On Jan. 3rd, low-lying areas of Marin County were hit with massive flooding from an unexpectedly high king tide.   Some say it is a preview of what will become common as sea levels rise. And the city of San Rafael isn’t waiting for it to become a reality to try and protect its most vulnerable neighborhood. … The first proposal, Alternative 1, is to raise all the edges of the creek, increasing the height of the banks and flood walls. … Alternative 2 is to raise the outer banks and add a gate at the end that can be closed when the tide gets too high. That would cost more, but with sea level rise projections, might only be effective until about the year 2050. Finally, Alternative 3 is a complete renovation of the Canal District shoreline, removing about 550 existing homes and raising the land high enough to safely redevelop on top of it.