As per the title, I am looking for a tool that can produce bathymetry of a river from cross sections. Although people who may know such tools probably will not need any explanation why this kind of interpolation is a bit complicated, here are a few words of explanation for those which may know and use such things for other purposes.
In order to receive a DEM of river valley with river bed bathymetry, I need to fence/mark with barriers the area on my original DEM where bathymetry is to be created. Basically it is the whole area of the wet river bed where TLS did not have a chance to measure the bottom surface (bathymetry). Rivers are in various shapes, sometimes more meandering, sometimes more straight, and also the depth of the bottom and its alignment are varying a lot, which makes interpolation more complex as it has to follow the centre line of the river and also conduct the interpolation vertically and horizontally.
Dr Venkatesh Marwade has prepared such extension to ArcGIS 9.2, though I did experience some problems and was just wondering if anyone would know a piece of software or code that could generate something alike.
(Edit: see graphics in this tutorial.)