Dam Report

Rowden Lake Dam dam

Illinois, USA Piasa Creek-Offstream Hazard Low
Today high
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Tonight low
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Dam height
40ft
Hazard rating
Low
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Rowden Lake Dam -- None dam
Rowden Lake Dam None · Piasa Creek-Offstream
About this dam

Rowden Lake Dam

Rowden Lake Dam, located in Alton, Illinois, is a privately owned structure designed by the USDA NRCS with a primary purpose of recreation. Completed in 1971, this earth dam stands at a height of 40 feet and stretches 380 feet in length, providing a storage capacity of 160 acre-feet. The dam is managed by the Illinois Department of Natural Resources and falls under state jurisdiction for regulation and inspection.

Despite its low hazard potential, Rowden Lake Dam is considered to have a moderate risk level, with an inspection frequency of 5 years. While the condition assessment is not available, the dam's emergency action plan status, risk assessment, and risk management measures are yet to be determined. The dam's spillway is uncontrolled, with an outlet gate that is similarly uncontrolled, posing a potential challenge in the event of a flood or emergency situation.

Overall, Rowden Lake Dam serves as a recreational resource in Jersey County, Illinois, along Piasa Creek. It is a significant part of the local landscape and provides both aesthetic appeal and functional benefits. However, ongoing monitoring and maintenance are essential to ensure the safety and longevity of this important water resource structure.

StateNone
River / streamPiasa Creek-Offstream
NID IDIL00900
Owner typePrivate
Primary purposeRecreation
Dam typeEarth
Year built1971
Dam height40 ft
Dam length380 ft
Max storage160 AF
Normal storage121 AF
Hazard potentialLow
ConditionNot Available
Last inspectionThu, 25 Sep 2014 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 Rowden Lake Dam -- inflows here typically show up in storage 24-72 hours later.

Track Rowden 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 Rowden Lake Dam

Where does the data for Rowden 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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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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