Milpitas dam
Milpitas
Milpitas, also known as Dam #2, is a federally owned structure located in Jolon, California, within the San Francisco District of the US Army. Built in 1960, this earth dam stands at a height of 22 feet and serves multiple purposes including fire protection, stock containment, and as a small fish pond. With a storage capacity of 50 acre-feet and a surface area of 3 acres, the dam plays a crucial role in water resource management for the San Antonio River.
Despite its low hazard potential, Milpitas poses a high risk due to its outdated risk assessment and lack of condition assessment data. The dam does not have a spillway and is not regulated by the state, raising concerns about its ability to withstand extreme weather events and prevent downstream flooding. While the dam is primarily managed by the US Army, it is not inspected frequently, with the last inspection dated back to April 2019. As climate change continues to impact water resources, there is a growing need for improved risk management measures and updated emergency action plans for structures like Milpitas.
For water resource and climate enthusiasts, Milpitas presents an intriguing case study of a federally owned dam with multiple purposes and a high risk assessment rating. As discussions around water management and climate resilience gain momentum, the importance of ensuring the safety and efficiency of structures like Milpitas becomes increasingly clear. With its location in Monterey County, California, and its role in the San Antonio River watershed, Milpitas serves as a reminder of the complexities and challenges associated with balancing water resource needs with 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 Milpitas -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Arroyo Seco Nr Soledad Ca | 24 cfs | → |
| San Antonio R Nr Lockwood Ca | · | → |
| San Lorenzo C Bl Bitterwater C Nr King City Ca | 0 cfs | → |
| Nacimiento R Bl Sapaque C Nr Bryson Ca | 2 cfs | → |
| Arroyo Seco Bl Reliz C Nr Soledad Ca | · | → |
| Salinas R A Soledad Ca | 209 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Milpitas.
Boat launches
- New Pleyto Road, Bradley
- Lynch Road, Bradley
- West Knoll Circle 10555, San Luis Obispo County
- Boat Launch San Luis Obispo County
- Well Road San Luis Obispo County
- Mistletoe Lane San Luis Obispo County
Campgrounds
- Old Wagon Cave Campground
- Nacimiento
- Nacimiento Campground
- Carrizo Springs Rustic Campsite
- Abc Camp Rustic Campsite
- Chalk Peak Camp
Fishing spots
- Lake San Antonio
- Lake Nacimiento
- Nacimiento Lake
- Barney Schwartz Park Lake
- El Estero
- Whale Rock Reservoir
Paddle runs
- Ventana Wilderness Boundary To Nf Boundary
- Headwaters To Sportsman's Club
- 0.25 Milesupstram Of The Impoundment At Sportsman's Lodge To 0.25 Miles Downstream Of The Impoundment At Sportsman's Lodge
- 0.25 Miles Downstream Of The Impoundment Of Sportsman's Lodge To Ventana Wilderness Boundary
- Headwaters North Fork Little Sur To Boy Scout Camp
- Boy Scout Camp To Confluence With Mainstem Little Sur
More reservoirs
Track Milpitas 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 Milpitas
Where does the data for Milpitas 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 Milpitas.