Research Hub · Environmental justice behind bars

Prisons, people and hazards

Explore more than 4,000 U.S. prisons, jails and ICE detention centers: where they are, how many people they hold, how hot and humid it gets there and how that has changed since 1982, and, for state and federal prisons, exposure to flooding, wildfire, polluted air and toxic sites. Filter, compare, read the measures, and download what you find. Every number names its source.

Explore the mapFind and compare facilities Data & methodsDownloads, data dictionary, how to cite Document libraryRules, records, accounts; codebook and interview guide State heat rulesColorado beside seven other states Learn researchMethods and ethics in plain words Search everythingOne box, simple shortcuts System decoderCustody, release and parole terms Colorado studyHeat and cold inside, led with lived experience Priorities to policyAgency, legislature, ballot, courts Policy guideAll 14 Colorado measures, Nov 3

Facility explorer

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Measurelowhigh● prison · • jail · ◯ ICE · hollow = no data

Colors rank each place against the others. Lower 48 shown; Alaska and Hawaii are in the table.

–Facilities shown
–People held (reported)
–Prisons with a Superfund site within 5 km
–Median

Map shows the lower 48 states; Alaska and Hawaii facilities appear in the table. Prisons: hazard measures from Mothes & Hunt (2023), Colorado State University (HIFLD, June 2022). Heat history for prisons and jails: Tuholske et al. (2024), Nature Sustainability (HIFLD, 2020). ICE detention: UCLA Law COVID Behind Bars facility list. Some jail dots are placed approximately (within about 10 km); populations are as reported and dates vary. HIFLD's jail list is incomplete in some states.

Table

The prisons you filtered

Sort by any column. Click a row to see it on the map. Download gives you a spreadsheet of the current filter.

How to read the measures

What each number means

Each facility gets a raw value and a percentile: where it ranks among the facilities that have that measure (90 means more exposed than 90% of them). Hot humid days cover about 4,100 prisons and jails; the other measures cover the 1,865 state and federal prisons. Every percentile points the same way: higher means more exposed. For tree cover, that means less shade. Measures are calculated within the prison's boundary, often with a 1 km buffer. These are environmental measures of the place, not measured conditions inside buildings.

Topics

The questions behind the data

Short, sourced explainers for the issues the numbers can't show alone.

Siting

Built on cheap or contaminated land

  • A 2016 mapping for the Prison Ecology Project found 589 federal and state prisons within 3 miles of a Superfund cleanup site, and 134 within 1 mile. Truthout
  • In this hub's data, 130 of 1,865 prisons have a Superfund site within 5 km (about 3 miles); the method differs, so the counts differ. Mothes & Hunt 2023
  • Colorado: the Lincoln Park / Cotter Uranium Mill Superfund site, listed in 1984, sits about 2 miles south of Cañon City. Contaminants include uranium, molybdenum and TCE. CDPHE
Siting

Far from town, by design

  • Before 1980, 36% of prisons were rural. In the 1990s, 245 prisons opened in rural America, about one every 15 days. Huling 2002, via Prison Policy Initiative
  • U.S. prisons grew from 511 in 1970 to 1,663 in 2000, mostly in rural places, often sought by towns in economic decline. Eason, Big House on the Prairie
  • In 2008, Fremont County, Colorado held 12 state and federal facilities; county officials said half of local jobs were tied to corrections. Colorado Independent
Infrastructure

Air conditioning vs. a swamp cooler

  • See it move: Air & Temperature, an interactive cutaway shows how air reaches the dayroom and the cells under each system, summer and winter.
  • Air conditioning moves heat outside through a refrigerant loop, and dries the air as moisture condenses on the cold coil. Archtoolbox
  • An evaporative (swamp) cooler blows outside air through wet pads. It cools by adding moisture, so it works worse as humidity rises. U.S. DOE
  • Example: at 100°F and 10% humidity, the air comes out near 73°F; at 95°F and 50% humidity, only near 84°F. PNNL
  • In 2023, a writer at Fremont Correctional Facility reported swamp coolers and south-tier cells usually above 90°F. Where Colorado prisons have AC, it is often switched on by calendar date, not by the heat. Prison Journalism Project · CPR
Policy

The rule on paper in Colorado

  • State health rules for penal institutions require indoor temperatures of at least 61°F in the coldest months and below 86°F in the warmest months (6 CCR 1010-13, section 9.4). Colorado Code of Regulations
  • The rule is set by the Colorado Department of Public Health and Environment, not the Department of Corrections.
  • Buildings that opened before the rule can be “deemed acceptable if in good repair,” and a prison can ask for a variance. 6 CCR 1010-13 §1.2
  • Since 2020 the health department must inspect prisons every year, immigration detention included. No public inspection reports on CDOC prisons were found. HB20-1409
  • Compare: How states handle heat, and where Colorado stands sets Colorado beside California, New Mexico, Georgia, Texas, Louisiana, Virginia and Iowa.
Infrastructure

