Dam Report

Johnson Lake Dam dam

Missouri, USA Tr-Calhoun Hollow-Clear Creek Hazard Low
Today high
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Tonight low
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Dam height
40ft
Hazard rating
Low
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Johnson Lake Dam -- None dam
Johnson Lake Dam None · Tr-Calhoun Hollow-Clear Creek
About this dam

Johnson Lake Dam

Johnson Lake Dam in Missouri, owned privately and regulated by state authorities, stands proudly as a vital irrigation structure along the TR-CALHOUN HOLLOW-CLEAR CREEK. This earth-type dam, reinforced with stone core and built on rock and soil foundations, reaches a height of 40 feet and spans 800 feet in length. With a storage capacity of 147 acre-feet, it serves the agricultural community efficiently while also offering a recreational surface area of 5 acres for locals to enjoy.

Despite its low hazard potential and moderate risk assessment, Johnson Lake Dam remains in good condition with regular state inspections ensuring its safety and functionality. The spillway, although uncontrolled, provides necessary water release to prevent overtopping during heavy rainfall events. Situated in Montgomery County, Missouri, this dam not only supports irrigation needs but also contributes to the overall water management and conservation efforts in the region. Enthusiasts of water resources and climate will find Johnson Lake Dam a fascinating example of sustainable infrastructure blending engineering with environmental stewardship.

StateNone
River / streamTr-Calhoun Hollow-Clear Creek
NID IDMO11473
Owner typePrivate
Primary purposeIrrigation
Dam typeEarth
Dam height40 ft
Dam length800 ft
Max storage147 AF
Normal storage147 AF
Surface area5.0 ac
Drainage area45.0 sq mi
Hazard potentialLow
ConditionNot Rated
Last inspectionThu, 02 Feb 2017 00:00:00 GMT

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.
Detailed forecast

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.

Hourly detail

Next 5 days, hour by hour

Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.

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Deep dive

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.

TimeConditionTemp (°F)Snow (in)Rain (in)Humidity (%)Wind (mps)Wind dir
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Long-term outlook

15-day temperature & precipitation

Daily temperatures, snow, and rain projected over the next two weeks.

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Regional inflow

Nearby streamflow gauges

USGS streamgauges around Johnson Lake Dam -- inflows here typically show up in storage 24-72 hours later.

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.

FAQ

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.

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