Question:
Sure water and power can be run that far. You may want to increase the wire
size and install a weather proof circuit panel out there. It might be wise
to have an electrician run the wiring thru conduit and install outlets or
lights as you desire. Do this before you pour the concrete slab.
As for drainage, just let it water the trees. As long as the chemicals have
dissapated in the water this shouldn't harm any plants.
Enjoy the hot tub, we love our HotSpring. (ours is inside, but a gazebo
sounds great).
Answer:
I agree on the water and power issues. Be sure you look at NEC article
680 for the proper grounding and use GFCI protected circuits for the
tub and any receptacles (which must be 5 feet or more from the tub).
As for the "chemicals" and your trees. If the tub is "right" it will
very closely approximate city water. When I lived in DC my city water
tested perfect on my spa test kit so I don't see any problem with
dumping spa water into the garden or on the grass if you water with a
hose normally. I have been using my washing machine water to water a
mango tree for years here in Fla and that is my healthiest area of
the yard.
