Swimmin’ in the Delta for Memorial Day

So here's the plan. We're all going to head up to Brannan Island on Monday and spend the day picnicking, BBQing, swimming in the delta, making sand castles, and squishing our toes in algae. So far a good number of people are in, this is just so everyone knows the plan. We'll get there around 11 in the morning and leave whenever we feel done.
First, if you're still on the fence, here's some information about the place. I went here as a kid all the time and it rules. You can check out the State Park page here. You can also look at the park brochure here (pdf).
This should be the poor man's memorial day also, since the cost will be gas, bridge toll, and 3-5$ for all day parking at the park.
So here are the logistics. You can come either in our caravan (save on parking/gas/bridge toll, and have fun people to talk to on the ride), or you can meet us at the site. I'll give directions for my my parents house where we will be staging, and directions to Brannan Island if you miss us or want to go on your own.
My parents live in Walnut Creek and we can meet and leave from there since it's easy to get to and close to the freeway. We will be departing from Walnut Creek at exactly 10:30AM. What this means is that you should arrive well before 10:30, since arriving at 10:31 means you get to drive on your own. My parents address is 792 Silver Oaks Place, Walnut Creek, CA. The easiest way to get there from SF, Berkeley/Oakland, etc. is the following.
* Take 24 Eastbound towards Walnut Creek.
* Merge onto Interstate 680 Northbound.
* Take your first exit, once on 680, which will be North Main St.
* The exit will loop around bringing you to a light. Turn right at the light onto North Main (Northbound).
* Continue on North Main until you come to the second light, which will be Second Ave. Turn left onto Second Ave.
* Continue on Second Ave. for about 2 blocks until you come to Silver Oaks Place.
* Turn left onto Silver Oaks Place, and it's the first house on the left. It's on the corner of Second Ave. and Silver Oaks Place.
If you can't make it by 10:30AM, or want to go on your own, here are directions to Brannan Island.
* Take 24 Eastbound towards Walnut Creek.
* Merge onto 680 Northbound.
* Take 680 North to the Junction with 242. 242 will be the righthand 2 or 3 lanes, and 680 will continue north in the lefthand 2 or 3 or lanes.
* Continue North on 242 and merge onto 4 Eastbound.
* Take 4 past Antioch and merge onto 160 Northbound which will take you over the Carquinez Strait.
* Continue on 160 until just after the Three Mile Bridge (not actually 3 miles long) where you will come to the entrance to the State Recreation Area AKA Park Entrance. Pay your parking, and drive into the park.
* Follow the main road into the park all the way to the "Beach-Swimming Area". There should be signs. There is a parking lot at the beach. Park and we should be down on on the beach.
I will bring a BBQ and coals. Bring your own food and there will probably be some stuff that people are sharing (potato salad etc.). Bring river shoes if you don't like walking in algae while swimming. Bring sand castle tools if that's your thing too.