Dam Report

Lower Slate Lake Tailings Dam dam

Alaska, USA Lower Slate Creek Hazard Significant
Today high
--
Tonight low
--
Dam height
63ft
Hazard rating
Significant
Loading current conditions…
Loading next 24 hours…
Loading 7-day outlook…
Lower Slate Lake Tailings Dam -- None dam
Lower Slate Lake Tailings Dam None · Lower Slate Creek
About this dam

Lower Slate Lake Tailings Dam

The Lower Slate Lake Tailings Dam is a rockfill dam located in Juneau, Alaska, designed by Knight Piesold Engineers and completed in 2010. With a height of 63 feet and a hydraulic height of 57 feet, this dam serves the primary purpose of containing tailings from mining activities in the area. It has a storage capacity of 2,800 acre-feet and is regulated by the state agency AKDNR.

The dam has a significant hazard potential and underwent structural modifications in 2012. Despite this, the condition assessment in December 2020 deemed it to be satisfactory. The dam has a spillway width of 20 feet and a maximum discharge capacity of 1,020 cubic feet per second. It is situated on Lower Slate Creek and covers a surface area of 53 acres, with a drainage area of 1.05 square miles. The risk assessment for this dam is moderate, with an inspection frequency of 3 years to ensure its continued safety and integrity.

This dam is a crucial component of the mining operations in the region, providing storage for tailings and helping to manage water resources in the area. Its location in a remote part of Alaska makes its maintenance and inspection essential to prevent any potential hazards or environmental risks. Climate enthusiasts and water resource experts alike can appreciate the intricate design and function of the Lower Slate Lake Tailings Dam in this unique and environmentally sensitive landscape.

StateNone
River / streamLower Slate Creek
NID IDAK00308
Owner typePrivate
Primary purposeTailings
Dam typeRockfill
Year built2010
Dam height63 ft
Dam length480 ft
Max storage2,800 AF
Normal storage2,300 AF
Surface area53.0 ac
Drainage area1.1 sq mi
Hazard potentialSignificant
ConditionSatisfactory
Last inspectionTue, 28 Jul 2020 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.

Loading hourly forecast…
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
Loading detailed forecast…
Long-term outlook

15-day temperature & precipitation

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

Loading 15-day outlook…
Around the water

Make a day of it

Boat launches, lakeside camping, fishing access, and other reservoirs near Lower Slate Lake Tailings Dam.

Track Lower Slate Lake Tailings 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 Lower Slate Lake Tailings Dam

Where does the data for Lower Slate Lake Tailings 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 Significant 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.

More reservoirs

Other water bodies near here

Snoflo-tracked reservoirs and dams within driving distance of Lower Slate Lake Tailings Dam.

Premium feature

Favorites and alerts are part of Snoflo Premium. Save reservoirs, set storage thresholds, and get push notifications when conditions cross.

Upgrade to Premium Not now
🔔

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.

Open App Store