Green Peter Reservoir
Green Peter Reservoir is managed by U.S. Army Corps of Engineers — Portland District. Lake Insights displays its latest available elevation from USACE NWP District.
Lake Status
- 7-day trend
- Falling
- 7-day change
- Down 3.94 ft
- 30-day change
- Down 3.94 ft
- Last updated
- 1 hour ago
Watershed drought conditions
Linn County, OR · surrounding county from lake location
Severe Drought
Severe drought conditions are present.
Severity
Weekly trend
Stable
Compared with last week
Official drought
Yes
100% of the watershed is currently classified as official drought (D1+).
Expected impacts
- Lower stream inflows
- Lake levels may decline faster
- Vegetation is becoming drier
- Minor increase in wildfire risk
U.S. Drought Monitor · map date Sep 8, 2026. Updated weekly. droughtmonitor.unl.eduView drought map for Linn County, OR
Key Facts
Managing authority
Waterbody / project type
Official purposes
Current-level source
Project / NID identifier
Dam / watershed (NID design values)
Static design values from a confidently matched National Inventory of Dams record — not live gage readings.
- Normal storage
- 160,000 acre-ft
- Max storage
- 430,000 acre-ft
- Surface area at normal pool
- 3,720 acres
- Drainage area
- 277 sq mi
- Spillway capacity (design)
- 110,000 cfs
- Dam structure
- Gravity · 378 ft high · completed 1967
- Hazard classification
- High
- Safety & inspection
- last inspection Jun 11, 2025 · EAP yes
National Inventory of Dams · matched record: Green Peter Dam (OR00010)
How this lake is operated
- Documented project purposes (National Inventory of Dams): Flood Risk Reduction, Hydroelectric, Irrigation, Navigation, Other, Recreation.
Why the level can change
General factors for reservoirs like this
These are common influences for this type of lake. They do not identify the cause of a specific current change unless an operator update confirms it.
Rainfall & inflows
Rain and upstream river inflows can raise reservoir levels, especially after storms.
Downstream releases
When an operator releases water through a dam, reservoir storage can fall and downstream flows can rise.
Flood-risk operations
Some projects store or release water under flood-risk rules when conditions require it.
Water supply
Some reservoirs support municipal, industrial, irrigation, or regional water-supply needs.
Hydropower
Hydropower projects may pass water through turbines when generating electricity.
Seasonal weather
Dry periods, heat, evaporation, and seasonal rainfall patterns can affect storage over weeks and months.
Current data source
Managing authority: U.S. Army Corps of Engineers — Portland District
Observation source used by Lake Insights: USACE NWP District
Who manages the lake and who publishes the reading Lake Insights displays can differ. Lake Insights does not invent a source label from the managing authority alone.
General education
Shared background — not lake-specific facts
Lake Insights aggregates water level information from authoritative public sources such as the U.S. Army Corps of Engineers, NOAA, TVA, Bureau of Reclamation, power utilities, and other official lake operators. We preserve historical observations, calculate trends, and present lake conditions in a consistent format. For USACE NWP District, we link to the official source whenever it is available. Lake Insights does not predict future lake levels unless an official forecast has been published by the managing authority.
Common questions about Green Peter Reservoir
- Who manages Green Peter Reservoir?
- Green Peter Reservoir is managed by U.S. Army Corps of Engineers — Portland District. Lake Insights reports published gauge readings; it does not operate the waterbody.
- Where does Lake Insights get the level reading for Green Peter Reservoir?
- Lake Insights displays the latest available elevation for Green Peter Reservoir from USACE NWP District. The managing authority (U.S. Army Corps of Engineers — Portland District) may differ from the agency that publishes the observation used on this page.
- What are the documented purposes of Green Peter Reservoir?
- Documented purposes for Green Peter Reservoir (National Inventory of Dams): Flood Risk Reduction, Hydroelectric, Irrigation, Navigation, Other, Recreation.