S-121 dam
S-121
S-121 is a state-regulated flood risk reduction structure located in Cutler Ridge, Miami-Dade, Florida. This dam, primarily owned and operated by the state, plays a crucial role in managing water resources in the area by controlling the flow of the Cutler Drain Canal (C-100C). With a height of 11 feet and a maximum storage capacity of 1000 acre-feet, S-121 serves as a significant infrastructure for mitigating flood risks in the region.
Despite its importance, S-121 has not been rated for its condition assessment, and the last inspection date recorded was in 1905. The dam is categorized as having a significant hazard potential, highlighting the critical need for regular maintenance and monitoring to ensure its structural integrity and effectiveness in flood control. Although the dam has not been modified in recent years, its operational status and emergency preparedness measures, including the existence of an emergency action plan, remain unspecified.
For water resource and climate enthusiasts, S-121 presents an intriguing case study for examining the role of state-owned flood risk reduction structures in managing water flow and mitigating potential hazards. The dam's location in a densely populated area underscores the importance of regular inspection and maintenance to protect surrounding communities from the impacts of flooding. As climate change continues to pose challenges to water resource management, ensuring the resilience and functionality of structures like S-121 is essential for safeguarding both people and the environment in the face of changing weather patterns and increasing flood risks.
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 S-121 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Tamiami Canal Near Coral Gables | 47 cfs | → |
| Levee 31 North Extension At 5 Mile Nr West Miami F | 121 cfs | → |
| Levee 31 North Extension At 4 Mile Nr West Miami F | 85 cfs | → |
| Levee 31 North Extension At 7 Mile Nr West Miami F | 74 cfs | → |
| Levee 31 North Extension At 3 Mile Nr West Miami F | 42 cfs | → |
| Levee 31 North Extension At 1 Mile Nr West Miami | 94 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near S-121.
Boat launches
- North Snapper Creek Drive 9746-9788, Miami
- Falls Boat Launch
- Southwest Guadalajara Street Coral Gables
- Tamiami Trail, Florida
- L-29 Miami-Dade County
- Crandon Park Marina
Campgrounds
- Larry And Penny Thompson Park
- Boca Chita Key Campground
- Elliott Key Campground
- Cb Smith Park
- Long Pine Key - Everglades National Park
- Long Pine Key Campground
Track S-121 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 S-121
Where does the data for S-121 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.