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.

Start Date

8-3-2008 8:00 AM

End Date

8-3-2008 5:00 PM

Subject - LCSH

Watershed hydrology--Washington (State)--Lummi Tribe of the Lummi Reservation; Optical radar--Washington (State)--Lummi Tribe of the Lummi Reservation

Geographic Coverage

Lummi Tribe of the Lummi Reservation, Washington

Genre/Form

Conference Papers and Proceedings

Session

GIS and Spatial Data

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.

Digital Format

application/pdf

Language

English

Type

event

Included in

Geography Commons

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Mar 8th, 8:00 AM Mar 8th, 5:00 PM

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.