What This Is
A serverless browser-based property analysis tool for South-Central Montana covering Yellowstone, Carbon, Stillwater, Musselshell, Treasure, and Big Horn counties. Search any address to retrieve parcel data, assess environmental risk, estimate commute time, and evaluate soil conditions.
Data Sources
Parcel DataMontana State Library — Montana Cadastral dataset. Uploaded as Mapbox vector tilesets.
Address SearchMapbox Geocoding API, filtered to address-level results, biased to South-Central Montana.
Drive TimeMapbox Directions API (driving profile) to St. Vincent's Healthcare at -108.5258, 45.7952.
Winter CommuteSpeed reduction factors applied to normal drive time: highway 72%, county road 60%, local 45%, unpaved/private 48%.
Federal SuperfundHardcoded from EPA CERCLIS/SEMS as of 2024. 5 federal NPL sites in or near the region. Site centroids shown — no polygon boundaries displayed (would require official EPA SEGS data).
State SuperfundHardcoded from Montana DEQ CECRA Priority List (2024). 11 state-listed sites across the six-county region.
Soil DataUSDA NRCS SSURGO via Esri Living Atlas feature services. Queries dominant soil component at parcel centroid.
Property Tax EstimateMontana DOR taxable value ratios by class × approximate 2023 county mill levies. Not a substitute for official tax records.
Quality of LifeOpenStreetMap via Overpass API. No API key required. Coverage varies by area.
How Variables Are Calculated
Superfund Tier 1Parcel bounding box tested for intersection with known site coordinates.
Superfund Tier 2Haversine distance from parcel centroid. Sites within 500 m trigger Tier 2.
Superfund Tier 3Closest federal and state site within 25 miles shown with straight-line distance.
Soil Shrink-SwellDerived from SSURGO hydrologic group: D = High, C = Moderate, A/B = Low. Vertic subgroups = Very High.
Foundation Risk ScoreComposite: shrink-swell (0–3) + drainage index (0–2) + flood frequency (0–3). ≥4 = High, ≥2 = Moderate.
Tax EstimateTotal assessed value × DOR taxable value ratio × county mill levy ÷ 1000. Not available for productivity-based classes.
Limitations & Disclaimers
For informational purposes only. Not a substitute for a licensed property inspection, Phase I/II ESA, geotechnical report, title search, or legal advice. Parcel data may lag one tax cycle. Soil data reflects dominant conditions at parcel centroid only. Tax estimates are approximations. Always verify with county assessor and treasurer before financial decisions.
Technology Stack
Static HTML/CSS/JS on Cloudflare Pages. Mapbox GL JS v3.3. Vector tilesets in Mapbox Studio. No backend. All computation runs in-browser.