I haven't looked, but it should be fairly easy to convert. Unless the data is in one of the proprietary GIS formats, then you're in for a late night hellride.

I haven't looked, but it should be fairly easy to convert. Unless the data is in one of the proprietary GIS formats, then you're in for a late night hellride. GDAL/OGR may be your friend, or may not. It looks like a nice dataset, but only has center lines for rivers -- no polygon data.