Elua Reservoir dam
Elua Reservoir
Elua Reservoir, also known as No. 2 Reservoir, is a privately owned water resource located in Kalaheo, Hawaii. Built in 1902, this Earth dam stands at a height of 30 feet and has a storage capacity of 340 acre-feet, primarily used for irrigation purposes. With a surface area of 13 acres and a drainage area of 1.15 square miles, the reservoir plays a crucial role in providing water for agricultural activities in the region.
Managed and regulated by the Hawaii Department of Land and Natural Resources, Elua Reservoir has a spillway width of 67 feet and a maximum discharge capacity of 4700 cubic feet per second. Despite being classified as having a high hazard potential, the dam is currently in fair condition and undergoes regular inspections every 5 years. The risk assessment for the reservoir is moderate (3), highlighting the importance of ongoing monitoring and management to ensure the safety and efficiency of this essential water resource in Kauai, Hawaii.
For water resource and climate enthusiasts, Elua Reservoir offers a fascinating glimpse into the intricate infrastructure that supports agricultural irrigation in Hawaii. As a historic dam with a significant storage capacity, it serves as a vital lifeline for farmers in the region, while also posing challenges in terms of hazard potential and risk management. With its unique design and location within the Kalaheo Gulch, Elua Reservoir stands as a testament to the resilience and innovation required to sustain water resources in the face of changing climates and environmental pressures.
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.
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.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
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.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Elua Reservoir -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Waimea River Nr Waimea | 131 cfs | → |
| Waialae Str At Alt 3 | 6 cfs | → |
| Sf Wailua River Nr Lihue | 157 cfs | → |
| Eb Of Nf Wailua River Nr Lihue | 48 cfs | → |
| Left Branch Opaekaa Str Nr Kapaa | 5 cfs | → |
| Wainiha River Nr Hanalei | 145 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Elua Reservoir.
Track Elua Reservoir 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.
About Elua Reservoir
Where does the data for Elua Reservoir 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 High 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.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Elua Reservoir.