How this was built

Distance verdict: Every report opens with a separate distance check. CLEAR means the address is at least 2.5 miles from every one of our 104 mapped courses using their available boundaries; NOT CLEAR names the nearest course and its distance. The 2.5-mile threshold is an Initiative editorial choice, not a scientifically established safe radius, and it is less restrictive than the 3-mile school clearance radius. The verdict is a distance check only and is kept separate from the score below.

We start each home at 100 points, subtracts the deductions below and limits the result to 0 through 100. Distance, the CLEAR verdict and the additional-course deduction use the nearest of our 104 listed golf courses, measured between the closest mapped boundary points. Slope, wind and drainage are judged against every course within 3 miles, and each of those three deductions is charged once for the worst case found, never once per course.

Score band labels: 90 to 100: Pristine Grounds; 75 to 89: High Ground; 50 to 74: Watch the Wind; 0 to 49: Downstream. These are Initiative screening labels, not certified environmental ratings.

Inputs and sources

• Address and distance: OpenStreetMap Nominatim geocodes the entered address. We attempt an address-matched home parcel lookup through Westchester County GIS and Connecticut municipal parcels aggregated by the state. The shortest straight-line separation between mapped property boundaries determines the nearest course and distance verdict. Failed or ambiguous home parcel lookups use the geocoded address point, disclosed per report. Both tools share one dated course-boundary dataset. County/municipal parcels are preferred; OpenStreetMap golf-course polygons are a documented fallback where obtainable, not surveyed legal property lines. Where neither is verified, a course address point remains approximate. The current Overpass attempts were unavailable. Each course lists its actual source. Parcels can include non-golf land and the assembled extent may be incomplete.
• Elevation: USGS Elevation Point Query Service queries the closest home parcel-edge point (or address point fallback) and the closest boundary point of every course checked within 3 miles. A home lower than any checked course loses 15 points once, whatever the number of courses involved; ground equal to or higher than every checked course subtracts zero. Missing elevation at the nearest course prevents a complete score. Elevation alone cannot establish surface drainage or groundwater connectivity.
• Wind: Bearing is measured from the closest course boundary point to the closest home boundary point or address-point fallback. The fixed west-northwest assumption, not a site-specific study or live weather, treats 67.5° through 157.5° as downwind (-10), 247.5° through 337.5° as upwind (0), and other bearings as crosswind (0). Coincident points at the nearest course have no direction and no complete score. Bearings are measured for every checked course, and a home downwind of any of them loses 10 points once. NOAA/NCEI station observations are the wind-data source, not verification of our fixed direction; historical Bridgeport winds vary and do not substantiate constant west-northwest winds.
• Surface water: USGS NHDPlusV2 hydrography and NLDI directed flowlines determine catchment ordering after polygon membership is independently validated at both measurement points. Home downstream of any checked course subtracts 10, charged once; upstream or “Not determined” against every checked course subtracts zero. Shared catchments, missing data, request limits and ambiguous connections within a 100-kilometre search remain unresolved. No drainage is guessed from elevation, and catchment connectivity does not prove runoff passes through the property or a groundwater connection.
• Nearby courses and races: Every mapped course within 3 miles is listed nearest first with its edge-distance estimate and a count. The CLEAR / NOT CLEAR verdict uses only the nearest course. For the score, each additional course within 3 miles beyond the nearest one deducts 5 points, up to a maximum deduction of 20 points for additional courses. Slope, wind and drainage are evaluated for every course in that list, and each of the three deductions is charged once for the worst case found; the report names the course that established each one. Active races cover the home town and every listed course town using the shared sourced town registry and supplied candidate dataset. All supplied candidates are listed neutrally for Tuesday, November 3, 2026. Districts may split towns: this is a town-level approximation, not your ballot; confirm with your county board of elections or Connecticut town registrar. Out-of-state course-town officials do not establish voting eligibility.
• General aviation airports: We keep a dated registry of general aviation airports in the project footprint that sell leaded avgas (100LL) and host piston-engine traffic, including Westchester County (HPN), Danbury Municipal (DXR), Sikorsky Memorial (BDR) and Waterbury-Oxford (OXC). Only the nearest such airport deducts points, once: under 0.5 miles deducts 15, 0.5 to under 1 mile deducts 10, 1 through 2 miles deducts 5, and beyond 2 miles deducts zero. Airport distances use airport reference points because airport property boundaries are not yet in our boundary dataset; they are approximate and disclosed. The deduction reflects proximity to piston-engine traffic burning leaded fuel (100LL), based on the 2021 Reid-Hillview Airport study in Santa Clara County, published peer-reviewed as Zahran, Keyes and Lanphear, PNAS Nexus, January 2023, which found elevated blood lead in children within about half a mile of a general aviation airport, with effects studied out to roughly a mile. Proximity is a reason to test and ask, not proof of contamination or harm.
• Water: You select private well, municipal supply or I do not know, and may report a well depth. We do not obtain well tests, utility test results or evidence of contamination for this calculation. Municipal supply and unknown sources lose no points, but that does not establish pesticide-free water; an unknown source is an open question, not an assurance.

