237,966 people (2024 Census estimate, +10.6% since 2020)
443 square miles of land · 537 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.
3 active community water systems list Delaware County in the area they serve, reporting 195,093 people served in all (a system that crosses county lines counts its whole population).
| DEL-CO WATER COMPANY, INC. surface water · private · OH2101412 | 150,000 served |
| DELAWARE CITY PWS surface water · local government · OH2100311 | 43,895 served |
| ASHLEY VILLAGE PWS buys surface water · local government · OH2100011 | 1,198 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 128 people were held in Delaware County's jail, in Vera's latest figure (2023), or 85 per 100,000 residents ages 15–64. In 2018 it was about 211.
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.
5 school districts have their office in Delaware County. School taxes are usually the largest part of a property tax bill.
Spent $379.1 million — $322.4 million to run schools, about $13,848 per student, plus $38.1 million on buildings and equipment. Money in: $336.6 million local (mostly property tax), $51.5 million state, $11.9 million federal. Long-term debt: $433.4 million.
Spent $87.1 million — $74.8 million to run schools, about $13,377 per student, plus $6.6 million on buildings and equipment. Money in: $56.2 million local (mostly property tax), $24.7 million state, $7.5 million federal. Long-term debt: $98.6 million.
Spent $64.5 million — $52 million to run schools, about $12,454 per student, plus $6.7 million on buildings and equipment. Money in: $56.3 million local (mostly property tax), $11.6 million state, $3.4 million federal. Long-term debt: $139.2 million.
Spent $38.6 million — $34.1 million to run schools, about $15,590 per student, plus $2.8 million on buildings and equipment. Money in: $31.7 million local (mostly property tax), $6.9 million state, $3.1 million federal. Long-term debt: $41 million.
Spent $18.3 million — $16.1 million to run schools, about $63,834 per student, plus $1.1 million on buildings and equipment. Money in: $19 million local (mostly property tax), $6.8 million state, $1.3 million federal.
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 Delaware County about $69.4 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.
266 bridges in Delaware County: 183 in good condition, 74 fair, and 9 poor (3.4%). “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.
| SR 257 over PED UNDERPASS AT ZOO · built 1970 | 11,179 vehicles a day |
| SR 37 over PRAIRIE RUN · built 1960 | 2,583 vehicles a day |
| SR 37 over HARSH DITCH · built 1960 | 2,583 vehicles a day |
| SR 257 over OTTAWA CREEK · built 1961 | 689 vehicles a day |
| OSTRANDER RD. over SCIOTO RIVER · built 1968 | 665 vehicles a day |
| S. WASHINGTON ST. over DELAWARE RUN · built 1992 | 499 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $77.8 million of work in Delaware County in fiscal 2025, about $363 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 Ohio 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 Delaware 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 Delaware County built: brayden.ozark@gmail.com.
More of Ohio: the state government and every county in Ohio.
Nearby counties: Union County (19 mi) · Morrow County (20 mi) · Franklin County (21 mi) · Marion County (23 mi) · Licking County (30 mi) · Knox County (32 mi).