Duffy's Marsh dam
Duffy's Marsh
Duffy's Marsh, located in Marquette, Wisconsin, is a privately-owned earth dam completed in 1997 with a primary purpose of recreation. This beautiful marsh area is situated along an unnamed tributary to the Grand River and covers a surface area of 1302 acres, with a drainage area of 6.82 square miles. The dam stands at a height of 8 feet and has a structural height of 8 feet, providing storage capacity of 5750 acre-feet.
With a low hazard potential and a fair condition assessment, Duffy's Marsh is a popular destination for water resource and climate enthusiasts looking to explore and enjoy the natural surroundings. Despite being privately owned, the dam is state-regulated and subject to inspections, ensuring safety measures are in place for visitors and the surrounding environment. The marsh offers a serene setting for recreational activities, attracting visitors to its tranquil waters and diverse wildlife.
In 2004, the dam underwent modifications, further enhancing its recreational offerings and maintaining its structural integrity. With a designated inspection frequency of 10 years, Duffy's Marsh continues to provide a safe and enjoyable environment for visitors to appreciate the beauty of Wisconsin's natural landscapes. Whether for birdwatching, fishing, or simply taking in the scenic views, Duffy's Marsh is a must-visit destination for those passionate about water resources and climate conservation.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Duffy's Marsh -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Fox River At Princeton | 1,120 cfs | → |
| White Creek @ Spring Grove Road Nr Green Lake | 6 cfs | → |
| Puchyan River Ds N. Lawson Drive Nr Green Lake | 115 cfs | → |
| Green Lake Inlet At Ct Highwy A Near Green Lake | 67 cfs | → |
| Fox River At Berlin | 1,570 cfs | → |
| Baraboo River Near Baraboo | 385 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Duffy's Marsh.
Boat launches
- Lower Locks Road Town Of Montello
- Lakeshore Drive 137, Montello
- Kilby Lake Road 218, Montello
- Fox River Road Town Of Buffalo
- Moon Lake Boat Landing
- County Road C Town Of Packwaukee
Campgrounds
- Crooked River Campground
- Indian Trails Campground
- Camp Grow
- Shiloh
- Gettysburg
- Veterans Memorial Field - Portage
Paddle runs
Track Duffy's Marsh in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Duffy's Marsh
Where does the data for Duffy's Marsh come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the Low hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Duffy's Marsh.