Magma Retarding dam
Magma Retarding
Magma Retarding, located in Pinal, Arizona, is a privately owned structure designed by USDA NRCS with the primary purpose of flood risk reduction along the Gila River. Completed in 1964, this earth dam stands at a height of 21 feet and spans 28,900 feet in length. With a storage capacity of 18,684 acre-feet and a surface area of 935 acres, Magma Retarding plays a crucial role in managing water resources in the region.
Managed by the Arizona Department of Water Resources and regulated by state agencies, Magma Retarding has a high hazard potential but is currently in satisfactory condition. The structure features an uncontrolled spillway with a width of 150 feet and outlets that are also uncontrolled. Despite its moderate risk rating, Magma Retarding serves as a vital component of the flood control infrastructure in the area, helping to protect downstream communities and ecosystems from the impacts of extreme weather events.
As a key element of water resource management in Arizona, Magma Retarding underscores the importance of proactive maintenance and monitoring to ensure its continued effectiveness in mitigating flood risks. With its strategic location along the Gila River and strong regulatory oversight, this structure represents a valuable asset for climate resilience and disaster preparedness in the region.
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 Magma Retarding -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Florence-Casa Grande Canal | 176 cfs | → |
| Queen Creek Below Whitlow Dam Nr Superior | 1 cfs | → |
| Gila River At Kelvin | 153 cfs | → |
| Pinto Cr Blw Haunted Canyon Nr Miami | · | → |
| Salt River Blw Stewart Mountain Dam | 567 cfs | → |
| Pinto Creek Near Miami | 1 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Magma Retarding.
Boat launches
- East Rolls Road Pinal County
- East Mission Bay Drive Gilbert
- Laguna Boat Ramp
- Wanda Dalton Road Kearny
- Apache Trail Maricopa County
Campgrounds
- Oak Flat
- Goldfield Camp
- Lost Dutchman State Park
- Cholla Forest Primitive Group Camp
- Legacy Adventures Ministry, Inc
- Usery Mountain
Fishing spots
Paddle runs
- Telegraph Creek - Forest Road #4 To Confluence With Arnett Creek
- Arnett Creek - Forest Road #4 To Middle Of Sec 7,T2s, R12e
- Kelvin Run
- Lower Salt
- Boundary Of The Primary Jurisdiction Below Stewart Mountain Dam To Salt River Indian Reservation Boundary
- Salt River Indian Reservation Boundary To Immediately Above Granite Reef Dam Impoundment
Track Magma Retarding 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 Magma Retarding
Where does the data for Magma Retarding 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 High 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 Magma Retarding.