While Theo's & LBuck's suggestions are sound, I suggest you plan an outdoor wedding at your pond. Sure enough, you'll get some rain.
Granted you might have $10,000 to $20,000 in sunk costs for the caterer, band, minister, etc., but isn't it worth it?
Excerpt from Robert Crais' "The Monkey's Raincoat:" "She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."