Swan Coast hydrologically enforced digital elevation model (HDEM) 2008  

Authors / CoAuthors

Abstract

The Swan Coast hydrologically enforced digital elevation model (HDEM) was produced in 2010 as part of the Urban DEM project managed by the CRC for Spatial Information and Geoscience Australia. The HDEM was created from a combination of the following surveys; Perth, Peel, Harvey, Bunbury and Busselton LiDAR The Swan Coast 2008 LiDAR data was captured over the Swan Coast region during February, 2008. The data was acquired by AAMHatch (now AAMGroup) and Fugro Spatial Solutions through a number of separate missions as part of the larger Swan Coast LiDAR Survey that covers the regions of Perth, Peel, Harvey, Bunbury and Busselton. The project was funded by Department of Water, WA for the purposes of coastal inundation modelling and a range of local and regional planning. The data are made available under licence for use by Commonwealth, State and Local Government. The HDEM was produced by SKM using the ANUDEM program. The HDEM ensures that primary stream/channel flow, and water flow across the land surface are accurately represented. The hydrologically enforced HDEM depicts water bodies as being flat, and water courses depict consistent downward flow of water unimpeded by vegetation or man-made structures such as bridges and major culverts. Drainage enforcement was limited to watercourse lines depicted on 1:25,000 topographic mapping and to the intersection of the water course layer and transport layer. For the purposes of inundation modelling, inundation contours have been developed using the HDEM. The inundation extents were extracted at 0.2m intervals below 2m AHD and 1m intervals up to 10m. The inundation contours are available as polylines. The inundation contours have also been flagged as to whether the area connects directly to the sea. he data was captured with point density of 1 point per square metre and overall vertical accuracy has been confirmed at <15cm (68% confidence). The data are available as a number of products including mass point files (ASCII, LAS) and ESRI GRID files with 1m grid spacing.

Product Type

dataset

eCat Id

70833

Contact for the resource

Keywords

• DEM topographic

( Theme )

• DEM

( Theme )

• digital elevation data

( Theme )

• marine

• AU-WA

Australian and New Zealand Standard Research Classification (ANZSRC)

• Topology

• Published_Internal

Publication Date

2008-01-01T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Special, MOU, etc.

Access - restricted

Use - license

Status

Purpose

Maintenance Information

unknown

Topic Category

elevation

Series Information

Lineage

The data were acquired with fixed wing aircraft. GPS base station support was provided the the Perth GPS Network. Reduction of the LiDAR data to the Australian Height Datum proceeded without any significant problems. The aim of the HDEM processing was to ensure that primary stream/channel flow, and water flow across the land surface are accurately represented in the gridded data. For the purposes of inundation modelling inundation contours were also developed using the HDEM. The inundation extents were extracted at 0.2m intervals below 2m AHD and 1m intervals up to 10m. The inundation contours are available as polylines. The hydrologically enforced HDEM aims to depict water bodies as being flat, and water courses with downward flow of water unimpeded by vegetation or man-made structures such as bridges and major culverts. 1:25,000 scale water course and transport mapping was used as reference material and to assist with processing. In most cases, bridges and culverts were removed from the 'bare earth' dataset, and breaklines inserted in shorelines and an assumed water course centreline. It was impractical to expect forced breaklines through terrain to be placed exactly over culvert locations. However, the breaklines were placed in the vicinity of the culvert locations to ensure that the hydrological model accounts for the impact of flows from the culverts. DEM production methodology utilised a hybrid approach of applying TIN and ANUDEM based processes to ensure that hydrological stream enforcement was achieved whilst maintaining a metrically accurate DEM. NEDF Metadata Acquisition Start Date: Monday, 25 February 2008 Acquisition End Date: Monday, 25 February 2008 Sensor: LiDAR Device Name: Leica ALS50-II (S/N: 091) Flying Height (AGL): 2170 INS/IMU Used: Unknown Number of Runs: UNK Number of Cross Runs: UNK Swath Width: UNK Flight Direction: UNK Swath (side) Overlap: UNK Horizontal Datum: GDA94 Vertical Datum: AHD71 - using local Geoid model Map Projection: MGA50 Description of Aerotriangulation Process Used: - Description of Rectification Process Used: - Spatial Accuracy Horizontal: UNK Spatial Accuracy Vertical: 0.15 Average Point Spacing (per/sqm): 1 Laser Return Types: 4 pulses (1st 2nd 3rd 4th and intensity) Data Thinning: - Laser Footprint Size: 0 Calibration certification (Manufacturer/Cert. Company): Fugro Spatial Solutions Pty Ltd Limitations of the Data: Incomplete metadata supplied Surface Type: HDEM Product Type: GRID Classification Type: C2 Grid Resolution: 2 Distribution Format: ESRI GRID Processing/Derivation Lineage: Fugro Spatial Solutions Pty Ltd WMS: http://nedf.ga.gov.au:8399/arcgis/services/SwanCoast_2008_HDEM/MapServer/WMSServer?

Parent Information

Extents

[-32.928101, -31.837193, 115.606522, 116.04865]

Reference System

Spatial Resolution

Service Information

Associations

Downloads and Links

Source Information

Swan Coast HDEM 2008