Dam Report

Johnson Dam dam

Iowa, USA Tr-Whitebreast Creek Hazard Low
Today high
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Tonight low
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Dam height
31ft
Hazard rating
Low
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Johnson Dam -- None dam
Johnson Dam None · Tr-Whitebreast Creek
About this dam

Johnson Dam

Johnson Dam, located in Lucas County, Iowa, is a privately owned earth dam with a primary purpose of fire protection, stock, or small fish pond. Built in 1972 by the USDA NRCS, this dam stands at a height of 31 feet and spans 295 feet in length, with a storage capacity of 38 acre-feet. The dam is regulated by the Iowa DNR and undergoes regular inspections to ensure its safety and compliance with state regulations.

Situated on TR-WHITEBREAST CREEK near RED ROCK RESERVOIR, Johnson Dam serves as a recreational site in addition to its primary functions. The dam has a low hazard potential and a moderate risk assessment rating, indicating a manageable level of risk. While the dam's condition assessment is currently listed as "Not Rated," it is subject to periodic inspections and enforcement to maintain its integrity and safeguard against potential hazards.

Despite being a private structure, Johnson Dam plays a crucial role in water resource management in the region, providing storage capacity, fire protection, and recreational opportunities. With its strategic location and functional design, the dam serves as a vital asset for the community while contributing to the overall sustainability of the area's water resources and climate resilience efforts.

StateNone
River / streamTr-Whitebreast Creek
NID IDIA00587
Owner typePrivate
Primary purposeFire Protection, Stock, Or Small Fish Pond
Dam typeEarth
Year built1972
Dam height31 ft
Dam length295 ft
Max storage38 AF
Normal storage17 AF
Surface area2.9 ac
Drainage area0.2 sq mi
Hazard potentialLow
ConditionNot Rated
Last inspectionFri, 16 Feb 1968 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 Dam -- inflows here typically show up in storage 24-72 hours later.

Track Johnson 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 Dam

Where does the data for Johnson 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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Other water bodies near here

Snoflo-tracked reservoirs and dams within driving distance of Johnson Dam.

Premium feature

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Manage alerts in the Snoflo app

Custom alerts are configured in the iOS app -- favorite this dam, set a threshold, and you'll get a push the moment conditions cross.

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