Most of Blackwater was built recently: 7% of its homes predate 1940 and the median home dates from 2002. Below: maps from 1907 on and the census since 1990.
Founding year: the first Blackwater post office (Blevins & Helbock, CC0).
History grade
What drives Blackwater’s History grade
On its age, its old homes and the National Register, Blackwater is more historic than 15% of U.S. towns. Its share of homes from before 1940 holds the grade up; its age pulls it down.
D
HistoryA character grade: shown, never part of Blackwater’s overall grade.
Few Arizona towns list much on the Register (a typical Arizona town has 0.1 per 10,000 residents, the U.S. 2.4), so Blackwater’s 0.0 sits below most of its state (29% of Arizona towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
How sure. Graded on any two of the three inputs instead, the letter would range from D to C−. The pre-1940 share is a Census survey estimate (±11.6 points). The founding year is the first post office, not a stated founding date.
Founding year: the first post office (other dates in Quick answers). Homes: Census ACS 2020–24. National Register: National Park Service, May 2026 list; each listing counted once (boundary changes and added documentation belong to their listing), and a historic district counts its contributing buildings. How TownRatings grades history →
What stands out about Blackwater’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
Every edition of the U.S. Geological Survey’s map of Blackwater. Tap a year, or press play to watch the town change.
1907Sacaton sheet · 1:62,500
U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of Blackwater.
The story so far
Blackwater, in brief
Wikipedia doesn’t have a history of Blackwater yet. The photos, dates and memories neighbors add here are how it gets written.
Blackwater is a native village and census-designated place (CDP) on the Gila River Reservation in Pinal County, Arizona, United States. The population was 1,062 at the 2010 census, up from 504 in 2000.
Its first post office opened in 1907. Between the 2010 and 2020 censuses its population grew from 1,062 to 1,190 (+12%).
Intro from Wikipedia. Population: U.S. Census Bureau.
Timeline
Blackwater, 1907 to 1931
Woven from the archive, old maps, post office records, the National Register and the people born here.
The Blackwater post office opened in 1907, the earliest record of the town by name (U.S. post office records).
How does Blackwater rank for history?
Blackwater is more historic than 15% of U.S. towns. The History grade combines the town’s founding era, the share of homes built before 1940 and its National Register listings. It’s a character grade, so it isn’t part of the overall grade. How it works.
How old are the homes in Blackwater?
7% of Blackwater’s homes were built before 1940 (Census estimate, ±11.6 points), against a typical 0.4% for an Arizona town; the median home was built in 2002.
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021).
From U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia), the US Post Offices dataset (Blevins & Helbock) and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
