In study session Tuesday, the Tucson City Council will discuss setting criteria for deciding whom it should allow to connect to an existing Central Arizona Project pipeline -- Community Water Co. of Green Valley, Farmers Investment Co., or both. We're reporting on that issue in today's print edition, but we'd like to list some of the potential criteria here.

Both companies want to build their own pipelines to take CAP water down to the Sahuarita-Green Valley area. At first, they would only bring their own CAP-contracted water down their 36-inch diameter pipelines. Eventually, however, they both say they want to take others' CAP supplies down there, to reduce the groundwater pumping that has slowly drained the area's aquifer.

Being able to hook into the existing pipeline, which runs 2.3 miles from the CAP's Pima Mine Road terminus east to the Pima Mine Road recharge facility, would greatly speed both companies ability to get their own pipelines built farther south.

A complicating factor is that Community Water's pipeline is being financed by Augusta Resource, Rosemont Copper's Canadian parent company, and some of its CAP water will be used to replenish groundwater that Rosemont Copper will pump for its mine in the Santa Rita Mountains. That's making it a controversial project, although Community Water Co. says this pipeline will offer the region a lot of benefits far beyond those for the mining company.

Here are some of the criteria that the Tucson City Manager's Office suggests the council consider Tuesday. The city staff made no recommendations.

1)The project positively contributes to the regional goal of bringing the Tucson Active Management Area -- a state-run water management area -- into safe yield, or the balancing of groundwater pumping with recharge.

2)The project must provide a net gain of water to the Tucson basin in the Tucson Active Management Area.

3)A project can' t degrade groundwater quality.

4)A project's manager and operator must show it's financially able to build and and operate its pipeline.

5)All necessary permits for the pipeline must be in hand.

6)The project should be scheduled for completion in less than a year.

7)A project connecting to this pipeline must show it won't harm operations of the Pima Mine Road recharge project.

8)A third party's use of the pipeline -- a party besides the one building and operating it -- shall be limited to its current CAP allocation.

That's it. The real struggle will come when the city adopts these or other criteria, and FICO and Community Water Co. will have to prove that they meet them.