The Colorado River Abundance Act: Long-Term Insurance
Building new water is the Southwest's best long-run play. But it takes 15 to 20 years to come into service. So it cannot rescue the near term.
The Blue Ribbon Coalition proposed the Colorado River Abundance Act in late 2026. It is not a plan to change the rules for releasing water. It is a plan to build new water supply. The idea is simple. Build desalination plants that turn ocean water into drinking water. Pipe that water into the Colorado River system. Deliver 2 to 7 million acre-feet each year to Lake Mead or Lower Basin users. That new water replaces some of what Powell has to release. So Powell stays higher. Same lake. More water. Fewer releases needed.
This is the long-term partner to rule reform. Post-2026 rules change how we release the water we have. The Abundance Act changes how much water the system has.
What the Act proposes
The Act sets up a Colorado River project to add new water in three stages. It also covers funding, public-private partnerships, and faster permits to speed up building:
- Phase 1 (2 MAF/yr): The first plants come into service by 2045. They deliver 2 million acre-feet per year. This matches the size of Israel's entire desalination fleet.
- Realistic buildout (3 MAF/yr): A step-by-step expansion through 2065. This is enough to close the Lower Basin's yearly shortfall.
- Full buildout (7 MAF/yr): The full vision. 7 MAF/yr in service by 2055. That is about 10-13% of today's global desalination capacity. All on one coast.
Our simulator adds each level on top of whatever operating rule the user picks. For the scorecards below, we used the current 2007 Guidelines as the rule baseline. That way we can see the effect of the new water on its own.
New water flows into Mead and the Lower Basin. That cuts the releases Powell has to make. All three cases use the 2007 Guidelines as the operating rule.
The scorecards
Same stress test as every other plan we evaluate: last-10-years inflow, 2,000 Monte Carlo iterations, 40-year horizon.
| Scenario | 10 yr | 20 yr | 40 yr | 40 yr floor |
|---|---|---|---|---|
| 2007 Guidelines (baseline) | 3544.4 ft | 3547.8 ft | 3534.9 ft | 3370 ft |
| + Phase 1 (2 MAF/yr) | 3545.7 ft | 3558.5 ft | 3605.7 ft | 3370 ft |
| + Realistic (3 MAF/yr) | 3544.3 ft | 3557.1 ft | 3603.5 ft | 3370 ft |
| + Full (7 MAF/yr) | 3544.2 ft | 3581.4 ft | 3606.8 ft | 3370 ft |
What the data shows
1. In the first decade, new water does almost nothing.
The 10-year medians are barely different from the baseline (difference <1 ft). The model is not broken. This is the timeline. The first plants do not come into service until 2045 at the earliest. Before then, the Act gives the system nothing new. This is the honest cost of big, slow projects.
2. By 20 years, the effect starts to show.
Phase 1 adds 11 ft to the 20-year median. Realistic adds 9 ft. Full adds 34 ft. Not huge yet. But the line is bending up.
3. By 40 years, the effect is large.
Full buildout lifts the 40-year median from 3534.9 ft to 3606.8 ft. That is about 72 feet of added elevation. All of it comes from making new water. Even the Realistic case adds ~69 feet. This is the case for new water as long-term insurance against rising demand.
4. The worst-case floor is still dead pool.
Every new-water scenario's worst 10% case still hits 3,370 ft (dead pool). Why? Because it takes 15-20 years to build these plants. In the worst 10% of futures — long runs of dry years starting soon — the lake can reach dead pool before the new plants deliver any water. New water is a long-run lift. It is not a short-run rescue.
Strengths
- Works with any operating rule. New water stacks on top of the 2007 Guidelines, any DEIS option, or whatever comes next. No conflict with other reform.
- Grows with demand. The Southwest's population keeps growing. Every other plan divides a shrinking pie. This plan builds a bigger pie.
- Protects Compact and Treaty deals. The Act is clear that this new water is extra. It does not change Mexico's Treaty share. It does not shift duties between the Upper and Lower Basins.
- Long-run elevation lift is real. 40-year medians above 3,600 ft in the Realistic and Full cases, even with last-decade stressed inflows.
Weaknesses
- Timeline. The first plants come into service around 2045. The Carlsbad desal plant (50,000 AF/yr) took about 15 years from idea to operation. 7 MAF/yr is about 140 Carlsbads worth of plants. No coast has ever built at that scale.
- Cost. New water runs about $2,500 to $4,500 per acre-foot delivered to Lake Mead or Powell. Today's Colorado River water costs about $270/AF. The cost is worth it if the other choice is an empty reservoir. But the gap is real.
- Energy use. Full buildout at 7 MAF/yr would need 42 to 63 TWh/yr. That is 8 to 12% of the Southwest's total power. It is about 50% of Arizona's total power. The Act calls for new renewable plants. Whether we can build them fast enough is an open question.
- Cannot save the near term. For the next 15-20 years, the Act adds nothing to Powell's elevation. Only rule reform can help in that window.
Verdict
The Abundance Act is a long-term play. And a strong one. It does not compete with rule reform. It partners with it. The right path is both. Pick the best operating rule for the post-2026 period. Also support the Abundance Act for long-run infrastructure. The operating rule protects the lake in the near term. New water keeps the system ahead of rising demand in the long term.
If you have to pick one, pick the operating rule. The simulations are clear. New water alone cannot save the worst-case futures. But supporting both is better than picking just one. The Abundance Act is the most hopeful vision on the table for the Southwest's water future. And the math works. With enough time and money, we can build our way to a reservoir that refills.
Read the head-to-head verdict on which operating rule to pair this with, or start from the real problem isn't drought — it's math.