On Wed, 5 Oct 2016, Thomas Adams wrote:
You understand, don't you, that the point you are using to define your 'dam', delineates a watershed;
Tom, Yes, I do understand.
You also need to generate a storage-elevation curve, which will relate the water level (which r.lake needs) to the volume behind your dam (assuming none escapes, otherwise the problem gets more complicated) -- the change in volume depends on the inflow rate, which a hydrologic model will provide.
This is flat, agricultural land with no defined streams. The only inflow comes from precipitation; what does not infiltrate into the soil and drains to the swale adjacent to the county road, along with surface runoff, flows through a culvert (the 'dam.')
Typically, hydrologic models are calibrated against observed flow data. There is the further assumption that the inflow spreads over the lake surface instantaneously, which for a small surface area is not altogether unreasonable...
My reading of the manual pages for r.sim.water and Itzi suggest they, too, require perennial streams in defined channels. There should be a set of modules that work for my need here. If you have suggestions please share them with me. Thanks, Rich _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
