Landslide maps are planning clues, not live warnings

Watch the slope itself. Warning signs include cracks, bulges, rumbles, or a slope that sheds material. New water seepage can also be a sign. So can tilting trees or poles, pulled utility lines, or doors and windows that start to stick.

If you see these signs, contact local officials. Leave at once if it is safe. Call 911 for danger now. If a slide is already hitting the building, do not cross it. USGS says to stay inside and move to a higher floor or onto a countertop.

Use the California Geological Survey tools for planning, not a live choice. The inventory shows past slides that have been mapped. It does not say how likely a slide is in the gaps. The reported-slide database is still growing and is not updated in real time.

Map Sheet 58 uses regional slope and rock data. It shows relative susceptibility to deep-seated slides. It cannot decide the risk at one site. The layer does not model a current storm or quake. It also misses some shallow slides, debris flows, rockfalls, burned-slope risks, walls, drains, road cuts, and foundations. A blank or pale spot is not a safety clearance.

For a property or permit choice, ask the local building or public works office about the real slope. Also ask a California-licensed geologist or a qualified engineer. During storms or after a fire, use current county alerts, road closures, and evacuation steps. Do not wait for the map to change.