Seattle Slope & Wall

Seattle public GIS

Seattle ECA map and layer guide.

How to check the city's environmentally critical area layers, download the address-level Site Characteristics Report, and understand what neither source can establish by itself.

Check a Seattle address in three steps

  1. Open the official ECA map

    Search the address in the SDCI Property Information Map ↗ and turn on the relevant environmentally critical area layers. Treat a mapped flag as a screening signal, not a surveyed boundary or stability finding.

  2. Download the Site Characteristics Report

    Use SDCI's Permit & Site History Research Tool ↗ to locate the development site and download its current report. Review related addresses, zoning overlays, permit history and available documents together.

  3. Move from screening to the project path

    Map layers and reports do not approve a wall or diagnose a slope. Continue with the Seattle ECA retaining-wall guide, then decide whether the first call belongs with an engineer, contractor or agency and trace any proposed outlet with the Seattle wall-drainage guide.

What the aggregates describe

Each neighborhood profile intersects an official Neighborhood Map Atlas polygon with four Seattle environmentally critical area layers: steep slope, potential slide areas, properties associated with known slides, and liquefaction-prone areas. It also counts known-slide initiation points inside the same neighborhood polygon and reports event years when the source carries a usable date.

Percentages are calculated from simplified GeoJSON at refresh time and rounded to two decimal places. Boundaries overlap imperfectly with everyday neighborhood usage and permit labels. Use the values to understand the citywide record, not to rank homes, predict a slide, or decide whether engineering is required.

Planning a retaining-wall repair or replacement on a flagged site? Read the Seattle ECA and steep-slope wall guide for the permit test, map limitations, relief paths, survey and geotechnical roles, drainage, and rainy-season review.

For an existing wall rather than a new project, the rainy-season maintenance checklist separates accessible drainage upkeep, observation records and concerns that need professional evaluation. Neither maintenance nor a map result establishes that a wall is safe.

Neighborhood layer profiles

Each ECA aggregate now lives in the single combined profile for that Seattle neighborhood. These links open the layer section directly; there is no separate set of duplicate slope-detail pages.

01Alki22.11% mapped steep slope→02Fauntleroy21.12% mapped steep slope→03Riverview18.91% mapped steep slope→04Briarcliff18.57% mapped steep slope→05Broadview18.55% mapped steep slope→06North Admiral18.32% mapped steep slope→07Leschi17.27% mapped steep slope→08West Queen Anne17.14% mapped steep slope→09East Queen Anne16.22% mapped steep slope→10Highland Park15.51% mapped steep slope→11Sunset Hill15.04% mapped steep slope→12Cedar Park14.89% mapped steep slope→13Rainier View14.79% mapped steep slope→14South Beacon Hill14.65% mapped steep slope→15Harrison/Denny-Blaine14.38% mapped steep slope→16Seaview13.78% mapped steep slope→17North Delridge13.45% mapped steep slope→18Lawton Park12.48% mapped steep slope→19Madrona12.07% mapped steep slope→20Rainier Beach11.96% mapped steep slope→21Mount Baker10.22% mapped steep slope→22North Beacon Hill10.19% mapped steep slope→23Stevens9.77% mapped steep slope→24North Queen Anne9.37% mapped steep slope→25Mid-Beacon Hill9% mapped steep slope→26Arbor Heights8.83% mapped steep slope→27Broadway8.02% mapped steep slope→28Matthews Beach7.85% mapped steep slope→29Gatewood7.26% mapped steep slope→30Interbay7.12% mapped steep slope→31Columbia City6.64% mapped steep slope→32Windermere6.46% mapped steep slope→33Southeast Magnolia6.32% mapped steep slope→34Fairmount Park5.72% mapped steep slope→35Laurelhurst5.46% mapped steep slope→36Wedgwood5.27% mapped steep slope→37Phinney Ridge4.69% mapped steep slope→38First Hill4.24% mapped steep slope→39Fremont4.24% mapped steep slope→40Genesee4.02% mapped steep slope→41Ravenna3.61% mapped steep slope→42Pinehurst2.59% mapped steep slope→43University Heights1.95% mapped steep slope→44Greenwood1.88% mapped steep slope→45Green Lake1.65% mapped steep slope→46Wallingford1.55% mapped steep slope→47Bryant1.46% mapped steep slope→48Madison Park0.86% mapped steep slope→49Loyal Heights0.16% mapped steep slope→