Analysis of historical events can lead to speculating about the future. Throughout the 20th century, storms caused serious flooding in the Mill Valley area on several occasions. Today, frequent flooding of the Manzanita area is likely caused by the persistent rise in sea level. Scientists predict that by 2100, the sea level could be four feet higher than it is today. Hundreds of homes and businesses in the Mill Valley area could be inundated. Bay Front Park and Bothin Marsh would be submerged. A tidal barrier from Strawberry Point to the heliport could block high tides. Tidal Barrier 94941 could initially be built to block a one-foot sea level rise. Its height could then be increased periodically. Costs would be justified by preventing the abandonment of low-lying homes and businesses. The relatively affluent property owners in Mill Valley 94941 would probably be required to provide financing. Other such projects in less affluent Marin communities could have priority for accessing federal and state government grants. The Marin County Flood Control and Water Conservation District staff is currently studying the sea level rise issue. Mill Valley 94941 is in Flood Control Zone 3.