Hi David,
Welcome to the Disney Parks Moms Panel! We're so happy you stopped by with your question today!
My family loves the water parks and we try to visit either Disney's Blizzard Beach Water Park or Disney's Typhoon Lagoon Water Park each time we're vacationing at Walt Disney World. Having a reserved spot in the shade for some rest and relaxation is definitely a treat, especially when you have little ones with you, and you actually have a couple different options available to you at Blizzard Beach. The first are "Polar Patios", which is a shaded area with cushioned seating, a personal locker, refillable drink mugs, towels, a Cast Member on hand to assist you during the day and a cooler just for you that's stocked with bottled water and ice. The current price for a full day is about $345 for up to 6 people (you can add additional people for $25 per person, up to a total of 10 people). A "Lodge Picnic Umbrella" is another nice option at Blizzard Beach. This offers a reserved spot in the shade under an umbrella with 4 chairs (2 sit-up style and 2 reclining style), a small table and 4 towels, and the current pricing for that is about $55.
You can make reservations for either of these up to 180 days in advance by calling the Recreation line at (407) WDW-PLAY (939-7529). Same-day rentals may also be available at the water park, depending on availability, but they can get snatched up quickly during the busier summer months.
I hope your vacation goes swimmingly, David! Please stop by again soon if we can help answer any other questions as you finalize your plans.
Beth