Dam Report

Holland Pond Dam dam

Illinois, USA Tr- Piasa Creek Hazard Undetermined
Today high
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Tonight low
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Dam height
31ft
Hazard rating
Undetermined
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Holland Pond Dam -- None dam
Holland Pond Dam None · Tr- Piasa Creek
About this dam

Holland Pond Dam

Holland Pond Dam, located in Alton on Mississippi, Illinois, was completed in 1963 by the USDA NRCS and serves multiple purposes including recreation and other activities. The earth dam stands at a height of 31 feet and has a length of 180 feet, with a storage capacity of 38 acre-feet. The dam is situated on Tr- Piasa Creek and is surrounded by a drainage area of 0.09 square miles, with a maximum discharge capacity of 291 cubic feet per second.

Despite being classified as having an undetermined hazard potential, the dam is currently in a condition assessment status of "Not Available." The risk assessment for the dam is moderate, with a DSAC assigned date still pending. The spillway type is uncontrolled with a width of 36 feet, and the outlet gates are also uncontrolled. The dam is owned privately and falls under the jurisdiction of the USDA NRCS, with no state regulatory agency overseeing its operations. For water resource and climate enthusiasts, Holland Pond Dam presents an interesting case study in dam management and the importance of regular inspections and maintenance to ensure public safety and environmental protection.

StateNone
River / streamTr- Piasa Creek
NID IDIL40049
Owner typePrivate
Primary purposeOther
Dam typeEarth
Year built1963
Dam height31 ft
Dam length180 ft
Max storage38 AF
Normal storage26 AF
Surface area3.0 ac
Drainage area0.1 sq mi
Hazard potentialUndetermined
ConditionNot Available

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 Holland Pond Dam -- inflows here typically show up in storage 24-72 hours later.

Track Holland Pond Dam in the Snoflo app

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FAQ

About Holland Pond Dam

Where does the data for Holland Pond 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 Undetermined 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

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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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