[GRASS-dev] Linking vector to raster

[David Townshend]

Hi

I am working on a urban stormwater pollution model which I intend to
base on r.sim.water and r.sim.sediment. Part of the requirements of
this model is that is should accommodate pipe flow. It seems that the
best way of implementing this is to modify r.sim.water to route flow
though a vector pipe network, using simple flow equations. The way it
would work is that as r.sim.water calculates the flow across the
surface, when it reaches a cell which contains a pipe inlet, it
diverts a certain amount of water to the pipe (removing it from the
surface flow). Similarly, at the network outlet, the flow from the
pipe is added to the suface flow of the cell in which the outlet
occurs. Where I am struggling slightly is figuring out how to create
the relationship between the surface (raster) and the pipes (vector).
So far the best option I have thought of is to generate a second
raster with values at the inlet and outlet cells linking to the pipe
reference.

Can anyone comment on this, or suggest a better way of doing it?

David