Dataset Card for cafo-iowa

cafo-iowa is a dataset of Concentrated Animal Feeding Operations (CAFOs) in Iowa, compiled using NAIP satellite imagery, manual annotation, Iowa DNR permit records, and ReGrid parcel data. It provides facility-level estimates of animal populations derived from manually annotated barn footprints, enabling comparison against animals reported in state regulatory permits. The dataset was developed to study threshold gaming under the Clean Water Act, where operators may underreport animal unit counts to avoid federal permitting requirements.

Dataset Details

Dataset Description

cafo-iowa contains 6,525 Iowa wean-to-finish and grow-to-finish swine facilities with satellite-detected barns, matched to Iowa DNR permit records. Each facility includes both reported animal unit counts (from state permits) and estimated animal unit counts derived from manually annotated barn footprint area, enabling analysis of underreporting under Clean Water Act permitting rules. Compiled using NAIP 2021 aerial imagery, Iowa DNR Master Matrix permit data, and ReGrid parcel data. Permit addresses and parcel owner information are redacted; we will share unredacted versions of this data for research purposes upon request.

• Curated by: Helena Lyng-Olsen, Arun Frey, Evan Cook, Victoria Hollingshead, Elena Eneva, Daniel E. Ho (Stanford University)
• Funded by: Global Methane Hub; Doerr Sustainability Accelerator
• License: cafo-iowa © 2026 by Helena Lyng-Olsen, Arun Frey, Evan Cook, Victoria Hollingshead, Elena Eneva, and Daniel E. Ho is licensed under CC BY 4.0. If used in an academic work, please cite as:

Lyng-Olsen, Helena, Arun Frey, Evan Cook, Victoria Hollingshead, Elena Eneva, and Daniel E. Ho. "Hidden Herds: Satellite Evidence of Threshold Gaming Under the Clean Water Act." Submitted for review, 2026. Available at https://huggingface.co/datasets/reglab/cafo-iowa.

Dataset Sources

• Repository: https://huggingface.co/datasets/reglab/cafo-iowa
• Figshare: https://doi.org/10.6084/m9.figshare.32810540.v1
• Paper: Submitted for review.

Uses

Direct Use

• Analysis of regulatory compliance and threshold gaming under the Clean Water Act
• Environmental and public health research on CAFO emissions and pollution
• Comparison of self-reported versus satellite-estimated animal populations in Iowa
• Research on the spatial distribution of concentrated animal agriculture

Out-of-Scope Use

This dataset covers Iowa only and should not be generalized to other states without accounting for differences in permit structures, animal types, and regulatory regimes.

Dataset Contents

Files

File	Rows	Description
cafo_iowa_facilities_v1.csv	6,525	Main release table. One row per wean-to-finish or grow-to-finish swine facility with detected barns. See DATA_DICTIONARY.csv for column descriptions.
raw/*.csv	varies	Iowa DNR permit tables and supporting data as received, lightly processed for export.
processed/*.csv	varies	Derived tables used in analysis, including barn detections, facility-permit matches, and animal weight parameters.

Redacted Fields

The following fields are omitted from both raw/ and processed/ exports to protect privacy:

• permits.address — facility street address
• parcels.owner — parcel owner name
• parcels.address — parcel mailing address
• parcels.geometry — parcel boundary geometry

These fields are available for research purposes upon request.

Dataset Creation

Curation Rationale

Iowa has more CAFOs than any other state, and its permit system creates regulatory thresholds at 1,000 animal units (AU) that trigger federal Clean Water Act permitting requirements. This dataset was created to test whether operators strategically report animal counts just below these thresholds — and to quantify the gap between reported and actual animal populations using satellite evidence. The release table is scoped to wean-to-finish and grow-to-finish swine facilities, the facility types for which the satellite-based estimation methodology is most reliable.

Source Data

• NAIP 2021 aerial imagery (USDA National Agriculture Imagery Program, 0.6m resolution) — used to identify barn structures via manual annotation
• Iowa DNR Master Matrix permit data — animal unit counts, facility type, and waste management system for each permitted CAFO
• ReGrid parcel data — used to associate facilities with land ownership

Data Collection and Processing

Human annotators labeled barn structures in NAIP imagery across Iowa. Labeled barns were grouped into facilities and matched to state permit records using spatial proximity. Animal unit estimates were derived from barn footprint area using species-specific stocking density parameters. See methods_provenance.md for full methodological detail.

Personal and Sensitive Information

Facility locations are derived from public permit records. Permit addresses and parcel owner names are redacted in all exported files. The dataset does not include other personally identifiable information.

Citation

@misc{lyngolsen2026hiddenherds,
  title        = {Hidden Herds: Satellite Evidence of Threshold Gaming Under the Clean Water Act},
  author       = {Lyng-Olsen, Helena and Frey, Arun and Cook, Evan and Hollingshead, Victoria and Eneva, Elena and Ho, Daniel E.},
  year         = {2026},
  doi          = {10.6084/m9.figshare.32810540.v1},
  url          = {https://doi.org/10.6084/m9.figshare.32810540.v1},
  note         = {Submitted for review. Lead authors Helena Lyng-Olsen and Arun Frey contributed equally.}
}

Acknowledgements

The team would like to thank the Global Methane Hub and the Doerr Sustainability Accelerator for supporting this work.