Del Mar is a small city with an unusual number of natural edges. There’s the beach and the river mouth to the north, bluffs along the shore, canyons inland, and hillsides throughout. Each of those edges has a map somewhere that describes its hazard. For an owner, the challenge isn’t finding the maps. It’s knowing what each one is for, and what it leaves out.
These notes walk through the main maps that touch Del Mar parcels and what they suggest about the structure on the lot.
What the City’s own plan says
The County’s 2023 hazard mitigation plan includes an annex for the City of Del Mar. It rates earthquake, erosion, flood, sea level rise, tsunami and wildfire as high hazards for the city, with expansive soils and landslide rated medium. That’s a long list for a city of this size, and it explains why no single map tells the whole story.
The annex also describes where these hazards concentrate: the North Beach floodplain, the coastal bluffs to the north and south, the canyon areas such as Crest Canyon with very high fire hazard severity, and inland bluff erosion in the North and South Hills. It notes the City’s restriction on development within 40 feet of a coastal bluff edge, and that real estate disclosure applies for properties in the Floodplain and Coastal Bluff overlay zones.
Flood maps
The federal flood maps are the most consequential for many owners, because they affect insurance and building requirements.
According to the City’s page on the new flood map, Del Mar participates in the National Flood Insurance Program, and the City regulates the Special Flood Hazard Area, the area with a 1 percent annual chance of flooding, as its Floodplain Overlay Zone. A FEMA coastal study led to a new Flood Insurance Rate Map that became effective on December 21, 2019, on panels 06073C1307 and 06073C1309.
A few points from that page are worth keeping in mind:
- The new maps model wave action, dune erosion, wave run-up and overtopping of seawalls.
- They do not model projected sea level rise.
- The VE zone, the coastal high hazard area, was extended east past the seawalls onto beachfront property north of 18th Street up to the San Dieguito Lagoon river mouth.
- Owners who believe their property was mapped incorrectly can request a letter of map change from FEMA.
- Federally backed mortgages on buildings in the Special Flood Hazard Area require flood insurance.
FEMA’s Flood Map Service Center lets anyone look up the effective map for an address. Our earlier note on the VE zone goes deeper into what that designation means for beachfront foundations; our North Beach floodplain foundations page covers the structural side.
Earthquake maps
The California Geological Survey publishes Earthquake Zones of Required Investigation through its EQ Zapp tool. These zones flag areas where state law requires site investigation for fault rupture, liquefaction or earthquake-induced landslides before certain development.
We won’t characterize which zones touch which Del Mar parcels; that’s a parcel-by-parcel lookup, and the map is the authority. What’s useful to know is what a zone means. If a parcel falls in one, a geotechnical investigation addressing that hazard is typically part of new construction or significant work. If it doesn’t, the absence of a zone doesn’t mean the ground is free of seismic risk. The whole region shakes.
Fire, and the combined view
Cal OES’s MyHazards tool pulls several hazard layers into one place: flood, fire, earthquake and tsunami among them. It’s a convenient first look for owners who want to see which categories apply to their address.
For fire, the canyon areas matter most in Del Mar. Fire hazard is mostly a question of vegetation, defensible space and construction materials rather than foundations, but after a fire, slopes can change. Burned hillsides can shed debris and water differently, which can affect retaining walls and drainage below them.
Sea level rise
NOAA’s Sea Level Rise Viewer shows how different amounts of rise would affect the shoreline. It’s a planning tool, not a regulatory map. It doesn’t determine insurance or permits. But for a beachfront or lagoon-edge owner thinking about the next few decades, it’s a sobering and useful view. The City’s own planning on this subject is covered in our earlier note on Del Mar’s sea level rise plan.
What the maps can’t tell you
Every map here works at a scale broader than a single house. None of them knows:
- How your foundation was built or what condition it’s in.
- Whether there’s undocumented fill under part of the lot.
- How water actually moves across your parcel in a heavy storm.
- Whether a retaining wall or bluff-top improvement is performing as intended.
- What past repairs were made, and how well.
Maps tell you which questions to ask. The answers come from records, soils reports and looking at the structure itself.
Reading the maps as a set
For a Del Mar parcel, a sensible sequence:
- Look up the effective flood map on FEMA’s Flood Map Service Center.
- Check MyHazards for a combined overview.
- Check EQ Zapp for any Earthquake Zone of Required Investigation.
- Review the City’s zoning and overlay information for the parcel, including any Floodplain or Coastal Bluff overlay.
- Look at NOAA’s Sea Level Rise Viewer if the parcel is near the beach or lagoon.
- Gather the property’s permit records and any geotechnical reports.
- Then have the structure reviewed with those findings in mind.
How we help
We review foundations, slopes, retaining walls and drainage with the parcel’s mapped hazards in view, and we coordinate with licensed engineers as needed, along with geotechnical professionals where soils or bluff conditions call for it. Our bluff and hillside homes page describes that work, and a foundation inspection is often the right first step before a purchase or project. Cost depends on the parcel’s setting, access, the size of the structure and the records available, and we explain those factors after an initial look. We serve the whole City of Del Mar.
If you’ve received a disclosure packet or are planning work and want the maps translated into structural questions, ask for a Free Quote.