Johnson Lake Dam dam
Johnson Lake Dam
Johnson Lake Dam, also known as Floyds Lake Dam, is a private earth dam located in Henry, Georgia. Completed in 1954, the dam stands at a height of 15 feet and has a length of 580 feet, creating a reservoir with a storage capacity of 112.5 acre-feet. The primary purpose of this dam is for recreation, providing a serene spot for water resource and climate enthusiasts to enjoy.
Despite being classified as having low hazard potential, Johnson Lake Dam is subject to regular inspections, with the last one conducted in March 2017. With a moderate risk assessment rating of 3, there are currently no emergency action plans in place for the dam. The dam features uncontrolled spillways and outlets, and is not regulated or permitted by the state, posing a moderate level of risk that may be of interest to water resource and climate enthusiasts in the area.
For those interested in exploring the water infrastructure of Georgia, Johnson Lake Dam offers a glimpse into the engineering and environmental considerations of private dams. With its peaceful surroundings and recreational opportunities, this dam serves as a focal point for both enjoyment and study in the realm of water resources and climate impact mitigation.
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 Johnson Lake Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Flint River Near Lovejoy | 43 cfs | → |
| Pates Creek At Buster Lewis Rd Near Flippen | 12 cfs | → |
| Shoal Creek At Shoal Creek Rd | 8 cfs | → |
| Flint River Near Griffin | 67 cfs | → |
| Line Creek Near Senoia | 15 cfs | → |
| Honey Creek At Ga 212 | 7 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Johnson Lake Dam.
Boat launches
- West Mcintosh Road Spalding County
- Burch Lake Road Fayette County
- Lakeshore Drive Henry County
- Peachtree Parkway 488, Shake Rag
- 1124 Peachtree City
- Pine Crest Drive 127, Peachtree City
Campgrounds
- High Falls State Park
- Indian Springs State Park
- Newton Factory Shoals Rec Area
- Cochran Mill County Park
- Rush Creek Campground
- Gladesville Campground
Fishing spots
- Griffin City Reservoir
- Clayton County International Park
- Padgett Lake
- Jester Creek
- High Falls Lake
- Indian Springs State Park Lake
Track Johnson Lake Dam 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 Johnson Lake Dam
Where does the data for Johnson Lake Dam 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 Johnson Lake Dam.