Sammendrag
Experiences with the use of bathymetric LiDAR
in modelling rivers. An accurate representation
of river bathymetry is important for many
applications in river engineering, flood assessment and environmental impact studies. Numerous methods are used to collect these data from
surveying by GPS and total stations to multibeam sonar scanning. Common for all methods
are that they do not easily cover all river reaches
and that is time consuming to cover long reaches
of river. Bathymeric LiDAR is a technology
where a green laser beam is applied from planes
and helicopter to scan the surface of the earth,
and unlike the more common topographic
LiDAR this instrument penetrates the water
surface and can thereby map the terrain under
water. This can provide an efficient way of collecting bathymetry data. In this paper we summarize the experiences of using bathymetric
LiDAR in several projects over the last five years.
We will look at data quality, the need for additional or correction data and the process of
utilizing the bathymetric LiDAR for hydraulic
analysis. We will illustrate the use of LiDAR
based bathymetry through examples from several hydraulic modelling project
in modelling rivers. An accurate representation
of river bathymetry is important for many
applications in river engineering, flood assessment and environmental impact studies. Numerous methods are used to collect these data from
surveying by GPS and total stations to multibeam sonar scanning. Common for all methods
are that they do not easily cover all river reaches
and that is time consuming to cover long reaches
of river. Bathymeric LiDAR is a technology
where a green laser beam is applied from planes
and helicopter to scan the surface of the earth,
and unlike the more common topographic
LiDAR this instrument penetrates the water
surface and can thereby map the terrain under
water. This can provide an efficient way of collecting bathymetry data. In this paper we summarize the experiences of using bathymetric
LiDAR in several projects over the last five years.
We will look at data quality, the need for additional or correction data and the process of
utilizing the bathymetric LiDAR for hydraulic
analysis. We will illustrate the use of LiDAR
based bathymetry through examples from several hydraulic modelling project