Frederick Graff | |
|---|---|
 | |
| Born | 27 August 1775 |
| Died | 13 April 1847 (aged 71) Philadelphia, Pennsylvania, US |
| Resting place | Laurel Hill Cemetery, Philadelphia, Pennsylvania, US |
| Occupation | Engineer |
| Engineering career | |
| Discipline | hydraulic engineer |
| Projects | Fairmount Water Works |
Frederick Graff (27 August 1775 – 13 April 1847) was an American hydraulic engineer who designed and built the Fairmount Water Works in Philadelphia, Pennsylvania, and unofficially invented the fire hydrant.