There's a dog beach but I doubt that's what you were thinking! If you drive down past the dog park and park in the lot on the right and walk through the trail there, there are areas with some water, but you are in the woods and it's not really beachy. There are also some trails that lead to the park on your right as you enter, but again, not beachy. The dog beach area has changed a lot since I used to go there a few years ago, but there used to be a barrier and beyond that a sandy area that the dogs didn't use. The last time I went to the dog beach, though, it didn't look like it would be possible to get over there. You could go scope it out in advance.
Mama to DS1 (2/08) and DS2 (9/10).