I took a scouting trip today to the Emeryville Crescent. Kafka and I searched for the old entrance but there is a fence where it used to be. You can still see the marsh close enough if you park on Powell across from the Watergate Towers sign, but the grass is way higher than it was in April. If you are like me and want to avoid ticks, this is not the ideal situation. So I propose we meet at the very end of Powell, in front of the Hong Kong East Ocean Seafood restaurant. There is ample parking on Marina Park, and we can walk to the water very easily from there.
From 80, take the Powell exit west. If you are coming from Berkeley or El Sobrante, turn left at the second light and follow Powell all the way to the end, where there is a marina and a huge parking lot.