I would suggest NOT taking him to the Bothell pool. We took our toddler there for the parent/baby classes, and they were a complete waste of money. The "instructor" was a teenager who just stood in the water and did nothing. After I complained, the manager called me and then gave my name to another person who was supposed to give our money back. That never happened.
Anyway, if you can go the extra distance, I found the Mountlake Terrace Pool to be a wonderful place to take children! They are organized, fun, not too expensive, and the pool is great for kids of all ages. It has fountains, slides, toys, etc. to keep them all busy! Here is their website: http://www.ci.mountlake-terrace.wa.us/cityServices/recrea....
Good luck to you!