Under the file menu in the Terrain Editor select the "Export Water To Bitmap" option.
Once this is done close the Terrain Editor.
In your terrains root folder you will now see a new folder called "imptexpt".
Open the file named "waterd.bmp" in that folder with Photoshop (warning it's a 16meg+ size file) and fill it with solid white.
Index value 255,255,255. Save the file as an indexed 8bit bitmap image. This will make it all land.
Next go back to your terrains root folder and open the "gndtype.bmp" file in Photoshop and fill it with index color 17,17,17 and save it as an indexed
8bit bitmap image.
This will paint it all "Grass".
Now go back and open the Terrain Editor again and load your terrain file. Then under the File menu select "Import Water" and once that is done
save your terrain and close the Terrain Editor and then start it back up and load your terrain again.
It should all be land with grass on it.
You can draw the water back in the places you might want it later.
Sorry I didn't reply earlier to your question...I was at work.
midi