75,129 people (2024 Census estimate, +5.5% since 2020)
3,458 square miles of land · 22 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.
56 active community water systems list Lewis and Clark County in the area they serve, reporting 47,271 people served in all (a system that crosses county lines counts its whole population).
| HELENA WATER SYSTEM surface water · local government · MT0000241 | 32,091 served |
| EAST HELENA CITY OF groundwater · local government · MT0000196 | 2,114 served |
| EASTGATE VILLAGE SEWER AND WATER groundwater · private · MT0001784 | 2,000 served |
| VA MEDICAL CENTER HELENA buys surface water · federal · MT0000246 | 1,275 served |
| HELENA LEISURE LLC groundwater · private · MT0000590 | 1,200 served |
| TEN MILE AND PLEASANT VALLEY WUA groundwater · private · MT0002005 | 750 served |
| NORTH STAR PUD groundwater · private · MT0004264 | 715 served |
| MCHUGH MOBILE HOME PARK groundwater · private · MT0002917 | 490 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 154 people were held in Lewis and Clark County's jail, in Vera's latest figure (2023), or 332 per 100,000 residents ages 15–64. In 2018 it was about 116.
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.
9 school districts have their office in Lewis and Clark County. School taxes are usually the largest part of a property tax bill.
Spent $76.1 million — $71.9 million to run schools, about $13,752 per student, plus $1.4 million on buildings and equipment. Money in: $36.1 million local (mostly property tax), $30.6 million state, $11.5 million federal. Long-term debt: $58.8 million.
Spent $34.4 million — $32.8 million to run schools, about $13,044 per student, plus $832,000 on buildings and equipment. Money in: $16.7 million local (mostly property tax), $16 million state, $1.9 million federal. Long-term debt: $203,000.
Spent $21.8 million — $19.5 million to run schools, about $10,003 per student, plus $273,000 on buildings and equipment. Money in: $9.6 million local (mostly property tax), $11.8 million state, $2.8 million federal. Long-term debt: $43.7 million.
Spent $2.8 million — $2.7 million to run schools, about $18,141 per student, plus $53,000 on buildings and equipment. Money in: $792,000 local (mostly property tax), $1.2 million state, $839,000 federal. Long-term debt: $4,000.
Spent $1.2 million — $1.1 million to run schools, about $11,944 per student, plus $144,000 on buildings and equipment. Money in: $498,000 local (mostly property tax), $512,000 state, $285,000 federal. Long-term debt: $6,000.
Spent $1.6 million — $564,000 to run schools, about $14,842 per student, plus $834,000 on buildings and equipment. Money in: $630,000 local (mostly property tax), $156,000 state, $295,000 federal.
Spent $972,000 — $918,000 to run schools, about $38,250 per student. Money in: $675,000 local (mostly property tax), $386,000 state, $72,000 federal. Long-term debt: $158,000.
Spent $192,000 — $192,000 to run schools, about $14,769 per student. Money in: $27,000 local (mostly property tax), $106,000 state, $85,000 federal.
And 1 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 Low compared with other U.S. counties. FEMA estimates natural hazards cost Lewis and Clark County about $34.8 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very High; social vulnerability: Relatively Low.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
204 bridges in Lewis and Clark County: 118 in good condition, 75 fair, and 11 poor (5.4%). “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.
| LINCOLN RD over INT LINCOLN-I 15 · built 1962 | 7,492 vehicles a day |
| FRONTAGE ROAD 295 over TEN MILE CREEK 071 · built 1962 | 1,929 vehicles a day |
| S CRUSE AVE over PEDESTRIAN UNDERPASS · built 1972 | 1,548 vehicles a day |
| S 200 over STOCKPASS · built 1949 | 1,432 vehicles a day |
| CRAIG FRONTAGE RD over MISSOURI RIVER 054 · built 1933 | 484 vehicles a day |
| LOVERS LANE over ELK CREEK 041 · built 1914 | 100 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $1.1 billion of work in Lewis and Clark County in fiscal 2025, about $15,153 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.
Registration deadlines, early voting and polling places for Montana are on the federal site vote.gov, which links to the state's official election office.
The budget, property tax rates, audits, local officials and offices for Lewis and Clark 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 Lewis and Clark County built: brayden.ozark@gmail.com.
More of Montana: the state government and every county in Montana.
Nearby counties: Powell County (32 mi) · Teton County (48 mi) · Cascade County (50 mi) · Broadwater County (69 mi) · Granite County (70 mi) · Jefferson County (71 mi).