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Age of Imperviousness

Impervious surface by estimated date of conversion. Used to estimate level of current stormwater treatment.


This layer provides multi-temporal information on the presence of built-up surfaces derived from global Landsat satellite data collected from 1975 to 2014. The base image data collections were prepared by the Global Land Survey and the Joint Research Center. The data was processed by fully automatic and reproducible methods based on statistical learning (Symbolic Machine Learning. The source product was developed with a spatial resolution of 30 meters. To provide a finer resolution for the stormwater heatmap, the source product was masked by 1-meter resolution imperviousness data developed by the Nature Conservancy.

Layer Access in Earth Engine

The javascript commands below can be used to access this layer within the Google Earth Engine Code Editor. A Google Earth Engine account is required.

// Import the layer data dictionary
var data = require('users/stormwaterheatmap/apps:data/public')

// To view data dictionary, print to the console:
print('Data:', data)

//Get this layer from the layer data dictionary:
var layer_name = data.rasters["Age of Imperviousness"]


Individual objects contain all the info used in the stormwater heatmap. To add it to the map, add the layer object.

var display_image = layer_name.layer


To get the raw image data for analysis, access the eeObject key.

var raw_image = layer_name.layer.eeObject
Map.addLayer(raw_image,{},'Age of Imperviousness')



LabelRaster valueColors
2000–2014 (stormwater likely treated)39e+739e+73
1990–2000 (some stormwater treatment)4F0E442F0E442
Before 1990 (likely no stormwater treatment)5CC6677CC6677


The Nature Conservancy; Columbia University, Center for International Earth Science Information Network