Background

Since spring 2022, injunction and interim measures have been implemented in each sub-basin of the Upper Willamette system. To help inform the UBC IPA team’s data collection and analysis, this document includes timelines of which measures have been implemented at which projects and when. Data were compiled from biannual reports dated 2022-2024 (published in February and August of each year), up to and including February 2024.

This document includes implementation timelines in graphical and tabular formats.

Using this file: interpreting timeline graphics and accessing tables

Each graph in this webpage is interactive - you can hover over them, zoom in by highlighting the “zoom” area in the plot, and you can save each graphic with a download button.

The graphics are color-coded to represent the type of event reported in the biannual injunction reports. Colors of the events indicate the type of operation during that time, like so:

  • Regular operations in grey
    Some timelines do not include regular operations (e.g., refilling reservoirs between drawdown events) because these were not reported in biannual reports; other sites do report these “regular operations”.
  • Injunction and interim measures (IM) in blue
  • Flood risk management (FRM) interventions are in orange
  • Events are marked with black points

Underneath each graphic is an expandable box, formatted like this: “View the timeline in tabular format (click to expand)”. Clicking this will show you a table of the data in each graphic.

Timelines, data tables, and summaries of injunction and interim measures at each subbasin

North Santiam

  • BCL: Big Cliff re-regulating dam
  • DET: Detroit dam and reservoir
View the timeline in tabular format (click to expand)
Measure Project Start End Details
10/IM 6 BCL 2021-11-17 2021-11-24 Only during one of two involuntary spill events in Nov/Dec 2021 was there sufficient flow to split across gates
10/IM 6 BCL 2022-01-01 2022-12-31 “Spill split where possible”; limited effect
10/IM 6 BCL 2023-01-01 2023-12-31 Maximized efforts (maximized turbine operations and spreading spill) but did not prevent excessive TDG in some periods when LRO and URO operated at Detroit
10/IM 5 DET 2021-09-27 2021-10-13 Prepare for drawdown and prioritize non-turbine outlet during night
10/IM 5 DET 2021-10-13 2021-11-05 Limited success (hot/dry weather; low inflows/low reservoir elevations limit spillway operations to only 2 months instead of 4 which left lots of hot water; early drawdown and use of cold water storage in Detroit in the fall)
10/IM 5 DET 2021-11-05 2022-03-04 Upper RO prioritization at night
10/IM 5 DET 2022-10-09 2022-11-02 URO use for temp control
10/IM 5 DET 2022-11-02 2022-11-05 LRO use
10/IM 5 DET 2022-11-05 2023-04-14 Upper RO prioritization at night
10/IM 5 DET 2022-11-13 2022-11-17 LRO use
10/IM 5 DET 2023-09-28 2023-11-25 NA
10/IM 5 DET 2023-11-25 2023-12-03 LRO use
10/IM 5 DET 2023-12-03 2023-12-31 NA
10a/IM 7 DET 2022-04-08 2022-09-23 Spillway releases for temperature control
10a/IM 7 DET 2023-05-01 2023-08-14 Spillway + turbine to management downstream temperatures
Event DET 2021-09-21 2021-09-21 10/IM5 Revised due to conflict with 10a/7; temperature operations prioritized over downstream FP
Event DET 2022-11-17 2022-11-17 Reservoir deemed isothermal
Flood risk mgt. DET 2022-11-05 2022-11-17 URO use for flood risk mitigation
Flood risk mgt. DET 2023-12-03 2023-12-20 Atmospheric river; flood risk management
Reported regular ops. DET 2022-03-04 2022-04-08 Refilling
Reported regular ops. DET 2023-02-01 2023-05-01 Reservoir refilling

View summary descriptions of the injunction measures in the North Santiam (click to expand)


Detroit

  • Some interim measures (IM) were formally adopted in the injunction, and are sometimes referred to by their IM number or the injunction measure number. For example, at Detroit Dam, injunction measure 10 is a measure to adopt IMs 5, 6, and 7. Injunction measure 10 was revised and became 10(a) on Sept 21, 2021 due to conflicts between IM 5 and IM 7.
  • IM 5: Once the elevation of Detroit Reservoir is less than 100 feet over the turbine intakes during the fall drawdown and winter months, generally only operate the turbines at Detroit Dam during the day and prioritize a non-turbine outlet to pass flow at night (from dusk until dawn), generally with no turbine operation during that time.
  • IM 7: Through strategic use of the spillway, turbines, and regulating outlets at Detroit Dam, provide downstream fish passage in the spring and water temperature management throughout late spring and summer at Detroit and Big Cliff dams.
  • Injunction measure 10a: Draft Detroit Reservoir to elevation 1,465 feet or less by October 15, 2021 and then use Detroit Dam’s lower regulating outlets for temperature control purposes.

