Thanks for all the kind words, you guys. Can't tell you all how much I appreciate the positive feedback.
Armour_freek, the snow was made using a Woodland Scenics product called Snow :) First, a mix of Snow and diluted white glue was applied with a brush. Later, after the figures and vehicles were in place, a fine drift of the same product was sprinkled over the entire dio, brushed away from the running water, then "frozen" in place with Scenic Cement (also from Woodland Scenics). Should be able to find both those items anywhere scenery products are sold.