Pinal County farmers will be most severely impacted when a water shortage is declared on Lake Mead.

If a three-state drought contingency plan (DCP) is approved, the Colorado River water on which many of these farmers rely would be completely cut in a Tier 1 shortage, when Lake Mead reaches 1,075 feet of elevation.

If the predictions are right, this first-ever shortage could be declared as early as 2020, a decade before farmers there were supposed to be off the water for good.

Somewhat overlooked in the discussion is the impact to cities when a shortage is declared under DCP – likely because most of the water on which cities rely is high-priority water that would not be cut in a Tier 1 shortage, regardless of whether DCP is in place.

NIA water could be completely cut

But metro Phoenix cities also have shares of what’s called Non-Indian Agricultural (NIA) water, which is one rung higher on the priority ladder than the so-called Ag Pool water used by Pinal County farmers.

That means if the drought contingency plan is approved, a portion of that NIA water would be cut when a Tier 1 shortage is declared (it wouldn’t be touched under the current guidelines, which were set in 2007).

And the cuts would become increasingly more severe as lake levels dip, nixing all NIA priority water in a Tier 3 shortage, which would be declared when Lake Mead reaches 1,025 feet (the 2007 guidelines just begin to cut NIA water in a Tier 3 shortage).

What’s more, cities say NIA water could be cut faster than predicted, because the estimates are based on the water ordered in 2015, when higher-priority uses were using less of their allocations than they are now. If that persists, it will leave less water for lower-priority uses in times of shortage.

Cities were relying on that water

That has big implications for cities, even if NIA water comprises only a portion of their total supply. Because a majority of Phoenix-area cities are already using NIA water for existing development. They also have spent millions of dollars to store it for later, as part of a requirement to prove cities have an assured 100-year water supply.

What’s more, only a little more than half of NIA water has been allocated to seven metro Phoenix cities and two tribes. The other 46 percent is tied up in pending or future settlements – water many cities had hoped to get their hands on to further shore up their long-term supplies.

If the water goes away – especially if it happens quicker than expected – cities will be scrambling to find other, more secure sources of water to store underground. And, well, let’s be frank: There aren’t a lot of those left.

That leads us to a thorny debate taking shape in the committee studying how to implement DCP in Arizona, which, essentially, is this:

Should cities use stored water to help farmers?

Some say that cities should be willing to help farmers by parting with some of the water they’ve stored underground. In their view, cities are hoarding water that, with proper compensation, could be used elsewhere.

But cities say they need that water to prove they have an assured 100-year water supply. They say it’s short-sighted to trade water they have spent years and millions of dollars acquiring, particularly if the NIA water they were counting on to shore up their supplies may be severely trimmed, if not completely lost.

That doesn't mean cities are balking at DCP. They agree it needs to be signed, even if it cuts deeply into NIA water. They also say they want to help farmers – but by allowing cities to keep the water they've already stored and encouraging them to store future water in Pinal County, in return for storage credits closer to home.

It'll be interesting to see how that debate plays out.

Either way we go, it's a Band-Aid

But the core takeaway is that no one is going to get everything they want, and no matter which direction we go, it will be a Band-Aid. Because that’s what DCP ultimately is: A Band-Aid to keep Lake Mead from tanking, requiring even more painful cuts from everyone.

Propping farmers up until 2026 doesn't solve the deeper question about how Pinal County agriculture – not to mention the builders that rely on farmers' water rights to fuel residential growth – will respond to a future with no Lake Mead water. We can't move supplies indefinitely simply to preserve the status quo.

Nor will it help cities find a replacement for NIA water if that pool suddenly disappears. They are going to have to get even more creative to secure water for the future.

The best we can hope for is that this process builds the goodwill and working relationships necessary to keep tackling these thorny issues long after DCP is in place.

Reach Allhands at joanna.allhands@arizonarepublic.com.

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