sweetapricity/bridgedeck-salt

Bridgedeck — Road Salt Exposure (USGS)

Part of the bridgedeck dataset collection for US bridge deck deterioration research.

Overview

State-level road salt (deicing salt) tier classification for all 50 US states + DC, derived from USGS estimates of road salt application across the conterminous United States.

Road salt is the strongest predictor of bridge deck deterioration in the bridgedeck XGBoost model (gain importance: salt_proportion=0.114, salt_tier=0.086), even as a static state-level proxy. Chloride from deicing salt penetrates concrete and accelerates rebar corrosion.

Source

Citation: Falcone, J.A., 2023. Estimates of Road Salt Application across the Conterminous United States, 1992–2019 (ver. 2.0, August 2023). USGS data release. https://doi.org/10.5066/P9MWBBF5

Downloaded from: USGS ScienceBase

Schema

One row per state (51 rows: 50 states + DC).

Column	Type	Description
state_code	str	2-digit FIPS state code (e.g. "48" = TX)
salt_tier	int	Tier 1=Heavy, 2=Moderate, 3=Minimal
salt_proportion	float	Relative salt use: 0.9 (heavy), 0.4 (moderate), 0.1 (minimal)

Tier Classification

Tier	Proportion	States
1 — Heavy	0.9	CT, DC, DE, IL, IN, MA, MD, ME, MI, MN, NH, NJ, NY, OH, PA, RI, VT, WI, WV
2 — Moderate	0.4	CO, IA, KS, KY, MO, MT, NE, NV, NM, ND, OK, OR, SD, TN, UT, WA, WY
3 — Minimal	0.1	AL, AR, AZ, CA, FL, GA, HI, ID, LA, MS, NC, SC, TX, VA

Join Key

Join to NBI bridge data on state_code (2-digit FIPS string).

Known Limitations

• Static — does not vary by year. Salt use has increased over time but the tier classification reflects the long-term average pattern (1992–2019).
• State-level — does not capture within-state variation (e.g., mountain counties in CO use more salt than desert counties).
• The full USGS release includes annual raster grids at 1 km resolution for 1992–2019 (230 MB). This simplified tier table is used here as a lightweight proxy.

Related Datasets

This dataset is part of the bridgedeck collection:

Repo	Description
sweetapricity/bridgedeck-nbi	National Bridge Inventory — structural features, 2000–2023
sweetapricity/bridgedeck-prism	PRISM climate features at bridge locations, 2000–2023
sweetapricity/bridgedeck-noaa	NOAA storm event counts by county, 2000–2023
sweetapricity/bridgedeck-nshm	USGS seismic hazard at bridge locations (static)
sweetapricity/bridgedeck-nfhl	FEMA flood zone classification at bridge locations (static)
sweetapricity/bridgedeck-salt	This dataset — USGS road salt tiers by state (static)

Paper

Ibrahim, A., Abdelkhalek, S., Zayed, T., Qureshi, A. H., & Mohammed Abdelkader, E. (2024). A comprehensive review of the key deterioration factors of concrete bridge decks. Buildings, 14(11), 3425.