sfgov/sfpuc-100year-storm-flood-hazard-zone-jzu3-4yxp

  • 100-year storm flood risk zone
  • hcr

SFPUC 100-Year Storm Flood Hazard Zone

SFPUC 100-Year Storm Flood Hazard Zone

This shapefile (polygon feature) contains the boundary of the July 1, 2019 100-Year Storm Flood Risk Zone, one of the layers of the July 1, 2019 100-Year Storm Flood Risk Map. The latest adoption FRRM flood map was adopted on July 2020. This adoption was also based on the July 2019 100-Year Storm Flood Risk Map analysis because this represents the latest analysis of the floodplain. No changes have occurred in the geographic extent of the flood plain map since 2019.

Areas within this boundary are highly likely to experience “deep and contiguous” flooding during a 100-year storm. A 100-year storm is a storm that has a 1% chance of occurring in a given year. “Deep and contiguous flooding” means flooding at least 6-inches deep spanning an area at least the size of half an average City block. The 100-Year Storm Flood Risk Zone does not provide the exact depth of flooding at a given location. It also does not show areas in the City that may experience shallower and/or more localized flooding in a 100-year storm, or areas of the City that may flood in storms larger than a 100-year storm. Finally, the 100-Year Storm Flood Risk Zone shows flood risk from storm runoff only. It does not consider flood risk in San Francisco from other causes such as inundation from the San Francisco Bay or Pacific Ocean. In addition to the 100-Year Storm Flood Risk Zone, the 100-Year Storm Flood Risk Map shows other layers. The layer “Areas not served by the Combined Sewer and Stormwater Collection System” shows where data for rainfall driven storm runoff is not available. A group of historical hydrology layers illustrate the general topography of low-lying areas in the City – “Historical Shoreline”, “Historical Creeks”, and “Historical Waterbodies”.

Columns

NameSocrata field nameColumn name in sgr mountData typeDescription
Shape_Lengshape_lengshape_lengNumberPlanar lengths of the polygon
the_geomthe_geomthe_geomMultiPolygonLocation Geometry
Shape_Areashape_areashape_areaNumberplanar area of the polygon

Upstream Metadata