Creeks and waterways

[SAR704]

Just wondering. Is there a way to have splines exported through Transdem placed at a specific height below the terrain? Say 1-4 metres? There is a .kml that I've sourced for an arid part of the state that literally has thousands of crevices/creeks that are continuous. Just an aerial overlay via UTMs doesn't seem to cut it.

 

[sw1500]

I do not think so. How would something like that work? What part of the creek would the measurements be based on? Where along the water spline should the measurement be taken? If it is taken at the spline points compared to the bottom of the creek then you must make sure that the downstream point is lower than the upstream creek bottom.

If the measurement is taken at the spline points compared to the surrounding area, how would it look if the creek flows from a generally flat area into a rocky gorge? For a small shallow river how would the program tell where the riverbank is?

 

[TSwenson]

So you are trying to model a watercourse (stream/creek/brook/river) in an arid [desert] area, and are you trying to model where the watercourse's liquid disappears and reappears but the terrain it still indicative of a watercourse?
My interpretation of what you posted is that you have a Digital Elevation Map (DEM) of the area which you have used Transdem to create a route map in Trainz and are trying to model the fine watercourse features of a desert. Based on that, it seems like you want to be able to put in a spline under the terrain that can then be referenced to bulk update so that you aren't spending weeks modeling thousands of miles of streambed.
If I'm somewhat correct, I've no idea if it is even possible, and suspect that it isn't. It has been years since I messed with DEMs, but as I recall you get the TIGER data overlaid as a graphic/ground texture.

 

[JCitron]

I don't think this will work either due to how splines work. Splines by default will follow the terrain unless they are set to a fixed height. Setting a spline to a fixed height is fine for a known height such as a road that's going to be 15 meters above a valley for instance. This won't work with TransDem because there's no way of knowing what the height is going to be at the many locations that the watercourse traverses.

If the height is set to a fixed height and brought into TransDem, the end-user will spend hours, or probably days and then years, adjusting the watercourse splines to their proper height in the terrain. Years because they won't all be found the first time around and will rear up their nasty heads long after the route is finished.

 

[SAR704]

I don't intend to represent the entire of what's shown in the image. The terrain adapts naturally in regards to the end of the spline. It's not like there's a dark void where the waterway is at the bottom, terrain is 1.5 metres higher, with a black hole to who knows where in the middle. The image itself is dozens of kms wide. The route itself would only have a catchment of about 1.5 - 2.5kms at most.

It wouldn't be super tedious to lower each spline by 1.5 metres I guess in an individual section. But given the line which I have contemplated modeling dozens of times is about 350kms approximately, it would get tiring. I tend to model from one siding to another. Such sidings are about 10-30 miles apart in this route. Similar challenge as with Railworks and the randomly scattered saltbush with no consistency. I ended up ditching it a year after I started the section from Hookina to Mern Merna. Around 16.8 kms in length. These environments might lack buildings to a degree. But I'm sure it's no less demanding than an urban environment of 300kms or more in length.