Macalexander #1 dam
Macalexander #1
Macalexander #1, a privately owned earth dam located in Memphis, Tennessee, was completed in 1938 to control water flow from the TRIBMISSISSIPPI RIVER. With a hydraulic height of 20.5 feet and a structural height of 22.5 feet, the dam spans 220 feet in length and has a storage capacity of 61 acre-feet. Despite being classified as having a low hazard potential, the dam is considered to have a moderate risk level, highlighting the importance of ongoing risk management measures.
Although Macalexander #1 is not regulated by the state of Tennessee, it undergoes inspections every five years, with the last inspection conducted in March 2020. The dam's condition is currently listed as "Not Rated," and it does not have an Emergency Action Plan (EAP) in place. Despite these factors, the dam's risk level is closely monitored, and measures are in place to mitigate potential issues. In the event of an emergency, the dam's owners will have to implement appropriate measures to ensure public safety and prevent flooding.
With its uncontrolled spillway and lack of outlet gates, Macalexander #1 presents unique challenges for its owners in terms of managing water flow and ensuring structural integrity. The dam's location near the Mississippi River tributary adds to its importance in regulating water levels and protecting surrounding areas from potential flooding. As water resource and climate enthusiasts, understanding the nuances of dams like Macalexander #1 is crucial for ensuring the sustainable management of water resources and the protection of communities in flood-prone regions.
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 Macalexander #1 -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Mississippi River At Memphis | 628,000 cfs | → |
| Fletcher Creek At Sycamore View Road At Memphis | 7 cfs | → |
| Wolf River At Germantown | 1,240 cfs | → |
| Nonconnah Creek Near Germantown | 107 cfs | → |
| Loosahatchie River Near Arlington | 177 cfs | → |
| Coldwater River Nr Olive Branch | 395 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Macalexander #1.
Track Macalexander #1 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 Macalexander #1
Where does the data for Macalexander #1 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 Macalexander #1.