Spring Mountain Ranch Dam dam
Spring Mountain Ranch Dam
Spring Mountain Ranch Dam, also known as Lake Harriet, is a state-owned structure located in Las Vegas, Nevada. Built in 1945, this earth dam serves primarily for irrigation purposes, but also provides opportunities for recreation and water supply. With a height of 19 feet and a storage capacity of 22 acre-feet, the dam sits on the Blue Diamond Wash-TR, serving the surrounding area with essential water resources.
Despite its historical significance, Spring Mountain Ranch Dam has faced challenges in recent years. Classified as having a high hazard potential and poor condition assessment, the dam underwent hydraulic and structural modifications in 1978. Its spillway type is uncontrolled, with a maximum discharge capacity of 650 cubic feet per second. The dam's last inspection in February 2022 revealed the need for ongoing maintenance and risk management measures to ensure its safety and longevity for the community.
In the realm of water resource and climate enthusiasts, Spring Mountain Ranch Dam presents a case study of the intersection between infrastructure, environmental stewardship, and public safety. As Nevada's Department of Water Resources oversees its regulation and enforcement, stakeholders are tasked with addressing the dam's maintenance needs and risk assessment to protect both the surrounding ecosystem and the residents who rely on its water supply. With a moderate risk assessment rating and a history of modifications, the dam serves as a reminder of the ongoing challenges in managing and maintaining critical water infrastructure in the face of changing climatic conditions.
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 Spring Mountain Ranch Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Flamingo Wash At Nellis Blvd Nr Las Vegas | 4 cfs | → |
| Las Vegas Wash Nr Sahara Ave Nr Las Vegas | 2 cfs | → |
| Lv Wash Blw Flamingo Wash Confl Nr Las Vegas | 212 cfs | → |
| Sloan Channel At Charleston Blvd Nr Las Vegas | 1 cfs | → |
| Las Vegas Wash At Vegas Valley Dr Nr Las Vegas | 68 cfs | → |
| Sloan Channel Tr At Las Vegas Blvd Nr N Las Vegas | · | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Spring Mountain Ranch Dam.
Track Spring Mountain Ranch Dam 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 Spring Mountain Ranch Dam
Where does the data for Spring Mountain Ranch Dam 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 Spring Mountain Ranch Dam.