Mcdonald dam
Mcdonald
Mcdonald is a federal-owned irrigation dam located in Moiese, Montana, along the Post Creek. Built in 1920 by the Bureau of Indian Affairs, this Earth dam stands at 47 feet tall and stretches 1495 feet in length. With a capacity of 8225 acre-feet, Mcdonald serves the primary purpose of irrigation in the region. Despite being a crucial water resource, the dam has a high hazard potential and is classified as very high risk, emphasizing the need for careful monitoring and maintenance.
Owned, funded, designed, constructed, regulated, and inspected by the Bureau of Indian Affairs, Mcdonald is a significant water infrastructure project in the region. While it has not been assessed for condition recently, emergency action plans have been prepared and updated to ensure timely responses in case of any unforeseen events. With a high hazard potential, the dam's risk management measures are critical to safeguarding the surrounding communities and infrastructure from potential harm.
With a controlled spillway type and a history dating back to the early 20th century, Mcdonald plays a vital role in supporting agricultural activities in the area. Despite its age, the dam continues to provide essential irrigation water, highlighting the importance of ongoing monitoring and risk assessment to ensure its continued safe operation. For water resource and climate enthusiasts, Mcdonald presents a fascinating case study in the intersection of infrastructure, environmental stewardship, and community safety.
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 Mcdonald -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Sacramento R A Colusa Ca | 6,930 cfs | → |
| Sacramento R Bl Wilkins Slough Nr Grimes Ca | 5,000 cfs | → |
| Yuba R Nr Marysville Ca | 1,180 cfs | → |
| Bear R Nr Wheatland Ca | 38 cfs | → |
| Deer C Nr Smartville Ca | 17 cfs | → |
| Cache C A Rumsey Ca | 730 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Mcdonald.
Boat launches
Campgrounds
- North Crow Creek
- Lindbergh Lake Campground
- Lindbergh Lake
- Old Condon Ranger Station
- Holland Lake Campground Larch Loop
- Holland Lake
Fishing spots
- Blacktail Lake
- Lake Alva
- Big Salmon Lake
- Big Salmon Creek
- Deep Creek Fishing Access
- Petty Creek Fishing Access
Paddle runs
- Headwaters, Sec. 17, T19n, R15w To Seeley Lake, Sec. 20, T17n, R15w
- Wrangle Creek Headwaters, Sec. 18, T15n, R18w To Mainstem, Sec. 21, T15n, R18w
- Headwaters, Sec. 7, T18n, R14w To Morrell Falls, Sec. 24, T18n, R15w
- Lake Creek Headwaters, Sec. 30, T15n, R18w To Mainstem, Sec. 21, T15n, R18w
- Morrell Falls, Sec. 24, T18n, R15w To Morrell Falls Trailhead, Sec. 36, T18n, R15w
- High Falls Creek Headwaters, Sec. 5, T14n, R18w To Mainstem, Sec. 2, T14n, R18w
More reservoirs
Track Mcdonald 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 Mcdonald
Where does the data for Mcdonald 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 Mcdonald.