# N05_E18 Great Lakes pilot: water-quality monitoring bridge **Research date:** 2026-08-06 **Canonical sector:** `N05_E18` **Grid:** 24 × 24; latitude 37.5°–45.0° N; longitude 270°–285° E (75°–90° W) **Pilot position:** Great Lakes nine-sector octagon centered on the N05_E18 working anchor at Merrillville, Indiana **Research status:** Active bridge extension; not a completed sector audit **Time band:** 1950–present, with machine-readable monitoring records from 1970–2024 and a local historical source published in 1966 ## Scope and selection This run continues the Great Lakes pilot and does not expand globally. It follows the next search path in the existing N05_E18 water/industrial bridge note: add a modern, machine-readable water-quality series while preserving station coordinates, analytes, units, detection conditions, and missingness; then add an archival local record for institutional and transport context. The sources do not cover the fixed cell uniformly. They represent point monitoring locations, small river reaches, and a local historical narrative. They are therefore evidence about parts of the sector and its connected corridor, not cell-wide values. ## Raw observations ### A. Water Quality Portal station metadata The U.S. Water Quality Portal (WQP) integrates discrete water-quality records from USGS, EPA, and other agencies. Station metadata were retrieved in CSV format on 2026-08-06. | Monitoring location | Direct source name | Coordinates (NAD83) | HUC-8 | Drainage area | Geographic relation to `N05_E18` | |---|---|---:|---|---:|---| | `USGS-04093200` | Little Calumet River at Gary, IN | 41.57198089, -87.32031510 | 04040001 | 5.82 sq mi | Point station on a small river reach; not cell-wide | | `USGS-05536356` | Grand Calumet River at Columbia Av at Hammond, IN | 41.61861110, -87.49983330 | 07120003 | Not reported in returned row | Point station on the industrial corridor; not cell-wide | | `USGS-04092800` | Lake Michigan at filtration plant at Gary, IN | 41.63392496, -87.36198370 | 04060200 | Not reported in returned row | Nearshore point station; not a lakewide or cell-area measure | The returned station records identify the provider as the USGS Indiana Water Science Center and the portal provider as `NWIS`. The coordinates and source boundaries should be retained in any later spatial crosswalk rather than assigned to the sector centroid. ### B. Machine-readable result coverage Result queries used the WQP CSV endpoint with `sampleMedia=Water`, `mimeType=csv`, and `zip=no`. The retrieval was not treated as a complete inventory of all possible records outside the portal’s returned profile. | Site | Returned result rows | Returned date range | Unique sampling dates | Coverage observation | |---|---:|---|---:|---| | `USGS-04093200` | 60 | 1979-12-11 to 1980-04-08 | 3 | One bed-sediment sampling date and two water-sampling dates in the returned profile | | `USGS-05536356` | 849 | 2021-05-24 to 2024-02-22 | 40 | Modern structured records concentrated in 2021–2024 | | `USGS-04092800` | 8 | 1970-10-13 only | 1 | Single returned water-sampling date | The absence of returned rows in other periods is coded as bounded search coverage (`searched_no_result` for the query), not as evidence that no monitoring, pollution, or remediation existed. The WQP homepage notes that its legacy interface contains a profile limitation for recent USGS data; this is an additional reason not to treat portal silence as a historical zero. ### C. Selected reported results at `USGS-04093200` The WQP result file contains a small 1979–1980 sample set with both bed-sediment and water results. These are reported values from the source table, not period means. | Date | Medium/fraction | Characteristic | Reported value | Unit | |---|---|---|---:|---| | 1979-12-11 | Bed sediment | Lead | 150 | mg/kg | | 1979-12-11 | Bed sediment | Zinc | 230 | mg/kg | | 1979-12-11 | Bed sediment | Polychlorinated biphenyls | 79 | µg/kg | | 1979-12-11 | Bed sediment | Chlordane, technical | 110 | µg/kg | | 1980-04-07 | Water | Temperature | 15.2 | deg C | | 1980-04-07 | Water | Specific conductance | 1,140 | µS/cm @25C | | 1980-04-07 | Water | Dissolved oxygen | 9.7 | mg/L | | 1980-04-07 | Water | pH | 7.7 | standard units | | 1980-04-08 | Water | Temperature | 11.2 | deg C | | 1980-04-08 | Water | Specific conductance | 778 | µS/cm @25C | | 1980-04-08 | Water | Dissolved oxygen | 4.9 | mg/L | | 1980-04-08 | Water | pH | 7.3 | standard units | | 1980-04-08 | Water | Chromium | 27 | µg/L | | 1980-04-08 | Water | Copper | 80 | µg/L | | 1980-04-08 | Water | Iron | 360 | µg/L | | 1980-04-08 | Water | Lead | 600 | µg/L | | 1980-04-08 | Water | Manganese | 150 | µg/L | | 1980-04-08 | Water | Zinc | 510 | µg/L | The source also reports `Cadmium` as **Detected Not Quantified** on 1980-04-08. That result is retained as a detection-condition observation without converting it into a numeric value. The two dissolved-oxygen values, two pH values, and two conductance values are not averaged because they are separate samples on separate dates and no period aggregation rule has been approved for this pilot. ### D. Selected reported results at `USGS-04092800` The single returned date, 1970-10-13, includes the following reported results from the Lake Michigan filtration-plant location: - Chromium(VI): `1 µg/L as Cr` (dissolved). - Mercury: `0.00 µg/L` (dissolved) and `0.8 µg/L` (recoverable). - Lead: **Detected Not Quantified** (dissolved). - Arsenic, cadmium, cobalt, and zinc were returned with reported numeric values of `0.0 µg/L` in the source row. The reported `0.0` fields are not treated as proof of absence, a clean-water score, or a zero exposure. The result table’s detection, method, and sampling context must be reviewed before any interpretation. The single date is not a time series. ### E. Modern records at `USGS-05536356` The returned 849-row profile for the Grand Calumet River at Columbia Avenue covers 40 sampling dates from 2021-05-24 through 2024-02-22. The rows include physical, chemical, and biological/result-characteristic records. The result count is a coverage observation, not a concentration summary: analytes, fractions, methods, and units differ across rows and were not collapsed into a composite index. ### F. Archive.org local institutional and transport context The Internet Archive item **Reports And Papers Of Lake County Indiana (1958-1966)** is a 1966 compilation by the Lake County Public Library. In the section **“History of Dyer,”** printed pp. 67–68, P. T. Gettler reports: 1. By the early twentieth century, Dyer had the services of three railroads, after the Monon and E.J.&E. lines were added to an earlier line (printed p. 67). 2. A municipal water utility was established in 1915, supplied by a driven well, with a stated minimum quarterly rate and volume (printed p. 67). 3. The local narrative says that, during the machine-age period after World War I, the majority of Dyer workmen were employed by industries in the Calumet region (printed p. 68). 4. The same narrative attributes accelerated growth of communities on the industrial area’s fringe to World War II and states that the 1960 census placed Dyer’s population above 4,000 (printed p. 68). 5. The author describes local responses including police, fire protection, paved streets, street lighting, garbage collection, supermarkets, churches, and participation in the St. John Township school system (printed pp. 68–69). These are bounded observations from a local historical compilation. They are not an official census extract, a complete employment series, or proof that the entire `N05_E18` cell shared Dyer’s conditions. The water utility and railroad statements provide historical institutional/connectivity anchors for the corridor; the employment and population statements require independent census and labor-series verification before quantitative use. ## Source interpretation The WQP results provide a defensible modern/historical monitoring bridge in a limited sense: - The 1970 and 1979–1980 records show that chemically detailed monitoring existed at selected Calumet-area points during the historical bridge period. - The 1979–1980 Little Calumet sample includes bed-sediment metals and organochlorine/PCB observations alongside water chemistry. The reported values are heterogeneous and cannot be treated as one pollution index without a pre-specified analyte, medium, method, and normalization rule. - The 2021–2024 Grand Calumet profile demonstrates a substantial modern structured record at a relevant industrial-corridor station, but its results require an analyte-level extraction and spatial/time crosswalk before comparison with 1965 observations. - The 1966 local compilation links rail access, municipal water provision, industrial employment, and suburban growth in a near-contemporary historical narrative. It supports institutional-context research, not a sector-wide adaptation score. Together, the sources strengthen the case for a documented water–industry–connectivity interaction in parts of the Great Lakes pilot. They do not establish causal direction, a cell-wide pollution burden, remediation effectiveness, or a cultural classification. Capital, corporate location decisions, labor, state and federal regulation, transport technology, migration, and local governance remain alternative explanatory layers. ## Derived profile (not a quadrant) ### Derivation D1 — monitoring coverage summary - **Formula:** count returned WQP result rows, distinct sampling dates, and inclusive date range separately for each named site. - **Missing-data behavior:** no imputation; no assumption that unreturned periods are zero or unmonitored everywhere. - **Result:** the three queried sites returned 60, 849, and 8 rows respectively, with date ranges shown above. - **Interpretation limit:** row counts are not comparable measures of water quality because the sites differ in sampling design, analytes, media, methods, and date coverage. ### Derivation D2 — archival-to-modern variable crosswalk No numeric score was calculated. The following crosswalk is the current model-layer boundary: | Variable | Historical evidence | Modern structured evidence | Comparability | |---|---|---|---| | Water chemistry | 1965 agency report; 1970 and 1980 WQP samples | 2021–2024 WQP result profile | Related but not equivalent until analyte/method/time harmonization | | Sediment contamination | 1979 bed-sediment metals, PCB, and pesticide observations | No comparable modern sediment extraction in this run | Not comparable in this record | | Industrial water dependence | 1965 report’s basin/industry pumpage figures | No modern sector-level industrial withdrawal value extracted here | Related but not equivalent | | Connectivity | 1966 local account of three railroads; 1965 navigation context | No modern rail/port network extraction in this run | Related but not equivalent | | Municipal infrastructure | 1915 Dyer water utility and later local services, as reported in 1966 | No modern utility-capacity measure extracted here | Related but not equivalent | No composite constraint score or adaptive-capacity score was calculated. The Great Lakes formula remains unfrozen, source footprints are heterogeneous, and the monitoring record is not complete enough for a defensible cell-level derivation. ## Model classification ```yaml provisional_quadrant: unresolved classification_reason: > The run adds provenance-bearing monitoring and local institutional evidence, but the observations are point-specific, heterogeneous, and temporally discontinuous. A formula-governed sector classification would require harmonized analytes, spatial crosswalks, modern population/employment/ infrastructure data, and explicit missingness handling. formula_version: not_assigned confidence: medium for the named source observations; low for sector-wide inference ``` `provisional_quadrant` is a model output and is not an archival fact. This run does not assign one. ## Confidence and missingness ### Confidence dimensions - **Source authority:** high for WQP station/result records as records of what the source reports; medium for the 1966 local compilation as a historical narrative and locator. - **Geographic fit:** medium-low. All WQP records are point locations; the historical Dyer account is local; none is an area-weighted cell measure. - **Temporal fit:** medium for the 1970 and 1979–1980 anchors and 2021–2024 modern profile; lower for any continuous 1950–2000 inference. - **Measurement quality:** high for the machine-readable fields as transmitted by WQP; medium for interpretation because methods, detection limits, fractions, and sampling designs differ. - **Extraction quality:** high for the CSV row counts and selected fields; medium for the local history because the source is OCR-backed and the narrative requires scan/page verification for any central quantitative claim. - **Independent corroboration:** low to medium. The 1965 pollution report already in the project converges with the WQP historical records on industrial-water stress, but no matched neighboring-sector extraction was completed. - **Comparability:** low to medium. Historical and modern records overlap only for selected locations and variables. - **Known bias:** WQP coverage reflects agency monitoring design and reporting availability; the 1966 compilation reflects local authorship and civic-institutional framing. ### Missingness codes - `searched_no_result`: bounded WQP queries returned no rows outside the date ranges listed for the named sites. - `historical_measure_not_available`: no harmonized 1950–2000 nearshore/tributary water-quality series was assembled. - `geographic_match_uncertain`: point stations and the Dyer narrative do not equal the fixed `N05_E18` cell. - `period_match_uncertain`: the 1966 publication reports earlier events but is not a continuous time series. - `source_exists_not_accessible`: potentially relevant state, municipal, utility, port, census, and industrial records remain to be located and verified. - `not_searched`: no modern cell extraction for population, employment, industrial withdrawals, rail/port topology, or