Big Cliff

  • IM 6: When the Corps is operating the spillway at Big Cliff Dam, operate multiple spillway gates to spread total flow across the spillway.

    • NOTE: The bi-annual reports do not record specific dates where multiple spillway gates were utilized at BCL to reduce TDG. It does sometimes report periods where the spillway was used at all, but this does not inform whether multiple gates were used to reduce TDG.

    • From the Feb. 2022 biannual report:

      The minimum gate opening for spill operations of each spill bay at Big Cliff is 0.75 feet. This equates to discharges that range from 770 cfs – 1130 cfs for reservoir elevations of 1182 ft. (min. conservation pool) and 1206 ft. (max. conservation pool), respectively. Under the lowest of reservoir elevations, flows cannot be spread between two bays until the total outflow is greater than 4740 cfs, which is the sum of the discharge from two spill bays at minimum gate opening plus powerhouse capacity [(770 cfs + 770 cfs = 1540 spill) + (3200 cfs powerhouse) = 4740 cfs total flow]. Under the highest reservoir elevations, flows cannot be spread between two bays until the total outflow is greater than 5070 cfs, which is the sum of the discharge from two spill bays at minimum gate opening plus powerhouse capacity [(1130 cfs + 1130 cfs = 2260 cfs spill) + 2810 cfs (powerhouse) = 5070 cfs (total flow)]. Without large flow conditions, spreading spill is limited at Big Cliff Dam.


For full details, see implementation plans on the Willamette Injunction website.

South Santiam

  • FOS: Foster dam and reservoir
  • GPR: Green Peter dam and reservoir

The timeline below does not show outplanting of Chinook salmon above Green Peter dam (injunction measure 11), which have occurred in summer 2022 and 2023.

View the timeline in tabular format (click to expand)
Measure Project Start End Details
13a FOS 2021-10-01 2021-12-15 Utilize spillway for improved passage
13a FOS 2022-10-01 2022-12-15 Nighttime spill and daytime generation
13a FOS 2023-10-01 2023-12-15 Nighttime spill and daytime generation
13b FOS 2022-02-01 2022-05-15 Delay refill and nighttime spill prioritization
13b FOS 2022-05-16 2022-06-15 Reservoir refill but continue nighttime spill prioritization
13b FOS 2022-06-16 2022-08-01 Summer fish weir operation
13b FOS 2023-01-01 2023-05-15 Delayed refill and downstream FP
13b FOS 2023-05-15 2023-06-15 Reservoir refill but continued nighttime spill prioritization
13b FOS 2023-06-16 2023-08-01 Summer fish weir operation
Reported regular ops. FOS 2022-09-06 2022-10-01 Gradual drawdown “just after labor day weekend” (estimated date)
Reported regular ops. FOS 2023-09-05 2023-10-01 Gradual drawdown “just after labor day weekend” (estimated date)
12a GPR 2022-03-17 2022-04-02 24/7 spill operation
12a GPR 2022-04-02 2022-04-15 Nighttime spill using 3ft gate (daytime spill 50cfs RO); no power gen
12a GPR 2022-04-16 2022-05-01 24/7 spill operation
12a GPR 2023-03-10 2023-06-06 24/7 spill operation; delay in start and extension of spill operation was to support release of bulk-marked fish that Cramer released into the reservoir in late May
12b GPR 2023-08-05 2023-11-02 Drawdown
12b GPR 2023-11-02 2023-12-16 Maintain at low pool
Flood risk mgt. GPR 2023-12-03 2023-12-16 Atmospheric river caused shift to flood risk management (subject to operational constraints (prioritizing return of FOS maximum authorized flood space; limiting outflow to 10k cfs; limiting GPR outflow to 4500 cfs maximum for RST))
Reported regular ops. GPR 2023-12-16 2023-12-31 Refill reservoir to minimum conservation

View summary descriptions of the injunction measures in the South Santiam (click to expand)


Foster

  • 13a: Draw down Foster Reservoir to elevation 620-625 feet by October 1 and operate the Foster Dam spillway, with limited turbine operation, from one hour before sunset to one-half hour after sunrise from October 1 through December 15.
  • 13b: Hold Foster Reservoir at minimum conservation pool (elevation 613 feet) and operate the Foster Dam spillway, with limited turbine operation, from one hour before sunset to one-half hour after sunrise from February 1 through May 15. Beginning May 16, refill Foster Reservoir, targeting full pool by Memorial Day Weekend, and operate the Foster Dam spillway, with limited turbine operation, from one hour before sunset to one-half hour after sunrise until June 15. Beginning June 16 through mid- to late-July, operate the Foster fish weir for downstream water temperature management.

