TUCSON, AZ (November 24, 2025) — Arizona is undertaking a landmark water infrastructure effort: the Central Arizona Project (CAP) and the Salt River Project (SRP), two of the state’s largest water systems, will be physically connected via a new interconnection facility, projected to cost around $250 million, with a target completion in 2028.
WHAT’S BEING BUILT AND WHY
- CAP delivers Colorado River water over a long aqueduct system (300+ miles) to about 80% of Arizona’s population.
- SRP draws from the Salt & Verde Rivers in the Phoenix region and serves the greater metro area.
- The new facility — the “SRP–CAP Interconnection Facility” (SCIF) — will allow bidirectional flow between the two systems.
- Connecting the systems enhances statewide flexibility and resilience amid long‑term drought and Colorado River shortages.
SIGNIFICANCE FOR ARIZONA’S WATER FUTURE
- Improves resilience and redundancy if one system faces cuts or constraints.
- Provides operational flexibility for managing flows, exchanges, and shortages.
- Supports long‑term planning as climate pressures reshape water availability.
- Estimated cost: $250M; anticipated completion around 2028.
KEY CAVEATS & NEXT STEPS
- Depends partly on upcoming negotiations over the Colorado River operating guidelines.
- Engineering, environmental review, and permitting will be complex.
- Budgets and timelines may evolve.
- Cities and utilities will evaluate cost, reliability, and operational impacts.
IMPLICATIONS FOR TUCSON & PIMA COUNTY
- Enhances statewide water‑system stability, indirectly supporting Tucson’s planning.
- Reduces risk sensitivity for development and long‑term growth models.
- Strengthens internal system flexibility that could ease regional stressors.
In brief, Arizona’s CAP–SRP interconnection represents a significant step toward a more integrated statewide water‑delivery network. As drought persists and river‑system pressures grow, this infrastructure investment is designed to increase flexibility, redundancy, and long‑term reliability. For the Tucson region’s real‑estate and planning sectors, it’s a significant development with wide‑ranging implications for future growth and water‑security strategy.
For more information, go to Central Arizona Project - CAP and Where your water comes from in the Phoenix metro area | SRP.