Mississippi River Lock And Dam 21

Significant HazardNot Available ConditionEmergency Action Plan: Yes

Location

StateMissouri
CountyAdams
Nearest CityHANNIBAL
River/StreamMISSISSIPPI RIVER
Coordinates39.90448, -91.42988

Physical Characteristics

Dam TypeConcrete
NID Height48 ft
Dam Length3,116 ft
Year Completed1938 (88 years old)

Storage & Hydraulics

NID Storage62,000 acre-ft
Max Storage62,000 acre-ft
Surface Area8,843 acres
Drainage Area135,000 sq mi
Max Discharge529,000 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeNavigation
OwnerUSACE - Rock Island District
Owner TypeFederal
Hazard ClassificationSignificant
Condition AssessmentNot Available
Last Inspection07/27/2023
Emergency Action PlanYes

Identifiers

NID IDMO10304
Federal IDMO10304
More InfoState Dam Safety Program

Nearby Dams

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