diff --git a/helper/geojsonify.js b/helper/geojsonify.js
index 3a97e047a..b049d1a51 100644
--- a/helper/geojsonify.js
+++ b/helper/geojsonify.js
@@ -6,6 +6,7 @@ const _ = require('lodash');
 const Document = require('pelias-model').Document;
 const codec = require('pelias-model').codec;
 const field = require('./fieldValue');
+const decode_gid = require('./decode_gid');
 
 function geojsonifyPlaces( params, docs ){
 
@@ -40,13 +41,14 @@ function geojsonifyPlaces( params, docs ){
 }
 
 function geojsonifyPlace(params, place) {
+  const gid_components = decode_gid(place._id);
   // setup the base doc
   const doc = {
-    id: place.source_id,
-    gid: new Document(place.source, place.layer, place.source_id).getGid(),
+    id: gid_components.id,
+    gid: new Document(place.source, place.layer, gid_components.id).getGid(),
     layer: place.layer,
     source: place.source,
-    source_id: place.source_id,
+    source_id: gid_components.id,
     bounding_box: place.bounding_box,
     lat: parseFloat(place.center_point.lat),
     lng: parseFloat(place.center_point.lon)
diff --git a/sanitizer/_ids.js b/sanitizer/_ids.js
index 89590ac35..873e45e3f 100644
--- a/sanitizer/_ids.js
+++ b/sanitizer/_ids.js
@@ -1,8 +1,7 @@
-var _ = require('lodash'),
-    check = require('check-types'),
-    type_mapping = require('../helper/type_mapping');
-
-var ID_DELIM = ':';
+const _ = require('lodash');
+const check = require('check-types');
+const type_mapping = require('../helper/type_mapping');
+const decode_gid = require('../helper/decode_gid');
 
 // validate inputs, convert types and apply defaults id generally looks like
 // 'geonames:venue:4163334' (source:layer:id) so, all three are required
@@ -18,23 +17,22 @@ var targetError = function(target, target_list) {
 };
 
 function sanitizeId(rawId, messages) {
-  var parts = rawId.split(ID_DELIM);
+  const gid = decode_gid(rawId);
 
-  if ( parts.length < 3 ) {
+  if (!gid ) {
     messages.errors.push( formatError(rawId) );
     return;
   }
 
-  var source = parts[0];
-  var layer = parts[1];
-  var id = parts.slice(2).join(ID_DELIM);
+  const { source, layer, id } = gid;
 
   // check if any parts of the gid are empty
   if (_.includes([source, layer, id], '')) {
     messages.errors.push( formatError(rawId) );
     return;
   }
-  var valid_values = Object.keys(type_mapping.source_mapping);
+
+  const valid_values = Object.keys(type_mapping.source_mapping);
   if (!_.includes(valid_values, source)) {
     messages.errors.push( targetError(source, valid_values) );
     return;
diff --git a/test/unit/fixture/dedupe_elasticsearch_results.js b/test/unit/fixture/dedupe_elasticsearch_results.js
index 656730521..eb0c85e67 100644
--- a/test/unit/fixture/dedupe_elasticsearch_results.js
+++ b/test/unit/fixture/dedupe_elasticsearch_results.js
@@ -57,7 +57,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'node:357289197',
     'category': [
       'education'
     ],
@@ -118,7 +117,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5219083',
     'category': [
       'education'
     ],
@@ -197,7 +195,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5183465',
     'category': [
       'entertainment',
       'recreation'
@@ -277,7 +274,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'node:368338500',
     'category': [
       'education'
     ],
@@ -339,7 +335,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'way:84969670',
     'category': [
       'education'
     ],
@@ -409,7 +404,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5192545',
     'category': [
       'education'
     ],
@@ -488,7 +482,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5198085',
     'category': [
       'education'
     ],
@@ -558,7 +551,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5208101',
     'category': [
       'education'
     ],
@@ -638,7 +630,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'way:161088588',
     'category': [
       'education'
     ],
@@ -717,7 +708,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5200263',
     'category': [
       'education'
     ],
@@ -788,7 +778,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'way:34212977',
     'category': [
       'education'
     ],
@@ -867,7 +856,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'node:357330916',
     'category': [
       'education'
     ],
@@ -937,7 +925,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'openstreetmap',
-    'source_id': 'node:357330919',
     'category': [
       'education'
     ],
@@ -1007,7 +994,6 @@ module.exports = [
     'address_parts': {},
     'alpha3': 'USA',
     'source': 'geonames',
-    'source_id': '5197082',
     'category': [
       'education'
     ],
diff --git a/test/unit/helper/geojsonify.js b/test/unit/helper/geojsonify.js
index 8e3ebe414..1f1523f0e 100644
--- a/test/unit/helper/geojsonify.js
+++ b/test/unit/helper/geojsonify.js
@@ -12,14 +12,15 @@ module.exports.tests.interface = function(test, common) {
   });
 };
 
