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.

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 slope02Fauntleroy21.12% mapped steep slope03Riverview18.91% mapped steep slope04Briarcliff18.57% mapped steep slope05Broadview18.55% mapped steep slope06North Admiral18.32% mapped steep slope07Leschi17.27% mapped steep slope08West Queen Anne17.14% mapped steep slope09East Queen Anne16.22% mapped steep slope10Highland Park15.51% mapped steep slope11Sunset Hill15.04% mapped steep slope12Cedar Park14.89% mapped steep slope13Rainier View14.79% mapped steep slope14South Beacon Hill14.65% mapped steep slope15Harrison/Denny-Blaine14.38% mapped steep slope16Seaview13.78% mapped steep slope17North Delridge13.45% mapped steep slope18Lawton Park12.48% mapped steep slope19Madrona12.07% mapped steep slope20Rainier Beach11.96% mapped steep slope21Mount Baker10.22% mapped steep slope22North Beacon Hill10.19% mapped steep slope23Stevens9.77% mapped steep slope24North Queen Anne9.37% mapped steep slope25Mid-Beacon Hill9% mapped steep slope26Arbor Heights8.83% mapped steep slope27Broadway8.02% mapped steep slope28Matthews Beach7.85% mapped steep slope29Gatewood7.26% mapped steep slope30Interbay7.12% mapped steep slope31Columbia City6.64% mapped steep slope32Windermere6.46% mapped steep slope33Southeast Magnolia6.32% mapped steep slope34Fairmount Park5.72% mapped steep slope35Laurelhurst5.46% mapped steep slope36Wedgwood5.27% mapped steep slope37Phinney Ridge4.69% mapped steep slope38First Hill4.24% mapped steep slope39Fremont4.24% mapped steep slope40Genesee4.02% mapped steep slope41Ravenna3.61% mapped steep slope42Pinehurst2.59% mapped steep slope43University Heights1.95% mapped steep slope44Greenwood1.88% mapped steep slope45Green Lake1.65% mapped steep slope46Wallingford1.55% mapped steep slope47Bryant1.46% mapped steep slope48Madison Park0.86% mapped steep slope49Loyal Heights0.16% mapped steep slope