One kind of spatial data is still not in the national databases, and this is bathymetric data from lakes. This paper
describes the data standards associated, the methods of surveying including historic. It describes the history of
Danish lake mapping, and produces an inventory over surveyed Danish lakes. It discusses how to choose standards
for lake mapping. The paper suggests that crowd sourcing might be applied to collect data, and discuss the
various aspects in crowd sourcing VGI. Vertical accuracy in consumer echo sounders is tested. Parsing data from
echo sounders are demonstrated. Finally a Web-Gis is constructing visualizing Danish lake maps and VGI data,
presenting a upload functionality and addressing issues with metadata necessary for further post processing of
data.