From Highway 80, take the Carlson Blvd. exit west towards the water, and go left (over 580) on Bayview Ave. It will curve dramatically. You will immediately see a freeway exit to 580 on your right. Stop there and right across the street on your left is Seaport Ave. Turn left on Seaport, and turn left on S 51 St. Park at the end of this dead end street, get through entrance and you will see a bridge. We will meet there. It is not possible to take 580 and get off on Bayview Ave. Another way to get there is to park at Point Isabel and walk 15 minutes to the bridge adjacent S 51 St. Bring a chair, it may be wet at your preferred painting location.
The Hoffman marsh may not look like much, but it has a very interesting political history, according to Wikipedia:
The marsh is the delta for the mouth of Fluvius Innominatus creek into the Hoffman Channel which leads to San Francisco Bay. The marsh has been proposed to be included in the Eastshore State Park as it is one of only a handful of undestroyed wetlands in the Bay Area. The marsh is an important nesting ground for wildfowl and stopping ground for the Pacific Flyway.
There is currently a controversial proposal to add a 98,000 sq. ft. (9,100 m²) Kohl's department store on a site between the Costco Store and the marsh. Many residents are worried about potential negative effects on increased nighttime lighting that will make endangered birds such as the California Clapper Rail and Salt Marsh Harvest Mouse more susceptible to predators. This is in addition to other birds that make overnight stopovers at the marsh that would also possibly decrease in number and therefore reduce biodiversity. The Richmond Annex Neighborhood Council has officially opposed the project.