Scope freeze — water_quality_station Locationdex (10th Locationdex kind)

Frozen 2026-06-28. Source pasted by Mike: data.gov record for EPA ScienceHub DOI 10.23719/1407630, "Assessing Dungeness River BMP Effectiveness Using an Ecological Function Approach." Mike chose the shape: option A — an expandable water_quality_station kind (over a watershed-specific dungeness_water_quality kind).

What it is

An expandable, multi-study registry of measured water-quality monitoring stations. The slot is one fixed monitoring station; the STUDY / watershed it came from is a slot FIELD, not the key. This is the same registry shape Mike chose for coral_reef_station: future EPA water-quality studies (or a broader STORET/WQX pull) extend the SAME kind rather than minting a new one each time.

Slot = a monitoring station (Locationdex)

• Slot id: <study_id>-<station_id>, namespaced so a future study's station "716" can never overwrite this study's station 716.
• The place: station name, latitude, longitude, datum, org, state, county, HUC, station_type.
• Embedded measured record: a per-characteristic summary (n, detected vs non-detect counts, units, detected min/median/max, year range) plus the raw samples list. A precipitation station instead embeds annual precip totals (raw hourly is summarized, not embedded wholesale).

First study loaded — Dungeness River, WA (study_id = dungeness)

One small watershed near Sequim, WA (Clallam County, HUC 17110020), monitored by Clallam County, the Jamestown S'Klallam Tribe, WA Dept. of Ecology and EPA. 84 station slots:

• 80 STORET water-quality stations (station_type = water_quality), 1999-2014, ~16,500 grab-sample results across 316 characteristics (fecal coliform, water temperature, flow, nutrients, turbidity, pH, pesticide panels, ...).
• 1 USGS gauge USGS-12048000 (station_type = usgs_wq_gauge), water chemistry + flow back to 1959.
• 3 NOAA COOP precipitation gauges (station_type = precipitation), Port Angeles area, back to 1948.

Measured reality vs held out (bright line)

feedback_measured_reality_only. All three files are physical measurements: grab-sample lab/field results, gauge flow readings, rain-gauge precipitation.

• OUT — USGS rows whose method is "Computation by NWIS algorithm" (e.g. total dissolved solids computed from specific conductance, parameter 70301): an algorithm's estimate, not a measurement. 133 such rows dropped from the Dungeness USGS gauge; the count is recorded on the slot (n_computed_held_out). A measured TDS value (param 70300) is kept.

feedback_data_is_data_partial_coverage: non-detect samples are kept (value nulled, detect = "non-detect") rather than dropped; a station with no coordinates (the precip gauges) is kept with lat/lon null. Pesticide-screen stations that are almost entirely non-detect (e.g. station 716, 310 of 331 samples below quantification) are carried in full, the non-detection itself being a measured result.

Storage

Locationdex sibling storehouse data/location_storehouse/water_quality_station/<slot_id>.json, file-per-slot (84 slots), via event_storehouse.write_dossier + rebuild_index_from_disk. The build clears the kind dir first so removed/renamed slots never linger.

Expanding the kind

Add a sibling study by adding one entry to STUDIES (label, watershed, HUC, file URLs) and, if it is not STORET-shaped, a small reader feeding the shared summarize_characteristics / station_summary aggregators. Same-shaped studies (STORET WQX exports) need only the registry entry. Slot ids are namespaced by study_id, so studies never collide.

Deferred

• Coordinates for the 3 COOP precip gauges (the rainfall file carries no per-COOP lat/lon).
• Raw hourly precipitation (only annual totals embedded in v1).
• Cross-reference of USGS-12048000 to the streamgauge Locationdex slot for the same gauge.
• Sibling EPA water-quality studies / a broader STORET/WQX national pull (the point of option A).
• Spatial sweep / cross-match (deferred for every Locationdex kind until one needs it).
• No live edge: the Dungeness study is a closed 1948-2014 archive.