network.

  • Capture down the centre of the feature for features less than 25 metres in width and show a minimum length of 50 metres.

  • For features greater than 25 metres in width capture as a Waterbody Area with a Feature Type “Watercourse Area” and a Function of “Rapids Area”

 

 

SPILLWAY LINE  

 

Definition: A constructed path or channel allowing excess water to pass over or beside the waterbody.

 

Alternate Terms: Duct

 

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  • Locations can be obtained from other datasets, existing mapping, tourist publications, organisations, Local Government websites or other source material.

  • Capture in the direction of flow to maintain the linear drainage network.

  • Capture down the centre of the feature, if required extend the features length to a minimum of 25 metres

  • For features greater than 25 metres in width capture as a Waterbody Area with a Feature Type “Watercourse Area” and a Function of “Spillway Area”

 

 

UNDERGROUND CONNECTOR

(see function “linear connector”)  

 

Definition: An artificial line used to connect water features underground, where the path is generally known but not visible. Connection could be through pipes or natural seepage.

 

Alternate Terms: Underground pipes

 

 

  • Capture as a 2D polyline as function “linear connector”

  • Location is plotted from orthorectified imagery.

  • The underground location is difficult to determine.

  • Capture in the direction of flow the best interpretation of where the feature could be located or as a straight line joining the visible ends of the watercourse features.

  • If the end point of the connector cannot be determined, an assumption is not made as to where the watercourse may flow, and a connector will not be captured.

  • Do not capture where the Feature Type “Culvert” would be more appropriate to use.

 

WATER SUPPLY LINE

 

Definition: A constructed watercourse used to enable the transfer of stored or available water from one area to another.

 

Alternate Terms:

 

 

  • Capture as a 2D polyline

  • Location is plotted from orthorectified imagery.

  • Locations can be obtained from other datasets, existing mapping, address details, tourist publications, organisations, Local Government websites or other source material.

  • Capture down the centre of the feature for features less than 25 metres in width and show a minimum length of 150 metres.

  • For features greater than 25 metres in width, capture as a Waterbody Area with a Feature Type “Watercourse Area” and a Function of “Water Supply Channel”.

 

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