The CAP system moves water 336 miles, pumping it uphill nearly 3,000 feet along its journey. Water is heavy, and so power is a critical component of moving the water to 80 percent of the state’s population in central and southern Arizona.

CAP’s power team secures power to meet the water utility’s needs and arranges for the power to be transmitted to specific locations at certain times. The transmission of power is a critical component to CAP’s power operations. Jeff Ritter, CAP’s Power Programs manager, answers a few key questions about transmission systems, the backbone of a power grid.

So how does power get to the pump load?

• Jeff: Power is generated at power plants and then travels through various substations and over transmission lines before eventually reaching CAP pumping plants. At this point it is used to operate our pumps and move water through the canal.

What is the importance of where power lines are in relation to canal?

• Jeff: Transmission lines routing power to CAP ultimately terminate in a substation at each pumping plant. In some cases, these lines are in close proximity to the canal for long stretches, while in others, they run all over the state in order to satisfy our energy needs.

Where does power come from (in-state or out of state)?

• Jeff: In 2022 and 2023, the vast majority of energy used by CAP came from power resources within the state of Arizona. A combination of nuclear, solar, hydro, and natural gas comprised the bulk of the energy need.

Whose job is it to maintain transmission lines?

• Jeff:  CAP does not maintain transmission lines.  We have long-term contracts with other utilities to maintain the lines that we utilize when moving energy to our plants.

Are there different types of transmission lines?

• Jeff:  There are many different types of transmission lines.  From a more technical perspective, they will vary widely in terms of electrical, mechanical, and structural parameters.  More generally, the voltage class of transmission lines is a distinguishing feature.  Typically the higher the voltage, the greater the distance between lines that are on the same tower.

In addition to this complex transmission system, CAP has developed a diversified power portfolio, which includes renewable supplies and a combination of long-term and market purchases.  Learn more about CAP’s power portfolio.