+// ensure null island coordinates work
 // ref: https://github.com/pelias/pelias/issues/84
 module.exports.tests.earth = function(test, common) {
   test('earth', function(t) {
     var earth = [{
-      '_id': '6295630',
+      '_type': 'doc',
+      '_id': 'whosonfirst:continent:6295630',
       'source': 'whosonfirst',
       'layer': 'continent',
-      'source_id': '6295630',
       'name': {
         'default': 'Earth'
       },
@@ -41,9 +42,8 @@ module.exports.tests.all = (test, common) => {
   test('bounding_box should be calculated using points when avaiable', t => {
     const input = [
       {
-        _id: 'id 1',
+        _id: 'source 1:layer 1:id 1',
         source: 'source 1',
-        source_id: 'id 1',
         layer: 'layer 1',
         name: {
           default: 'name 1',
@@ -54,9 +54,8 @@ module.exports.tests.all = (test, common) => {
         }
       },
       {
-        _id: 'id 2',
+        _id: 'source 2:layer 2:id 2',
         source: 'source 2',
-        source_id: 'id 2',
         layer: 'layer 2',
         name: {
           default: 'name 2',
@@ -70,12 +69,12 @@ module.exports.tests.all = (test, common) => {
 
     const geojsonify = proxyquire('../../../helper/geojsonify', {
       './geojsonify_place_details': (params, source, dst) => {
-        if (source._id === 'id 1') {
+        if (source._id === 'source 1:layer 1:id 1') {
           return {
             property1: 'property 1',
             property2: 'property 2'
           };
-        } else if (source._id === 'id 2') {
+        } else if (source._id === 'source 2:layer 2:id 2') {
           return {
             property3: 'property 3',
             property4: 'property 4'
@@ -136,9 +135,8 @@ module.exports.tests.all = (test, common) => {
   test('bounding_box should be calculated using polygons when avaiable', t => {
     const input = [
       {
-        _id: 'id 1',
+        _id: 'source 1:layer 1:id 1',
         source: 'source 1',
-        source_id: 'id 1',
         layer: 'layer 1',
         name: {
           default: 'name 1',
@@ -155,9 +153,8 @@ module.exports.tests.all = (test, common) => {
         }
       },
       {
-        _id: 'id 2',
+        _id: 'source 2:layer 2:id 2',
         source: 'source 2',
-        source_id: 'id 2',
         layer: 'layer 2',
         name: {
           default: 'name 2',
@@ -177,12 +174,12 @@ module.exports.tests.all = (test, common) => {
 
     const geojsonify = proxyquire('../../../helper/geojsonify', {
       './geojsonify_place_details': (params, source, dst) => {
-        if (source._id === 'id 1') {
+        if (source._id === 'source 1:layer 1:id 1') {
           return {
             property1: 'property 1',
             property2: 'property 2'
           };
-        } else if (source._id === 'id 2') {
+        } else if (source._id === 'source 2:layer 2:id 2') {
           return {
             property3: 'property 3',
             property4: 'property 4'
@@ -245,7 +242,7 @@ module.exports.tests.all = (test, common) => {
   test('bounding_box should be calculated using polygons AND points when avaiable', t => {
     const input = [
       {
-        _id: 'id 1',
+        _id: 'source 1:layer 1:id 1',
         source: 'source 1',
         source_id: 'id 1',
         layer: 'layer 1',
@@ -258,9 +255,8 @@ module.exports.tests.all = (test, common) => {
         }
       },
       {
-        _id: 'id 2',
+        _id: 'source 2:layer 2:id 2',
         source: 'source 2',
-        source_id: 'id 2',
         layer: 'layer 2',
         name: {
           default: 'name 2',
@@ -280,12 +276,12 @@ module.exports.tests.all = (test, common) => {
 
     const geojsonify = proxyquire('../../../helper/geojsonify', {
       './geojsonify_place_details': (params, source, dst) => {
-        if (source._id === 'id 1') {
+        if (source._id === 'source 1:layer 1:id 1') {
           return {
             property1: 'property 1',
             property2: 'property 2'
           };
-        } else if (source._id === 'id 2') {
+        } else if (source._id === 'source 2:layer 2:id 2') {
           return {
             property3: 'property 3',
             property4: 'property 4'
@@ -354,9 +350,8 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
       null,
       undefined,
       {
-        _id: 'id 1',
+        _id: 'source 1:layer 1:id 1',
         source: 'source 1',
-        source_id: 'id 1',
         layer: 'layer 1',
         name: {
           default: 'name 1',
@@ -370,7 +365,7 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
 
