Duffy's Marsh is an earth dam located in Marquette County, Wisconsin, built in 1997. It carries a Low hazard potential classification and has a fair condition assessment.
Dam profile
NID height · 8 ft8 ft tall and 10,000 ft long. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Duffy's Marsh
Duffy's Marsh is a dam in Marquette, Wisconsin. The dam is owned by Duffy Marsh Property Owners (private). It impounds the Unnamed Trib to Grand River.
The dam stands 8 feet tall and stretches 10,000 feet across, creates a reservoir covering 1,302 acres, has a maximum storage capacity of 5,750 acre-feet, and collects water from a drainage area of 6 square miles. Completed in 1997, the structure is 29 years old.
This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. The most recent inspection on record was 04/27/2021.
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Location
| State | Wisconsin |
| County | Marquette |
| River/Stream | Unnamed Trib to Grand River |
| Coordinates | 43.73782, -89.30688 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 8 ft |
| Dam Height | 8 ft |
| Dam Length | 10,000 ft |
| Year Completed | 1997 (29 years old) |
Storage & Hydraulics
| NID Storage | 5,750 acre-ft |
| Max Storage | 5,750 acre-ft |
| Surface Area | 1,302 acres |
| Drainage Area | 6 sq mi |
Ownership & Safety
| Purpose | Other |
| Owner | Duffy Marsh Property Owners |
| Owner Type | Private |
| Hazard Classification | Low |
| Condition Assessment | Fair |
| Last Inspection | 04/27/2021 |
| Emergency Action Plan | No |
Identifiers
| NID ID | WI01211 |
| Federal ID | WI01211 |
| More Info | State Dam Safety Program |