The weights and rating cutoffs are Initiative editorial screening rules, not a formula derived from a scientific study. No pesticide concentrations, application quantities, air samples or health outcomes are measured. Straight-line edge distance is not a surveyed measurement. Parcel and geocoding data change over time. “Not determined” is an open question, not an assurance. This is a screening estimate, not a professional environmental assessment; no rating proves safety or contamination.

School-owned disclosure and parent reports: Reports describe the school’s own disclosures separately from nearby course information. Parents record how many of four categories were supplied: pesticide inventory, dated application records, parent notification policy and monitoring results. All four is shown as GREEN, partial categories as YELLOW, and none as RED with “No information,” always labeled parent-submitted and unverified. Historical selections are preserved privately; they are not averaged into an official school rating or used to set the course-information color.

Courses within 3 miles: Each school lists every mapped golf course within 3 miles, nearest first, with the shortest straight-line distance between available property boundaries, using GIS parcels or documented OpenStreetMap polygons where obtainable. Unavailable school boundaries use the supplied address point; unavailable course boundaries use a disclosed approximate point fallback. The list is a location record only; it does not show chemical use or exposure. Active races cover the school’s town plus the town of every listed course.

School site score: 0 to 100

A separate site score starts at 100, subtracts the factors below and is limited to 0 through 100. Distance uses the nearest mapped course by boundary separation. Slope, wind and drainage are judged against every mapped course within 3 miles, consistent with the home Ground Report, and each of those three deductions is charged once for the worst case found, never once per course. In addition, each additional course within 3 miles beyond the nearest one deducts 5 points, up to a maximum deduction of 20 points for additional courses. It uses the same closest-edge distance as the school table. The unchanged final site score supplies the proximity color; reviewed course information can worsen the displayed rating without changing that score.

