Just look at the brouhaha bubbling over the proposed $800 million Lake Powell pipeline.

Water managers and local officials maintain booming southwestern Utah will thirst for that water - and sooner than many think.

"At current growth needs, we'll need the pipeline by 2020," Ron Thompson, director of the Washington County Conservancy District, told the Cedar City Area Chamber of Commerce on Thursday.

But environmentalists and others argue the 20-inch pipeline - funneling water 120 miles from Lake Powell in south-central Utah to Sand Hollow Reservoir in the state's southwest corner - will scar the public landscape and fuel growth that can't and shouldn't be sustained.

Officials with VisionDixie who've expressed skeptism of the project in the past did not return phone calls.

Either way, Thompson said, growth is coming, and securing water is the most crucial factor in supporting it.

If the pipeline is built, ThompÂson said it probably would be paid for by newcomers.

The Washington County cities that have agreed to buy that water plan to impose a $4,500 impact fee on new homes - with that tab rising 5 percent a year for 30 years.

That would bring in the $800 million needed for the project. In addition, Thompson said, construction and operating costs could be offset by pipeline-generated hydropower.

An engineering firm is conducting preliminary studies on the proposal, which is receiving $7 million a year from the state. That data will be turned over to the Bureau of Land Management to complete environmental studies.

Thompson said an acre-foot of water from the project would be worth about $5,000 - a competitive price in a county where the same amount of water in some locations goes for $40,000.

When asked if the pipeline would be included in the latest version of the Washington County land-use plan - a measure requiring congressional approval - Thompson said he doubted it.

"The federal government has nothing to do with this," he said. "We're not planning on using federal funds."

Scott Wilson, Central Iron County Water Conservancy District director, warned that Iron County's future is bleak unless it also can tap into the pipeline project and pump 36,000 acre-feet of water.

Right now, Iron County's aquifers are being drained faster than they can be replenished.

Wilson said state water officials have told him that of the five aquifers in the most trouble in Utah, three are in Iron County.

"It's scary," Wilson said. "We have to move forward with vision now."

He said Iron County has applied for water rights in the desert west of Cedar City for relief. But Beaver and Millard counties object. They also are eyeing that area for more water.

Kane County is expected to receive 10,000 acre-feet of water from the pipeline, which roughly would follow U.S. Highway 89 from Lake Powell to Sand Hollow, located 10 miles east of St. George.

mhavnes@sltrib.com