Dam Report

Soo Locks dam

Michigan, USA St Mary S Hazard High
Today high
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Tonight low
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Dam height
17ft
Hazard rating
High
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Soo Locks -- None dam
Soo Locks None · St Mary S
About this dam

Soo Locks

The Soo Locks, located in Sault Ste Marie, Michigan, are a critical part of the Great Lakes navigation system. Built in 1921, the complex consists of four locks that help ships navigate the St. Mary's River. The locks play a crucial role in facilitating the transportation of goods and resources between Lake Superior and the lower Great Lakes.

Despite their age, the Soo Locks are well-maintained by the US Army Corps of Engineers, who work diligently to address any potential risks and ensure the continuous operation of the locks. A recent risk assessment classified the complex as having a high risk due to aging infrastructure, which could lead to interruptions in navigation and power generation. To mitigate these risks, the USACE has implemented various measures, including routine monitoring, surveillance, and construction projects to address vulnerable features.

One of the key initiatives currently underway is the construction of a new, high-capacity lock to replace two decommissioned locks. This new lock will provide essential redundancy and ensure continuous operation, even in the event of closures or failures in the existing infrastructure. With these proactive measures in place, the Soo Locks continue to play a vital role in supporting water resource management and climate resilience in the region.

StateNone
River / streamSt Mary S
NID IDMI00650
Owner typeFederal
Primary purposeNavigation
Dam typeConcrete
Year built1921
Dam length968 ft
Max storage277,540,000 AF
Normal storage277,540,000 AF
Surface area20,255,000.0 ac
Drainage area181,000.0 sq mi
Hazard potentialHigh
ConditionNot Available
Last inspectionFri, 06 Aug 2021 12:00:00 GMT
EAP preparedYes

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 Soo Locks -- inflows here typically show up in storage 24-72 hours later.

StreamgaugeDischargeView
Tahquamenon River Near Paradise 1,560 cfs
Black River Near Garnet 38 cfs

Track Soo Locks 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 Soo Locks

Where does the data for Soo Locks 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 High 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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