Query the Southern Nevada Water Authority / LVVWD ArcGIS FeatureServer to determine a property's assigned outdoor-watering group

Steps

1. Note the service: https://maps.snwa.com/arcgis/rest/services/Common/Purveyor_and_Watering/FeatureServer (Service Item Id b50bb9015a26440cb7ac8a6e2e208f6b) exposes 4 layers — 0: LVVWD Watering Groups, 1: Service Areas (water purveyor by area), 2: SNWA Watering Zones, 3: LVVWD Watering Groups Union.
2. First query layer 1 (.../FeatureServer/1/query) with a point-in-polygon request (geometry=<lon,lat>&geometryType=esriGeometryPoint&inSR=4326&spatialRel=esriSpatialRelIntersects&outFields=PURVEYOR&f=json) to confirm the address is served by Las Vegas Valley Water District, since watering-group boundaries in this service only exist for LVVWD.
3. If LVVWD-served, run the same point-in-polygon query against layer 0 (.../FeatureServer/0/query) to get the property's assigned watering group back in the response attributes.
4. Map the returned group value to actual allowed days/times using LVVWD's published mandatory watering schedule (lvvwd.com/conservation/mandatory-watering-schedule) — the ArcGIS service gives the spatial assignment, not the day-of-week rules themselves.
5. Use f=geojson instead of f=json on any query if the consuming pipeline expects GeoJSON rather than Esri JSON.