Green Peter

  • 12a: Beginning in spring 2022, once Green Peter Reservoir reaches elevation 971 ft., spill continuously (24/7) until May 1 or for at least 30 days, whichever is longer. The implementation in 2023 was influenced by poor health of surrogate fish to be released during paired releases. This caused the Corps and NMFS to decide to continue operating 24/7 spill operations in 2023 versus testing continuous spill versus nighttime-only spill (as was planned with surrogate fish).
  • 12b: Conduct a fall drawdown of Green Peter Reservoir to a target elevation of 780 ft. by November 15 and hold at that elevation until December 15. Generally use the regulating outlets exclusively to pass flow once the reservoir is below minimum power pool (887 ft.).
  • 11: Outplanting above Green Peter (not shown in the graphic above, occurred in Summer 2022 and 2023).


For full details, see implementation plans on the Willamette Injunction website.

South-fork McKenzie

  • CGR: Cougar dam
View the timeline in tabular format (click to expand)
Measure Project Start End Details
14 CGR 2021-11-03 2021-12-22 Some station service was required to ensure no loss of FRM capability; in mid-Nov, reservoir elevation refilled due to storm and refilled to 1515 feet (from target of 1505 ft)
14 CGR 2022-10-04 2022-12-21 The large snowpack combined with late and un- seasonably heavy rains observed in the spring of 2022 resulted in quite a successful spring passage operation that allowed for an extended delayed refill
14 CGR 2023-11-02 2023-12-03 NA
15a CGR 2022-02-01 2022-05-27 NA
15a CGR 2023-02-01 2023-03-15 NA
15a CGR 2023-03-30 2023-05-25 During Mid-Apr there were difficulties holding reservoir low (one turbine was out); WTCT opened to provide additional surface downstream passage
Drawdown CGR 2023-03-15 2023-03-30 Further drawdown to 1520 ft
Flood risk mgt. CGR 2022-05-01 2022-05-01 High flow event
Flood risk mgt. CGR 2022-05-15 2022-05-15 High flow event
Flood risk mgt. CGR 2023-12-03 2024-03-01 NA
Night: RO/day: power gen. CGR 2021-12-22 2022-02-01 Nighttime RO; daytime generation
Reported regular ops. CGR 2022-02-01 2022-03-14 Drawdown
Reported regular ops. CGR 2022-05-27 2022-10-04 Reservoir refill for temperature controls; limited outflow except through the ROs
Reported regular ops. CGR 2023-05-25 2023-10-20 WCTC used for downstream temperature management and additional surface passage (in spring); stopped when elevation too low to operate WCTC

View summary descriptions of the injunction measures in the South Fork McKenzie (click to expand)


Cougar

  • 14: Conduct a fall drawdown of Cougar Reservoir to a target elevation of 1,505 feet by November 15 until December 15 and generally use the regulating outlets exclusively during that time to pass flow.
  • 15a: On December 16, initiate the refill of Cougar Reservoir to minimum conservation pool (elevation 1,532 feet) and hold until March 1. On March 1, begin drafting Cougar Reservoir to reach elevation 1,520 feet by April 1. Using adaptive management to determine the refill starting date, delay the refill of Cougar Reservoir from elevation 1,520 feet as long as possible while maintaining a high likelihood of reaching elevation 1,571 feet by July 1 to enable use of the water temperature control tower in late summer and fall. From December 16 through June 1, prioritize the regulating outlets at night to pass flows. In September, transition to the fall drawdown operation.


For full details, see implementation plans on the Willamette Injunction website.

