Current USBR operations without TUCPs A management strategy in the COEQWAL scenario library
Regulations and policies that govern Central Valley water operations are continually evolving, meaning that the definition of “current” operations depends on the time window in which you make such a designation. This strategy represents a variation of USBR's 2024 long-term operations plan (Alternative 2 version 1), rather than the DWR operating rules encapsulated in the “Current Operations” that chronologically preceded it. This scenario is run with the same hydrology and the same 2020 land use as in “Current Operations” but does not activate TUCP actions. Two fields differ from current operations: the biological-opinion rules and the TUCP setting.
This brief describes “current USBR operations without TUCPs”, one of 28 management strategies in the COEQWAL scenario library. Each strategy is simulated once under each of five hydroclimates; the references note at the end of this brief lists the model runs.
§2 What this strategy changes
The strategy replaces the operating rules of current operations with those of USBR's 2024 final Long-Term Operations (LTO) scenario Alt2 version 1 — a variation on USBR's proposed-action alternatives from the consultation with fisheries agencies that concluded in December 2024. TUCP actions are not active in this configuration, as in the source study.
Actions in this configuration that differ from the DWR-based current operations include, but are not limited to, modified Shasta storage rules and CVP allocation rules oriented toward winter-run Chinook salmon. The companion strategy Current USBR operations runs the same package with TUCP actions activated; the pair isolates the TUCP switch within the USBR ruleset.
§3 The configuration in detail
The table compares the eight operational fields that define this strategy against current operations — the strategy that represents existing operational rules, recent (2020) land use, and TUCPs. Rows that match current operations are shown in light gray; rows that differ are highlighted.
| Aspect | Current operations | This strategy |
|---|---|---|
| TUCP actions | Active | Not active |
| SGMA actions | None | None |
| Land use | 2020 LandIQ | 2020 LandIQ |
| Delta regulations | Standard | Standard |
| BiOps | 2019 / 2020 ITP | 2024 USBR Alt2v1 |
| Infrastructure | Standard | Standard |
| Flows | Standard | Standard |
| Allocation / priorities | Standard | Standard |
§4 Lineage and source
The model code and input structure were taken from USBR's 2024 final Long-Term Operations scenario Alt2v1. The COEQWAL team replaced the original USBR hydrology (which reflected a climate centered on 2022) with DWR's adjusted historical dataset and updated the crop maps used to estimate irrigation demands to the 2020 LandIQ dataset. TUCP actions remain deactivated, as in the source study. The internal hydrologic forecasting mechanism was not modified and follows the version used in the source study from USBR. The CalSim model files for this strategy are referenced by the run IDs in the references note at the end of this brief.
§6 What this doesn't say
This brief describes a scenario representation in CalSim, not a real-world policy proposal or implementation plan. The strategy as modeled may not capture all details necessary to support direct translation to actual operations. The brief does not predict, evaluate, or recommend any outcome — it describes what the scenario changes about CalSim's representation of the system. For what the model produces under this strategy, see the result briefs referenced in §7.
§7 See results for this strategy
To see modeled outcomes for the current-operations family across all nine key outcomes at the reference hydroclimate, see the BASELINES brief.
To see outcomes at a specific location of interest, see the relevant LOI briefs — particularly those for Shasta reservoir, Sacramento River locations, and the export service areas.
References — model runs
Each strategy is simulated once under each of five hydroclimates. The table lists the model run behind this strategy and the current-operations run it is compared against, for each hydroclimate, so any reader can trace this page to specific CalSim runs.
| Hydroclimate | This strategy | Current operations |
|---|---|---|
| Historical hydroclimate (adjusted) | s0023 | s0020 |
| Moderate climate stress (EC-Earth3-Veg) | s0136 | s0134 |
| Moderate-high climate stress (cc50) | s0051 | s0047 |
| High climate stress (cc95) | s0060 | s0056 |
| Extreme climate stress (TaiESM1) | s0110 | s0108 |