• Elevation: Elevations at the closest school and course boundary points (or disclosed point fallbacks) in feet are batch-queried from USGS EPQS and dated in the school breakdown. Ground lower than any checked course within 3 miles loses 15 points once, whatever the number of courses involved. Unavailable elevation at the nearest course receives no complete score, rather than an invented value. Relative elevation alone does not determine drainage.
• Wind: We use the same fixed west-northwest assumption as the home report. Bearings from the closest course boundary point to the closest school boundary point or address fallback of 67.5° through 157.5° inclusive are treated as downwind; 247.5° through 337.5° are upwind, and other bearings are crosswind. NOAA/NCEI Integrated Surface Database supplies station wind observations for regional wind roses, including Westchester County Airport (HPN) and Bridgeport/Sikorsky (BDR). No station wind rose was calculated for these scores. NOAA’s historical climatic wind table reports Bridgeport’s annual direction as west-southwest, with seasonal variation, not west-northwest. It does not establish modern Westchester conditions. The fixed direction and sector are therefore our assumptions for consistency with the home report, not a verified regional prevailing direction, site-specific study, live wind or measured spray path. NOAA wind-rose guidance explains station-based direction frequencies.
• General aviation airports: The school site score uses the same dated registry of general aviation airports that sell leaded avgas (100LL) and host piston-engine traffic as the home Ground Report, including Westchester County (HPN), Danbury Municipal (DXR), Sikorsky Memorial (BDR) and Waterbury-Oxford (OXC). Only the nearest such airport deducts points, once: under 0.5 miles deducts 15, 0.5 to under 1 mile deducts 10, 1 through 2 miles deducts 5, and beyond 2 miles deducts zero. Other such airports within 2 miles are listed on the school page for context. Airport distances use airport reference points because airport property boundaries are not yet in our boundary dataset; they are approximate and disclosed. The deduction reflects proximity to piston-engine traffic burning leaded fuel (100LL), based on the 2021 Reid-Hillview Airport study in Santa Clara County, published peer-reviewed as Zahran, Keyes and Lanphear, PNAS Nexus, January 2023, which found elevated blood lead in children within about half a mile of a general aviation airport, with effects studied out to roughly a mile. Proximity is a reason to test and ask, not proof of contamination or harm.
• Surface water: USGS NHDPlusV2 catchment polygons are checked by point-in-polygon against the closest school and course measurement coordinates. Connected flowlines are requested through the USGS Network Linked Data Index, using downstream branches (DD) and upstream tributaries (UT), up to 100 kilometres. A downstream deduction requires both points to have a single validated catchment and the school catchment to occur on a connected downstream branch from the course catchment. Reverse connectivity establishes upstream. Shared catchments, absent connections within the search extent, unavailable responses and ambiguous membership remain “Not determined.” The October 19, 2026 batch established 50 downstream and 8 upstream catchment relationships; 600 remain not determined, including shared catchments and unavailable or ambiguous data, and receive no deduction. The October 21, 2026 pathway batch repeats this test for every course within 3 miles of a school, so a downstream deduction applies when any checked course drains toward the school, charged once. Catchment connectivity alone would not prove that runoff passes through a school campus or a groundwater connection; storm drains and local diversions may not be represented.

Inputs and sources

• Locations and distances: Schools use shortest straight-line property-line to property-line distance between available boundary geometries. Sources: Westchester County GIS tax parcels and Connecticut municipal GIS parcels. OpenStreetMap golf outlines are a documented fallback, not legal property lines; current Overpass attempts were unavailable, so unverified courses remain points. Boundary sources and dates are recorded per property (obtained October 19, 2026). School address points and course point fallbacks are disclosed and approximate. Property extents may include non-school/non-golf land or omit unverified parcels. Straight-line edge distance is not a surveyed measurement; parcel data changes over time, and distance alone does not measure exposure.
• Pathway evidence: Slope, wind and drainage for each school and course pair inside 3 miles are held in a dated evidence file built from USGS EPQS elevations, NHDPlus catchment polygons and NLDI directed flowlines, with the measurement coordinates recorded for every pair. A pair whose evidence cannot be established contributes nothing rather than a guess, and evidence is only used while the recorded coordinates still match the current boundary measurement. The school page names the course that established each deduction.
• Enrollment: The site lists NCES 2024-25 for public schools and school directories for private schools; preschool counts are estimates. Enrollment does not affect any rating.
• Research context: Krzyzanowski et al., 2025, JAMA Network Open study of golf-course proximity and Parkinson disease informs the site’s three-mile focus. It does not validate these color bands, establish toxicity at a school or measure harm to children.
• Disclosure evidence: A school’s own documents or responses, with the source and response date supplied in each parent report. No completed independent school disclosure reviews are currently recorded.

The weights and cutoffs are Initiative editorial screening rules, not a scientific formula. “Not determined” is an open question, not an assurance, and receives no surface-water deduction. No pesticide measurements are taken. The proximity color derives from the site score, which considers distance, additional courses, sourced elevation, assumed wind, mapped surface drainage and the nearest leaded-avgas airport. The final rating also considers reviewed course information. Transparency measures disclosure, not chemical safety. No score or rating proves safety or contamination.