417,029 people (2024 Census estimate, +2.3% since 2020)
550 square miles of land · 759 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.
73 active community water systems list Waukesha County in the area they serve, reporting 248,566 people served in all (a system that crosses county lines counts its whole population).
| WAUKESHA WATER UTILITY buys surface water · local government · WI2680238 | 70,718 served |
| BROOKFIELD WATER UTILITY groundwater · local government · WI2680253 | 29,070 served |
| NEW BERLIN WATER UTILITY buys surface water · local government · WI2680217 | 27,899 served |
| MENOMONEE FALLS WW - SURFACE WATER buys surface water · local government · WI2680082 | 23,867 served |
| OCONOMOWOC WATERWORKS groundwater · local government · WI2680227 | 15,805 served |
| SUSSEX VILLAGE HALL & WATER UTILITY groundwater · local government · WI2680233 | 11,750 served |
| HARTLAND WATERWORKS groundwater · local government · WI2680205 | 9,212 served |
| PEWAUKEE CITY WATER AND SEWER UTILITY groundwater · local government · WI2680214 | 8,671 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 475 people were held in Waukesha County's jail, in Vera's latest figure (2025). In 2020 it was about 397.
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.
19 school districts have their office in Waukesha County. School taxes are usually the largest part of a property tax bill.
Spent $181 million — $158 million to run schools, about $13,325 per student, plus $6.7 million on buildings and equipment. Money in: $84.6 million local (mostly property tax), $93.8 million state, $20.9 million federal. Long-term debt: $27.7 million.
Spent $120.1 million — $109.8 million to run schools, about $14,116 per student, plus $5.9 million on buildings and equipment. Money in: $74.1 million local (mostly property tax), $47.5 million state, $9.6 million federal. Long-term debt: $32.5 million.
Spent $75.2 million — $68.5 million to run schools, about $13,409 per student, plus $1.4 million on buildings and equipment. Money in: $37.8 million local (mostly property tax), $40.4 million state, $5.2 million federal. Long-term debt: $49.1 million.
Spent $80.7 million — $68.2 million to run schools, about $13,592 per student, plus $2.5 million on buildings and equipment. Money in: $64.7 million local (mostly property tax), $29.1 million state, $5.6 million federal. Long-term debt: $70.8 million.
Spent $68.7 million — $61.7 million to run schools, about $12,318 per student, plus $2.1 million on buildings and equipment. Money in: $36.2 million local (mostly property tax), $39.5 million state, $6.3 million federal. Long-term debt: $32.4 million.
Spent $80.5 million — $66.9 million to run schools, about $14,038 per student, plus $8.7 million on buildings and equipment. Money in: $32.6 million local (mostly property tax), $39.9 million state, $7.2 million federal. Long-term debt: $79.5 million.
Spent $63.3 million — $57.2 million to run schools, about $13,449 per student, plus $901,000 on buildings and equipment. Money in: $43.1 million local (mostly property tax), $24.9 million state, $7.2 million federal. Long-term debt: $27.6 million.
Spent $60.1 million — $52 million to run schools, about $13,290 per student, plus $1.8 million on buildings and equipment. Money in: $38.9 million local (mostly property tax), $25.9 million state, $4.6 million federal. Long-term debt: $35.8 million.
And 11 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 Waukesha County about $138.3 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very High; social vulnerability: Very Low.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
370 bridges in Waukesha County: 176 in good condition, 174 fair, and 20 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.
| CTH F NB over IH 94 · built 1977 | 17,650 vehicles a day |
| CTH VV WB (SILVER over MENOMONEE RIVER · built 1964 | 9,600 vehicles a day |
| CTH C (GENESEE ST) over IH 94 · built 1963 | 9,000 vehicles a day |
| CTH I (BELOIT ROAD over CALHOUN CREEK · built 1976 | 9,000 vehicles a day |
| LRD GEBHARDT RD over DOUSMAN DITCH · built 1966 | 5,100 vehicles a day |
| LRD OVERVIEW DR over BUTLER DITCH · built 1988 | 2,837 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $82.5 million of work in Waukesha County in fiscal 2025, about $203 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 Wisconsin 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 Waukesha 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 Waukesha County built: brayden.ozark@gmail.com.
More of Wisconsin: the state government and every county in Wisconsin.
Nearby counties: Milwaukee County (23 mi) · Jefferson County (24 mi) · Washington County (26 mi) · Walworth County (27 mi) · Racine County (31 mi) · Dodge County (35 mi).