Middle Fork

  • FCR: Fall Creek dam and reservoir
  • HCR: Hills Creek dam and reservoir
  • LOP: Lookout Point/Dexter dam and reservoir
View the timeline in tabular format (click to expand)
Measure Project Start End Details
19 FCR 2021-11-05 2022-01-16 Deep drawdown (early due to RST showing movement from the reservoir)
19 FCR 2022-10-20 2022-11-05 First deep drawdown
19 FCR 2022-12-01 2022-12-29 Second deep drawdown
19 FCR 2023-10-16 2023-10-22 End date estimated; First deep drawdown
19 FCR 2023-12-01 2024-01-09 Second “injunction” deep drawdown
20 FCR 2022-01-16 2022-04-15 Concluded to improve likelihood of reservoir refilling sufficiently to operate the Fall Creek AFF
20 FCR 2023-01-01 2023-05-05 Delayed refill; adverse consequences as reservoir did not fill enough
Flood risk mgt. FCR 2022-12-29 2023-01-01 Reservoir used to capture inflows during rain events
Reported regular ops. FCR 2022-03-15 2022-03-15 Refill to minimum conservation pool
Reported regular ops. FCR 2022-04-16 2022-10-20 Refill and operate AFF
Reported regular ops. FCR 2023-01-18 2023-01-18 Refill to 700 ft; otherwise delayed refill
Reported regular ops. FCR 2023-03-13 2023-03-13 Refill to 720 ft; otherwise delayed refill
Reported regular ops. FCR 2023-05-05 2023-10-16 Refill and operate AFF
8 HCR 2022-01-01 2022-03-01 Prioritize ROs at night (daytime generation) when elevation below 1460 ft.
8 HCR 2022-11-18 2022-12-29 Elevation below 1460 ft., turbines used during day and RO prioritization at night
8 HCR 2023-01-01 2023-04-12 Elevation below 1460 ft., turbines used during day and RO prioritization at night
8 HCR 2023-11-27 2023-12-03 Estimated start date; elevation below 1460 ft.
8 HCR 2023-12-21 2023-12-31 Prioritize ROs at night (daytime generation) when elevation below 1460 ft.
Event HCR 2022-07-14 2022-11-18 Due to repair work on turbines, RO operation begins early
Flood risk mgt. HCR 2022-12-29 2023-01-01 All flow to powerhouse due to Dec storm
Flood risk mgt. HCR 2023-12-03 2023-12-20 Flooding pushed above El 1460 ft.
16 LOP 2023-06-01 2023-07-13 Prepare for measure 16 (deep drawdown); ROs opened
16 LOP 2023-11-02 2023-12-16 Drawdown passage operations
17 LOP 2022-04-22 2022-05-23 Ungated continuous surface spill operation (exception May 6-9 when turbines were used to pass high flows caused by rain)
17 LOP 2022-05-23 2022-06-10 Spill gates replaced; nighttime spill operations
17 LOP 2022-06-14 2022-07-20 Nighttime spill operations concluded early due to downstream temperatures
17 LOP 2022-07-20 2022-08-27 Turbine use for temperature management
17 LOP 2022-08-27 2022-10-07 Concluded when LOP became isothermal
17 LOP 2023-04-15 2023-05-19 Ungated continuous surface spill operation
17 LOP 2023-05-19 2023-06-01 Spill gates replaced; nighttime spill operations
Event LOP 2022-12-01 2022-12-15 Unplanned PH outage
Event LOP 2023-07-13 2023-07-13 ROs opened to cool downstream water temperatures
Event LOP 2023-09-09 2023-09-09 Turbines turned off (elevation below power pool)
Flood risk mgt. LOP 2022-05-06 2022-05-09 Turbines used to pass high flows caused by high rain event
Flood risk mgt. LOP 2022-06-10 2022-06-14 Turbines used to pass high inflows for four days continuously
Flood risk mgt. LOP 2023-12-03 2023-12-31 Refilling of reservoir with high inflows (ending measure 16)

View summary descriptions of the injunction measures in the North Santiam (click to expand)


Hills Creek

  • 8/IM 20: Implement RO spill operations daily from 6-10 p.m. at Hills Creek Dam once the reservoir elevation is 50 feet or less above the regulating outlets in the fall through March 1.

Lookout Point/Dexter dams

  • 17: Use storage from Hills Creek Reservoir to begin refilling Lookout Point Reservoir in early March. Once Lookout Point Reservoir reaches elevation 890 ft., spill water over the spillways 24/7 for at least 30 days at both Lookout Point and Dexter dams while maintaining the elevation of Lookout Point Reservoir between 890-893 ft. During that time, generally do not operate the turbines at both projects, with limited exceptions. After that initial 30-day period, spill at night at both projects, with generation during the day, for as long as water is available and downstream conditions allow. Then manage Lookout Point Reservoir to achieve elevation 887.5 ft. by July 15, 2022 and operate the regulating outlets as needed to reduce downstream water temperatures when water temperatures downstream of Dexter Dam near 60 degrees.
  • 16: Annual Lookout Point Reservoir deep drawdown operation from November 15 through December 15.

Fall Creek

  • 19: Annual Fall Creek Reservoir deep drawdown operation similar to prior years but extend the dates from December 1 through January 15.
  • 20: On January 16, begin the refill of Fall Creek Reservoir to elevation 700 feet and hold at that elevation through March 15. On March 16, initiate the refill to reach elevation 728 feet by April 15 and maintain that elevation through May 15 unless additional refill is necessary to ensure operation of the Fall Creek Adult Fish Collection Facility through September 30. After May 15, refill the reservoir to the extent possible.


For full details, see implementation plans on the Willamette Injunction website.