Leonard Johnson dam
Leonard Johnson
Leonard Johnson is a privately owned dam located in Alturas, California, along Dry Creek. Built in 1948, this earth dam stands at 18 feet in height and spans 720 feet in length, providing essential water supply for irrigation purposes. Managed by the California Department of Water Resources (DWR) under the Safety of Dams program, the dam is regulated, inspected, and enforced by the state to ensure its safety and functionality.
With a storage capacity of 120 acre-feet, Leonard Johnson serves as a crucial water source for the surrounding area, supporting agricultural activities and local water supply needs. Despite its age, the dam has a low hazard potential and is assessed to be in satisfactory condition as of September 2017. Regular inspections, the most recent one conducted in June 2020, help to monitor the dam's integrity and ensure that it meets safety standards for continued operation.
As a significant infrastructure for water management, Leonard Johnson plays a vital role in the water resource system of Modoc County, California. With its strategic location and purposeful design, this dam exemplifies the importance of sustainable water supply in the face of changing climate patterns and increasing water demands. Enthusiasts of water resources and climate resilience can appreciate the careful regulation and maintenance efforts put into ensuring the functionality and safety of Leonard Johnson for the benefit of the local community and ecosystem.
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 Leonard Johnson -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Trinity Rv At Romayor | 8,140 cfs | → |
| Menard Ck Nr Rye | 54 cfs | → |
| Trinity Rv At Liberty | 7,570 cfs | → |
| E Fk San Jacinto Rv Nr Cleveland | 73 cfs | → |
| Luce Bayou Abv Lk Houston Nr Huffman | 1 cfs | → |
| Trinity Rv Nr Goodrich | 8,590 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Leonard Johnson.
Boat launches
- Big Sage Road Modoc County
- Logan Slough Boating Site
- Green Springs Boating Site
- Goose Lake State Park
- Lily Lake Boating Site
- Duncan North Boating Site
Campgrounds
Fishing spots
Track Leonard Johnson 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 Leonard Johnson
Where does the data for Leonard Johnson 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 Leonard Johnson.