Ipuolono Reservoir Reservoir Report

Last Updated: December 19, 2025

Located in Kalaheo, Hawaii, the Ipuolono Reservoir, also known as No.


°F

°F

mph

Wind

%

Humidity

Summary

8 Reservoir, is a privately owned earth dam constructed in 1910 primarily for irrigation purposes. With a dam height of 45 feet and a storage capacity of 450 acre-feet, this reservoir serves as a vital water resource in the region, covering a surface area of 23 acres and draining an area of 1.96 square miles through the Kalaheo Gulch.

Despite its historical significance and essential role in supporting local agriculture, the Ipuolono Reservoir poses a high hazard potential and is currently in poor condition as of the last assessment in 2009. The dam's inspection frequency is set at every five years, with the last inspection conducted in July 2018. While the risk assessment for the reservoir is moderate, there is a need for enhanced risk management measures and potential updates to emergency action plans to ensure the safety and sustainability of this critical water infrastructure in the face of changing climate conditions.

Year Completed

1910

Dam Length

680

Dam Height

45

River Or Stream

KALAHEO GULCH

Primary Dam Type

Earth

Surface Area

23

Hydraulic Height

45

Drainage Area

1.96

Nid Storage

450

Structural Height

50

Hazard Potential

High

Foundations

Unlisted/Unknown

Nid Height

50
       
Seasonal Comparison

Weather Forecast

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. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
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. Investigations and studies are necessary.
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.
Not Available
Dams for which the condition assessment is restricted to approved government users.

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, environment 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.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.