Event Title
Description
Geographic Information Systems (GIS) typically rely on raster grid data structures to define surface hydrography and define watershed boundaries. The interpolation of grids from sample points and the algorithms used to define flow directions introduce error and compromise data quality, especially in areas of low relief. This research proposes a new approach in hydrographic geomorphometry, using Voronoi diagrams generated from airborne laser altimetry data points to determine flow direction and define watershed boundaries for the Lummi Indian Reservation in Whatcom County, Washington State. In theory, the Voronoi diagram approach will bypass the errors introduced by the raster grid by constructing a connected network expressing flow direction generated directly from sample point data. The Voronoi surface output will be compared with the raster grid output and measured for accuracy based on a field survey of selected water courses.
Document Type
Event
Start Date
8-3-2008 8:00 AM
Subject - LCSH
Watershed hydrology--Washington (State)--Lummi Tribe of the Lummi Reservation; Optical radar--Washington (State)--Lummi Tribe of the Lummi Reservation
End Date
8-3-2008 5:00 PM
Session
GIS and Spatial Data
Genre/Form
conference proceedings
Type
event
Geographic Coverage
Lummi Tribe of the Lummi Reservation, Washington
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.
Language
English
Format
application/pdf
Keywords
Geographic Information Systems, LIDAR, watershed, data structure, hydrography, geomorphometry, Voronoi
Included in
Voronoi diagram approach to defining surface hydrography using LIDAR-generated bare earth sample points.
Geographic Information Systems (GIS) typically rely on raster grid data structures to define surface hydrography and define watershed boundaries. The interpolation of grids from sample points and the algorithms used to define flow directions introduce error and compromise data quality, especially in areas of low relief. This research proposes a new approach in hydrographic geomorphometry, using Voronoi diagrams generated from airborne laser altimetry data points to determine flow direction and define watershed boundaries for the Lummi Indian Reservation in Whatcom County, Washington State. In theory, the Voronoi diagram approach will bypass the errors introduced by the raster grid by constructing a connected network expressing flow direction generated directly from sample point data. The Voronoi surface output will be compared with the raster grid output and measured for accuracy based on a field survey of selected water courses.