sweetapricity/bridgedeck-statsgo

Bridgedeck — STATSGO Soil Properties

Soil properties at ~906k US bridge locations, queried from the NRCS Soil Data Access (SDA) REST API using the STATSGO2/SSURGO national database.

Source

• Database: NRCS Soil Data Access (SDA) — https://SDMDataAccess.sc.egov.usda.gov
• Spatial data: STATSGO2 / SSURGO national map units
• Query method: Point-in-polygon via SDA_Get_Mukey_from_intersection_with_WktWgs84
• Coverage: All unique NBI bridge locations in CONUS (~906k points)

Schema

Column	Type	Description
bridge_id	str	Bridge identifier ({state}_{county}_{structure})
latitude	float	Bridge latitude (WGS-84)
longitude	float	Bridge longitude (WGS-84)
mukey	str	STATSGO/SSURGO map unit key
compname	str	Dominant soil component name
comppct_r	int	Component percentage of map unit
corsteel	str	Corrosion potential for steel (High/Moderate/Low)
corcon	str	Corrosion potential for concrete (High/Moderate/Low)
drainagecl	str	Drainage class (Well drained / Somewhat poorly drained / etc.)
hydgrp	str	Hydrologic group (A/B/C/D) — relates to water retention
taxorder	str	Soil taxonomy order (Mollisols, Alfisols, etc.)
silttotal_r	float	Surface horizon silt percentage (%) — >50% indicates frost susceptibility

Derived Features

The ETL script (statsgo_clean.py) derives:

• soil_type: Frost susceptibility classification based on silt content and hydrologic group

Notes

• Urban bridges (~30%) return empty soil data ("Urban land" has no soil properties)
• These receive NaN in the derived features — XGBoost handles NaN natively
• Data is static (soil properties don't change year to year)

Related Datasets

• bridgedeck-nbi — bridge locations used for spatial query
• bridgedeck-elevation — complementary physical property

Citation

USDA-NRCS. Soil Survey Staff. Web Soil Survey. https://websoilsurvey.sc.egov.usda.gov/