Upper Big Nemaha 15-a

Upper Big Nemaha 15-a is an earth dam located in Lancaster County, Nebraska, built in 1970. It carries a Low hazard potential classification and has a poor condition assessment.

About Upper Big Nemaha 15-a

The primary purpose of Upper Big Nemaha 15-a is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Nemaha Natural Resources District (local government). It impounds the Tr-mid Br Big Nemaha River near Firth.

The dam stands 24 feet tall and stretches 662 feet across, creates a reservoir covering 8 acres, has a maximum storage capacity of 242 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1970, the structure is well into its service life at over 50 years old.

This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. The most recent inspection on record was 06/10/2021.

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

Low HazardPoor ConditionEmergency Action Plan: Not Required

Location

StateNebraska
CountyLancaster
Nearest CityFirth
River/StreamTr-mid Br Big Nemaha River
Coordinates40.55943, -96.69763

Physical Characteristics

Dam TypeEarth
NID Height24 ft
Dam Height20 ft
Dam Length662 ft
Year Completed1970 (56 years old)

Storage & Hydraulics

NID Storage242 acre-ft
Max Storage242 acre-ft
Normal Storage24 acre-ft
Surface Area8 acres
Drainage Area0 sq mi
Max Discharge1,402 cfs

Ownership & Safety

PurposeFlood Risk Reduction
OwnerNemaha Natural Resources District
Owner TypeLocal Government
Hazard ClassificationLow
Condition AssessmentPoor
Last Inspection06/10/2021
Emergency Action PlanNot Required

Identifiers

NID IDNE00545
Federal IDNE00545
More InfoState Dam Safety Program

Nearby Dams