     const geojsonify = proxyquire('../../../helper/geojsonify', {
       './geojsonify_place_details': (params, source, dst) => {
-        if (source._id === 'id 1') {
+        if (source._id === 'source 1:layer 1:id 1') {
           return {
             property1: 'property 1',
             property2: 'property 2'
@@ -417,18 +412,16 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
 
     const input = [
       {
-        _id: 'id 1',
+        _id: 'source 1:layer 1:id 1',
         source: 'source 1',
-        source_id: 'id 1',
         layer: 'layer 1',
         name: {
           default: 'name 1',
         }
       },
       {
-        _id: 'id 2',
+        _id: 'source 2:layer 2:id 2',
         source: 'source 2',
-        source_id: 'id 2',
         layer: 'layer 2',
         name: {
           default: 'name 2',
@@ -442,7 +435,7 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
 
     const geojsonify = proxyquire('../../../helper/geojsonify', {
       './geojsonify_place_details': (params, source, dst) => {
-        if (source._id === 'id 2') {
+        if (source._id === 'source 2:layer 2:id 2') {
           return {
             property3: 'property 3',
             property4: 'property 4'
@@ -489,9 +482,8 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
 
     const input = [
       {
-        _id: 'id 1',
+        _id: 'source 1:layer 1:id 1',
         source: 'source 1',
-        source_id: 'id 1',
         layer: 'layer 1',
         center_point: {
           lat: 12.121212,
@@ -499,9 +491,8 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
         }
       },
       {
-        _id: 'id 2',
+        _id: 'source 2:layer 2:id 2',
         source: 'source 2',
-        source_id: 'id 2',
         layer: 'layer 2',
         name: {},
         center_point: {
@@ -510,9 +501,8 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
         }
       },
       {
-        _id: 'id 3',
+        _id: 'source 3:layer 3:id 3',
         source: 'source 3',
-        source_id: 'id 3',
         layer: 'layer 3',
         name: {
           default: 'name 3',
@@ -526,17 +516,17 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
 
     const geojsonify = proxyquire('../../../helper/geojsonify', {
       './geojsonify_place_details': (params, source, dst) => {
-        if (source._id === 'id 1') {
+        if (source._id === 'source 1:layer 1:id 1') {
           return {
             property1: 'property 1',
             property2: 'property 2'
           };
-        } else if (source._id === 'id 2') {
+        } else if (source._id === 'source 2:layer 2:id 2') {
           return {
             property3: 'property 3',
             property4: 'property 4'
           };
-        } else if (source._id === 'id 3') {
+        } else if (source._id === 'source 3:layer 3:id 3') {
           return {
             property5: 'property 5',
             property6: 'property 6'
@@ -643,10 +633,9 @@ module.exports.tests.non_optimal_conditions = (test, common) => {
 module.exports.tests.nameAliases = function(test, common) {
   test('name aliases', function(t) {
     var aliases = [{
-      '_id': '1',
+      '_id': 'example:example:1',
       'source': 'example',
       'layer': 'example',
-      'source_id': '1',
       'name': {
         'default': ['Example1', 'Example2'] // note the array
       },
@@ -687,10 +676,9 @@ module.exports.tests.nameAliases = function(test, common) {
 module.exports.tests.addendum = function(test, common) {
   test('addendum: not set in source', function(t) {
     var example = [{
-      '_id': '6295630',
+      '_id': 'whosonfirst:continent:6295630',
       'source': 'whosonfirst',
       'layer': 'continent',
-      'source_id': '6295630',
       'name': {
         'default': 'Earth'
       },
@@ -704,12 +692,12 @@ module.exports.tests.addendum = function(test, common) {
     t.false(collection.features[0].properties.addendum);
     t.end();
   });
+
   test('addendum: set in source', function(t) {
     var example = [{
-      '_id': '6295630',
+      '_id': 'whosonfirst:continent:6295630',
       'source': 'whosonfirst',
       'layer': 'continent',
-      'source_id': '6295630',
       'name': {
         'default': 'Earth'
       },
@@ -730,12 +718,12 @@ module.exports.tests.addendum = function(test, common) {
     });
     t.end();
   });
+
   test('addendum: partially corrupted', function(t) {
     var example = [{
-      '_id': '6295630',
+      '_id': 'whosonfirst:continent:6295630',
       'source': 'whosonfirst',
       'layer': 'continent',
-      'source_id': '6295630',
       'name': {
         'default': 'Earth'
       },
@@ -757,7 +745,7 @@ module.exports.tests.addendum = function(test, common) {
   });
   test('addendum: all corrupted', function(t) {
     var example = [{
-      '_id': '6295630',
+      '_id': 'whosonfirst:continent:6295630',
       'source': 'whosonfirst',
       'layer': 'continent',
       'source_id': '6295630',