Aqua Adventure Waterpark in Fremont is open daily from 11 to 4, with occasional special events that keep the park open later, until the end of August at which time it is only open on the weekends. Check the schedule here.
It's not an overwhelmingly large water park, and for most kids over six, you could probably plant yourself somewhere and they can navigate by themselves a bit.
There are tables with shade over them, but they may be full. Bring lawn chairs, towels, and an umbrella to create shade for yourself. We brought our Sportbrella which was perfect for this setting.
There is one set of big slides that you have to be 48 inches to ride. Those under 48 inches will spend their time in the Roundabout River, the climbing structure, and the little kids area. The River can be enjoyed without a tube, or with a tube which you rent for $3.
For my daughter who was a daring and strong swimmer, but under 48 inches, this water park was a little frustrating. If she was a bit younger, she wouldn't have cared because she would have enjoyed the little kids area more. We'll definitely go back when she's 48 inches, because the admission cost is much less than a traditional large water park like Waterworld in Concord.
Outside food is not allowed inside the park, as they have a restaurant, “The Grill”, but a picnic area is available in the parking lot if you wish to tailgate. Plus, there is an Indian catering menu from which you can order and have delivered, including extensive Indian vegetarian options. (I love the East Bay!)
Prices are hard to nail down because there seem to be so many specials available, but it's about $19 per non-resident person over 4 feet tall, $14 per person under 4 feet tall and over 3 years old. Admission for toddlers 3 and under is $2.00 and includes a swim diaper.
A lap swimming pool offers parents the opportunity to take turns getting some exercise.
Where is it? Aqua Adventure is at 40500 Paseo Padre Parkway in Fremont, about 30 miles south of Oakland's Lake Merritt.