Tom Ranch Lake No 2 Dam
Tom Ranch Lake No 2 Dam
Tom Ranch Lake No 2 Dam, also known as Edmund Tom Ranch Pond, is a privately owned earth dam located in Atascosa, Texas. Built in 1973 by the USDA NRCS, this dam serves multiple purposes including fire protection, stock, and small fish pond. With a height of 18 feet and a length of 1140 feet, the dam has a storage capacity of 240 acre-feet and covers a surface area of 8 acres.
Although not regulated by the state, Tom Ranch Lake No 2 Dam is designed to withstand high-risk situations with a hazard potential of "Not Available" and a risk assessment rating of "High (2)". Despite the lack of a spillway, the dam is equipped with one outlet gate and is not associated with any locks. While the condition assessment remains unrated, the dam is inspected periodically to ensure its structural integrity and compliance with safety standards.
Located along the TR-Atascosa River and under the jurisdiction of the Galveston District, Tom Ranch Lake No 2 Dam stands as a vital resource for water management and climate resilience in the region. As an essential component of the local ecosystem, this dam plays a crucial role in mitigating flood risks, providing water for agricultural and recreational purposes, and supporting the overall sustainability of the surrounding area.
Inside the reservoir
The real shoreline of this water body, with a depth model scaled so the basin holds exactly its recorded storage. Drag to orbit, scroll to zoom, and use the slider to drain and refill it. Click anywhere on the basin for the modelled depth there.
NID normal pool storage (146 AF) over this shoreline implies a 71 ft basin, deeper than the 18 ft dam. Depth capped to the dam; storage shown is modelled, not NID.
How this is built. The shoreline is the National Hydrography
Dataset polygon for this water body,
matched to the dam by proximity and confirmed by comparing its area with the
National Inventory of Dams surface area (agreement 0.534×).
Depth is modelled, not surveyed: the basin is shaped by distance from
shore — deep in open water, shallow in the bays — and scaled so its
volume equals the recorded storage. No national bathymetric survey exists for
US reservoirs. Treat the shoreline, area and volume as measured, and the depth
distribution as an informed approximation.
Above normal pool, water is shown rising within the normal-pool
shoreline. Where it would actually spread depends on the surrounding
terrain, which is not modelled here — a reservoir in a steep canyon barely
widens, one on flat ground can spread a long way. This is a depth and volume
figure, not an inundation map. Official inundation mapping for a dam
comes from its Emergency Action Plan.
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 Tom Ranch Lake No 2 Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Atascosa Rv At Whitsett | 3 cfs | → |
| Atascosa Rv Nr Mccoy | · | → |
| Choke Canyon Res Owc Nr Three Rivers | 30 cfs | → |
| San Miguel Ck Nr Tilden | · | → |
| Nueces Rv Nr Three Rivers | 30 cfs | → |
| San Antonio Rv Nr Falls City | 259 cfs | → |
About Tom Ranch Lake No 2 Dam
Where does the data for Tom Ranch Lake No 2 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 Not Available 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 below 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.
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.