42,498 people (2024 Census estimate, −3.4% since 2020)
6,279 square miles of land · 7 people per square mile
“Highest” and “lowest” are just order, not grades: a high rank for poverty or hazard losses means more of it. Each figure's source is in its section below.
32 active community water systems list Siskiyou County in the area they serve, reporting 28,539 people served in all (a system that crosses county lines counts its whole population).
| YREKA, CITY OF surface water · local government · CA4710011 | 7,879 served |
| MT. SHASTA, CITY OF groundwater · local government · CA4710008 | 3,642 served |
| LAKE SHASTINA C.S.D groundwater · private · CA4710013 | 2,790 served |
| WEED, CITY OF groundwater · local government · CA4710009 | 2,662 served |
| DUNSMUIR, CITY OF groundwater · local government · CA4710002 | 1,707 served |
| MCCLOUD C.S.D. groundwater · local government · CA4710006 | 1,317 served |
| MONTAGUE, CITY OF surface water · local government · CA4710007 | 1,264 served |
| HAPPY CAMP C.S.D. surface water · local government · CA4710012 | 1,100 served |
Source: U.S. EPA Safe Drinking Water Information System (SDWIS), active community systems, . Look up any system's violations and test results with EPA's search using its ID.
About 109 people were held in Siskiyou County's jail, in Vera's latest figure (2025). In 2020 it was about 79.
Source: Vera Institute of Justice, Incarceration Trends (built from federal Bureau of Justice Statistics jail surveys). Counties without their own jail, or that share one, may show no figure.
26 school districts have their office in Siskiyou County. School taxes are usually the largest part of a property tax bill.
Spent $18.7 million — $16.5 million to run schools, about $18,593 per student, plus $1.7 million on buildings and equipment. Money in: $3.6 million local (mostly property tax), $12.8 million state, $2.8 million federal.
Spent $14.9 million — $12.7 million to run schools, about $17,385 per student, plus $1.3 million on buildings and equipment. Money in: $5.9 million local (mostly property tax), $9.2 million state, $1.7 million federal. Long-term debt: $7.6 million.
Spent $14.2 million — $12.1 million to run schools, about $19,481 per student, plus $1.7 million on buildings and equipment. Money in: $3.1 million local (mostly property tax), $8.3 million state, $2 million federal.
Spent $10.6 million — $9.7 million to run schools, about $18,322 per student, plus $622,000 on buildings and equipment. Money in: $5.5 million local (mostly property tax), $5.5 million state, $973,000 federal. Long-term debt: $15.5 million.
Spent $7.5 million — $7.2 million to run schools, about $15,540 per student, plus $163,000 on buildings and equipment. Money in: $2.9 million local (mostly property tax), $4.5 million state, $1.1 million federal. Long-term debt: $225,000.
Spent $9.6 million — $7.9 million to run schools, about $19,165 per student, plus $1.6 million on buildings and equipment. Money in: $2.2 million local (mostly property tax), $6.8 million state, $2.3 million federal.
Spent $14.9 million — $6.6 million to run schools, about $20,291 per student, plus $8.2 million on buildings and equipment. Money in: $2.5 million local (mostly property tax), $21.9 million state, $638,000 federal.
Spent $5.9 million — $5.7 million to run schools, about $20,401 per student, plus $85,000 on buildings and equipment. Money in: $1.6 million local (mostly property tax), $4.9 million state, $772,000 federal.
And 18 more.
Source: U.S. Census Bureau, 2023 Annual Survey of School System Finances. Districts are listed by the county of their main office; some serve neighboring counties too.
Source: County Health Rankings & Roadmaps 2025 (University of Wisconsin Population Health Institute), which gathers federal data (CDC, Census, and others); measures cover different recent years. Blank lines aren't reported for small counties.
Overall risk: Relatively Moderate compared with other U.S. counties. FEMA estimates natural hazards cost Siskiyou County about $57 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Relatively Moderate; social vulnerability: Relatively High.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
425 bridges in Siskiyou County: 170 in good condition, 230 fair, and 25 poor (5.9%). “Poor” means a main part — the deck, the beams, or the supports — is rated 4 or lower on the federal 0–9 scale. It doesn't mean unsafe to drive; unsafe bridges are closed.
| INTERSTATE 5 over PANORAMA ROAD · built 1960 | 18,000 vehicles a day |
| STATE ROUTE 96 over THOMPSON CREEK · built 1952 | 615 vehicles a day |
| STATE ROUTE 96 over SCOTT RIVER · built 1957 | 600 vehicles a day |
| N OLD STAGE RD over SHASTA RIVER · built 1968 | 379 vehicles a day |
| LAKE VIEW ROAD over KLAMATH RIVER · built 1960 | 226 vehicles a day |
| SALMON RIVER ROAD over SALMON RIVER · built 1966 | 210 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $38.9 million of work in Siskiyou County in fiscal 2025, about $882 per resident — to the county, cities, schools, hospitals, nonprofits and others.
Source: USAspending.gov, grants by place of performance, fiscal 2025 (Oct. 2024 to Sept. 2025). Search it by county to see each award.
From Grants.gov: posted grants listing county governments as eligible, soonest deadline first; research-only and overseas programs left out; list updated 2026-10-13, refreshed weekly. 62 are open in all. Cities, towns, school districts and nonprofits have their own lists there.
General election: Tuesday, November 3, 2026. Ballots mailed; drop boxes open: 2026-10-05. Last day to register to vote: 2026-10-19. Early in-person voting: 2026-10-24 to 2026-11-03. Election Day: 2026-11-03. Last day for mailed ballots to arrive: 2026-11-10.
Source: California Secretary of State — Nov. 3, 2026 key dates · California Official Voter Information Guide — dates to remember · California Secretary of State — make a plan to vote
The budget, property tax rates, audits, local officials and offices for Siskiyou County come from the county's own records, which we haven't gathered — not gathered, never hidden. See what a full county site looks like, or ask to have Siskiyou County built: brayden.ozark@gmail.com.
More of California: the state government and every county in California.
Nearby counties: Jackson County, OR (57 mi) · Shasta County (62 mi) · Trinity County (71 mi) · Del Norte County (76 mi) · Josephine County, OR (77 mi) · Klamath County, OR (88 mi).