Sylvan

Sylvan is a gravity dam located in Cass County, Minnesota, built in 1913. It carries a High hazard potential classification and has a fair condition assessment.

About Sylvan

The primary purpose of Sylvan is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Allete, Inc. (private). It impounds the Crow Wing near Little Falls.

The dam stands 35 feet tall and stretches 1,154 feet across, creates a reservoir covering 1,280 acres, has a storage capacity of 9,216 acre-feet, and collects water from a drainage area of 3,575 square miles. Completed in 1913, the structure is over a century old.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 09/20/2021.

At 35 feet, this dam is taller than 82% of dams nationwide.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Minnesota dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardFair ConditionEmergency Action Plan: Yes

Location

StateMinnesota
CountyCass
Nearest CityLittle Falls
River/StreamCrow Wing
Coordinates46.30490, -94.37800

Physical Characteristics

Dam TypeGravity
NID Height35 ft
Dam Height35 ft
Dam Length1,154 ft
Year Completed1913 (113 years old)

Storage & Hydraulics

NID Storage9,216 acre-ft
Normal Storage9,216 acre-ft
Surface Area1,280 acres
Drainage Area3,575 sq mi
Max Discharge22,000 cfs
Spillway TypeControlled

Ownership & Safety

PurposeHydroelectric
OwnerAllete, Inc.
Owner TypePrivate
Hazard ClassificationHigh
Condition AssessmentFair
Last Inspection09/20/2021
Emergency Action PlanYes

Identifiers

NID IDMN00601
Federal IDMN00601
More InfoState Dam Safety Program

Nearby Dams