e20xx, e19xx, series model is build as simple as possible, still powerful (e stands for ESRI based map )
California Flood MapOfficial california flood map is here. https://gis.bam.water.ca.gov/bam/
Now you can view these layers with this new model e2000https://transparentgov.net/json2tree/arcgis/js4/featurelayer_tree.html?layer_id=-99999&layer=am_viewer&url=https%3A%2F%2Fgis.water.ca.gov%2Farcgis%2Frest%2Fservices%2FBoundaries%2Fbam_viewer%2FMapServer&_center_zoom=16&_center_lat=34.049039&_center_long=-118.246521&select_item_id=5&select_item_text=FEMA+Effective&select_item_type=layer
https://transparentgov.net/json2tree/esri/server2/folder.html?org=https%3A%2F%2Fgis.water.ca.gov%2Farcgis%2Frest%2Fservices&url=https%3A%2F%2Fgis.water.ca.gov%2Farcgis%2Frest%2Fservices&arcgis_online_token=&select_folder=467&select_layer=-1
City of Palm Springs Tyler ERP enerGov MapServer
Now you can view these layers with this new model e2000
https://transparentgov.net/json2tree/arcgis/js4/featurelayer_tree.html?layer_id=-99999&layer=yler_ERP&url=https%3A%2F%2Fservices.arcgis.com%2Ff48yV21HSEYeCYMI%2Farcgis%2Frest%2Fservices%2FTyler_ERP%2FFeatureServer&_center_zoom=16&_center_lat=34.049039&_center_long=-118.246521&select_item_id=14&select_item_text=Neighborhoods&select_item_type=layer
https://transparentgov.net/json2tree/esri/server/folder.html?org=https%3A%2F%2Fservices.arcgis.com%2Ff48yV21HSEYeCYMI%2Farcgis%2Frest%2Fservices&url=https%3A%2F%2Fservices.arcgis.com%2Ff48yV21HSEYeCYMI%2Farcgis%2Frest%2Fservices&select_folder=2&select_layer=-1&arcgis_online_token=
NavigateLA ( City of Los Angeles, ca) MapServer has 432+ layers.
Department of Public Work, Bureau of Engineering, GIS division maintain these 400+ layers
Official site is here https://navigatela.lacity.org/navigatela/
https://transparentgov.net/json2tree/arcgis/js4/featurelayer_tree.html?layer_id=-99999&layer=avigateLA&url=https%3A%2F%2Fmaps.lacity.org%2Farcgis%2Frest%2Fservices%2FMapping%2FNavigateLA%2FMapServer&_center_zoom=17&_center_lat=34.049039&_center_long=-118.246521&select_item_id=411&select_item_text=LAPD+Divisions&select_item_type=layer
https://transparentgov.net/json2tree/esri/server2/folder.html?url=https%3A%2F%2Fmaps.lacity.org%2Farcgis%2Frest%2Fservices&org=Los+Angeles+CA+Public+Works+NavigateLA&_center_lat=34.049039&_center_long=-118.246521&_center_zoom=17&cross=default&timeout=3000&arcgis_online_token=&select_folder=19&select_layer=105