Hagmaier South dam
Hagmaier South
Hagmaier South, located in Marin, California, is a federal-owned dam managed by the National Park Service. Built in 1944 on Olema Creek, this earth dam stands at a height of 24 feet, with a storage capacity of 20 acre-feet. With a significant hazard potential, the dam's condition assessment is currently listed as "Not Available," and its last inspection was conducted in September 2015.
Despite being under federal ownership and regulation, Hagmaier South does not fall under state jurisdiction or permitting. The dam serves primarily to control water flow and storage in the area, with a normal storage capacity of 13 acre-feet. While the dam's risk assessment, emergency action plan, and inundation maps are not readily available, the National Park Service is responsible for its operations, inspections, and emergency preparedness.
Located in the district of San Francisco, Hagmaier South plays a crucial role in water resource management in the region. With its historical significance dating back to World War II, the dam continues to be a key structure in the National Park Service's portfolio. Climate and water resource enthusiasts would find Hagmaier South's unique characteristics and management under federal oversight intriguing in the context of sustainable infrastructure development and climate adaptation efforts.
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 Hagmaier South -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Lagunitas C A Sp Taylor State Pk Ca | 14 cfs | → |
| Olema C A Vedanta Bridge A Olema Ca | 1 cfs | → |
| Lagunitas C Nr Pt Reyes Station Ca | 16 cfs | → |
| Corte Madera C A Ross Ca | 3 cfs | → |
| Redwood C A Hwy 1 Bridge A Muir Beach Ca | 2 cfs | → |
| Novato C A Novato Ca | 1 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Hagmaier South.
Boat launches
- Steven Way 98, Marin County
- Marin Rod And Gun Club Pier 2675, San Rafael
- Calypso Shores 23, Marin County
- Turney Street Boat Ramp
- Sears Point Road 100-138, Novato
- Harding Road San Francisco
Campgrounds
- Five Brooks Horse Camp
- Camp Taylor
- Madrone Group Camp
- Orchard Hill Campground
- Glen Campground
- Olema Campground
Fishing spots
- Lake Lagunitas
- Berkeley Yacht Harbor
- San Pablo Reservoir
- Lake Temescal
- Bodega Harbor
- 9th Street Boat Ramp
Paddle runs
- Headwaters To Ends One Quarter Mile South Of Bear Valley Road Bridge Segment 1: Ends 1/4 Mile South Of Bear Valley Road Bridge Segment 2: Caltrans Corporation Yard At Point Reyes Staton.
- Olema Ranch Campground To Caltrans Corporation Yard At Point Reyes Station
- Headwaters To Mouth
Track Hagmaier South 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 Hagmaier South
Where does the data for Hagmaier South 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 Significant 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 Hagmaier South.