6Total Dams
2High Hazard
0Significant
Dam Safety in Nassau County, New York
Nassau County has 6 dams tracked in the National Inventory of Dams. Of these, 2 are classified as high hazard — meaning failure would probably cause loss of human life. Currently, 1 dam has a condition assessment of poor or unsatisfactory.
The average dam in Nassau County is 116 years old. The most common purpose is recreation. The tallest dam is Hempstead Lake Dam at 24 ft.
Explore more: Oldest dams in New York · Tallest dams · High risk dams · Largest reservoirs
| Dam | Hazard | Condition | Height (ft) | Purpose | Year |
|---|---|---|---|---|---|
| Hempstead Lake Dam | High | Satisfactory | 24 | Recreation | 1873 |
| Upper Massapequa Lake Dam | High | Poor | 11 | Recreation | 1900 |
| Mill Pond Dam | Low | Not assessed | 18 | Other | 1983 |
| South Pond Dam | Low | Not assessed | 13 | Water Supply | 1903 |
| Massapequa Lake Dam | Low | Not assessed | 11 | Recreation | 1890 |
| Leeds Pond Dam | Low | Not assessed | 10 | Recreation | 1908 |