Delta Conveyance Project A management strategy in the COEQWAL scenario library
This strategy represents the Delta Conveyance Project — a tunnel conveying water around the Delta with a 6,000 cfs North Delta Diversion capacity — using DWR's 2025 climate-adaptation model version as its base, adapted to the hydrology and land-use conditions shared across the COEQWAL library. It also carries the 2025 voluntary-agreement (“Healthy Rivers and Landscapes”) actions: additional flows and some rice-acreage fallowing in the Sacramento Valley.
This brief describes “Delta Conveyance Project”, 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 uses DWR's 2025 climate-adaptation scenario (model version CCA6) as its base. The sea-level-rise, land-use, and hydrology assumptions were adapted to match the conditions used across the COEQWAL library: DWR's adjusted historical hydrology, no sea-level rise, and the 2020 LandIQ land use.
The infrastructure change is the Delta Conveyance tunnel, with a North Delta Diversion capacity of 6,000 cfs, conveying water around the Delta.
Unlike earlier Delta Conveyance model versions, this configuration includes Voluntary Agreement — “Healthy Rivers and Landscapes” — actions, which previous DCP scenarios did not. These include additional flows and some rice-acreage fallowing in the Sacramento Valley, reflected in the land-use and flows fields of the configuration table.
§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 | Active |
| SGMA actions | None | None |
| Land use | 2020 LandIQ | 2020 LandIQ, adjusted for Sacramento Valley rice fallowing as part of the voluntary agreements |
| Delta regulations | Standard | Standard |
| BiOps | 2019 / 2020 ITP | Modified versions of 2019 / 2020 ITP |
| Infrastructure | Standard | Delta Conveyance Project (6,000 cfs North Delta Diversion capacity) |
| Flows | Standard | 2025 version of the voluntary agreements (VAs) as included by DWR |
| Allocation / priorities | Standard | Standard |
§4 Lineage and source
This strategy is built from DWR's publicly released 2025 climate-adaptation scenario CCA6, adapted by the COEQWAL team for comparability with the rest of the library (historical adjusted hydrology, no sea-level rise, 2020 LandIQ land use). 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 under this strategy across all nine key outcomes at the reference hydroclimate, see the The Delta as a living place theme brief.
To see outcomes at a specific location of interest, see the relevant LOI briefs — particularly those for Delta 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) | s0065 | s0020 |
| Moderate climate stress (EC-Earth3-Veg) | s0157 | s0134 |
| Moderate-high climate stress (cc50) | s0085 | s0047 |
| High climate stress (cc95) | s0105 | s0056 |
| Extreme climate stress (TaiESM1) | s0131 | s0108 |