Old buildings, deferred repairs

  • The average Colorado corrections building is 51 years old; 5 of 19 facilities were built before 1960. The department says it needs $19.0M a year for maintenance; it got $5.8M in FY23-24. JBC staff briefing
  • The state's 5-year repair plan lists HVAC, chiller or boiler work at nine prisons, including “Replace Chillers 1 & 3” at Limon. Office of the State Architect
  • A 2022 request said Sterling's kitchen “has no air conditioning.” CDOC capital request
  • The Colorado page lists the repair items and a record of emergencies.
Climate

A warming Colorado

  • Colorado has warmed about 2.5°F since the early 1900s; very hot days have been above average since 2000. NOAA State Climate Summary
  • Another 2.5–5.0°F of warming is projected by 2050. Climate Change in Colorado, 2024
  • Daily temperature records for prison towns are free through NOAA's ACIS: Cañon City (051294), Limon (055018), Buena Vista 2S (051071), Pueblo Airport (056740), Las Animas (054834), Trinidad (058429). SC-ACIS
Policy

Rules that limit coping

  • Fans sold through the prison store cost $29.66 in 2023, with waits of 3 to 7 weeks; at 86¢ a day in state pay, that is about two months of wages. Prison Journalism Project
  • Clothing rules limit how people can dress for heat: “I can only get so naked before it lands me in segregation.” (same source)
  • Covering a vent against wildfire smoke can bring an infraction, sometimes solitary confinement. CPR, 2025
  • CDOC's Extreme Weather rule (2025) covers outdoor work and recreation: an alert at a 105°F heat index stops strenuous outdoor activity. It sets no temperature for housing units. AR 850-17
  • One fan is allowed in general population, but not in restrictive housing, where property “may be limited, or removed altogether.” Thermal shirts and pants are allowed. AR 850-06
  • Grievances must be filed within 30 days, one problem each, on a single form; a procedural denial means the person has not exhausted and cannot yet sue. AR 850-04
  • Some people feared punishment for complaining about conditions. CU Boulder Today, 2024
National context

Heat and health: the national picture

  • These findings come from Texas and national research. Colorado's case rests on documented conditions, exposure and the state's own 61–86°F standard.
  • In Texas prisons without air conditioning, about 13% of warm-month deaths from 2001 to 2019 (271 deaths) were tied to extreme heat. Each degree above 85°F raised the daily risk of death by 0.7%. Skarha et al., 2022
  • Researchers estimated daily heat exposure for 4,078 U.S. prisons from 1982 to 2020, and published the data openly. Tuholske et al., Nature Sustainability, 2024
Colorado research

What Colorado studies found

  • A GIS assessment of 110 Colorado facilities found 74.5%, holding 83% of incarcerated people, faced moderate or high exposure to at least one hazard; about half faced extreme heat risk. Dashti et al., 2023
  • Interviews with 35 formerly incarcerated Coloradans found 65% had lived through extreme temperatures, wildfire or flooding inside. Barron et al., 2024
  • CIRCol, the Climate and Incarceration Research Collective at CU Boulder, does community-based participatory research on these harms. CIRCol
Methods

Research with people who lived it

  • A CU Anschutz–CU Boulder team, funded by an AB Nexus grant in 2024, is studying extreme health risks at the nexus of climate change, incarceration and reentry in Colorado. AB Nexus 2024 awards
  • Their DRS2026 paper pairs interviews and focus groups with participatory drawing of the spaces where extreme temperatures hit hardest. Langdon-Dimidjian et al., DRS2026
  • A related model: Forensic Architecture and Amnesty International built 3D models of a prison from survivors' descriptions, which survivors then corrected. Amnesty, Saydnaya

Coming next · Spaces of exposure

Findings from community research using a forensic vulnerability model: formerly incarcerated participants drew the places where heat and cold hit hardest, and an architect turned the drawings into renderings. Publicly presented materials will appear here, credited to the study team and advisory boards.

Work areas · sewing shopKitchenCellsSolitary confinementThe yard

Data library

Where the data comes from

Who can use each source: Open anyone, no sign-up · Free sign-up or terms of use · Agreement restricted, needs a data use agreement · .

SourceWhat it gives youAccessCovers

Cite

Using this in your work

Cite the original data. The hazard measures come from:

Mothes, C., & Hunt, D. (2023). Mapping environmental injustices within the U.S. prison system (Version v2023-1). Colorado State University. Zenodo. https://doi.org/10.5281/zenodo.8306856

Facility boundaries: U.S. Department of Homeland Security, Homeland Infrastructure Foundation-Level Data (HIFLD), Prison Boundaries (June 2022 update), as used in the dataset above.

Heat history (hot humid days):

Tuholske, C., Lynch, V. D., Spriggs, R., Ahn, Y., Raymond, C., Nigra, A. E., & Parks, R. M. (2024). Hazardous heat exposure among incarcerated people in the United States. Nature Sustainability. https://doi.org/10.1038/s41893-024-01293-y