Sunnyside Mp 59.29 Reservoir dam
Sunnyside Mp 59.29 Reservoir
Located in Prosser, Washington, the Sunnyside Mp 59.29 Reservoir is a vital water resource managed by the Washington Dept of Ecology. Built in 2005 by CH2MHill, this earth dam reservoir serves primarily for irrigation purposes, with a storage capacity of 400 acre-feet. The reservoir covers an area of 21 acres and has a drainage area of 0.03 square miles, drawing water from the Spring Cr Wasteway - Offstream.
With a structural height of 41 feet and a hydraulic height of 44 feet, the Sunnyside Mp 59.29 Reservoir has a high hazard potential but is currently assessed to be in fair condition. The reservoir undergoes inspections every 5 years, with the last assessment conducted in October 2021. Despite its age, the dam continues to meet regulatory standards and serves as a critical component of the region's water management infrastructure, ensuring a reliable water supply for agricultural purposes in Benton County, Washington.
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 Sunnyside Mp 59.29 Reservoir -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Yakima River At Kiona | 1,020 cfs | → |
| Yakima River At Mabton | 4,700 cfs | → |
| Granger Drain At Granger | 46 cfs | → |
| Columbia River Below Priest Rapids Dam | 152,000 cfs | → |
| Umatilla River Near Umatilla | 222 cfs | → |
| Crab Creek Near Beverly | 176 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Sunnyside Mp 59.29 Reservoir.
Track Sunnyside Mp 59.29 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 Sunnyside Mp 59.29 Reservoir
Where does the data for Sunnyside Mp 59.29 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 Sunnyside Mp 59.29 Reservoir.