remediation was performed in this run. - `not_applicable`: a quadrant and composite score are not applicable until the formula and input completeness conditions are met. Reported zero values in source rows are retained as source observations and are not converted into absence, clean conditions, or zero scores. Archival or portal silence is not evidence of absence. ## Falsification and alternative explanations The evidence would weaken the working thesis if future work shows that: - the apparent water–industry relationship is explained as well or better by corporate and regulatory history without a distinctive sector constraint mechanism; - the result changes materially when the boundary is shifted from the regular grid cell to a watershed or industrial corridor without a principled crosswalk; - neighboring sectors with similar freshwater and transport access have different monitoring, industrial, or institutional trajectories under comparable conditions; - modern WQP and remediation records show that the historical pattern was isolated, mislocated, or driven by a different causal sequence; - documentation density is mistaken for adaptive capacity, especially where Indigenous, labor, or local records are missing. ## Next search path 1. Extract the WQP results for `USGS-05536356` by analyte, medium, unit, method, detection condition, and date; do not combine unlike rows. 2. Retrieve the WQP station/result records for additional Great Lakes pilot locations, including the Little Calumet and Grand Calumet sites already identified in the project, and map each point to the fixed cell with boundary uncertainty. 3. Independently verify the 1965 report’s industrial-water table and compare its analytes and sampling locations with the 1970/1980 WQP records. 4. Add Census decennial/ACS population and employment series and BLS QCEW or equivalent historical industry records, preserving county/place boundaries rather than treating them as cell values. 5. Search Archive.org and institutional repositories for 1800–1950 canal, rail, port, steel, utility, and municipal records, plus Indigenous-authored or primary records for the pre-industrial and colonial transition. 6. Keep `provisional_quadrant: unresolved` until the modern/historical variable crosswalk and pilot formula satisfy the SOP’s evidence conditions. ## Provenance register ### Modern structured sources 1. U.S. EPA, USGS, and National Water Quality Monitoring Council, **Water Quality Portal: Water Quality Data Download**, accessed 2026-08-06. The portal describes its cooperative data warehouse and download service. 2. Water Quality Portal, **WQP Web Services Guide**, accessed 2026-08-06. Used for the `siteid`, `mimeType=csv`, and result-query conventions. 3. Water Quality Portal station CSV, `USGS-04093200`, retrieved 2026-08-06. 4. Water Quality Portal result CSV, `USGS-04093200`, retrieved 2026-08-06. The selected records cited above are dated 1979-12-11, 1980-04-07, and 1980-04-08. 5. Water Quality Portal station CSV, `USGS-05536356`, retrieved 2026-08-06. 6. Water Quality Portal result CSV, `USGS-05536356`, retrieved 2026-08-06. Returned profile: 849 rows, 40 distinct dates, 2021-05-24 through 2024-02-22. 7. Water Quality Portal station CSV, `USGS-04092800`, retrieved 2026-08-06. 8. Water Quality Portal result CSV, `USGS-04092800`, retrieved 2026-08-06. Returned profile: 8 rows on 1970-10-13. ### Historical source 9. Lake County Public Library, **Reports And Papers Of Lake County Indiana (1958-1966)**, published/compiled 1966, Internet Archive identifier `reportsandpapersoflakecountyindiana`. Printed pages cited: 67–69, “History of Dyer,” by P. T. Gettler. The item metadata identifies it as a 210-page compilation of historical papers and reports from 1958 through 1966. Item: OCR derivative used as a locator: ### Related project source 10. U.S. Department of Health, Education, and Welfare, Public Health Service, Region V, **Report on pollution of the waters of the Grand Calumet River, Little Calumet River, Calumet River, Lake Michigan, Wolf Lake and their tributaries, Illinois-Indiana**, February 1965, Internet Archive identifier `water-pollution-rivers-images`. This prior project note remains the principal archival pollution report; the present note adds WQP monitoring records rather than duplicating its extraction. ## Record limits This note is a bounded research result, not a completed `N05_E18` sector audit. It adds monitoring coverage and historical institutional anchors, but establishes no final quadrant, no causal claim, no remediation score, and no global coverage. It preserves the next search path so the Great Lakes pilot can continue without treating heterogeneous point data as a complete cell record.