SALT LAKE CITY (AP) — A Utah Legislative audit has determined Washington County is expected to pay hundreds of millions of dollars to build and operate a proposed water pipeline.

The Salt Lake Tribune reported Wednesday that the state concluded the audit Tuesday saying the proposed Lake Powell pipeline would require a large fee, rate and tax increases and cost about $1.4 billion over the next 50 years.

Officials say the 140-mile (225-kilometer) line would divert water from the Colorado River across southern Utah each year to the Sand Hallow Reservoir to supply the St. George metro area.

Pipeline critics say the audit did not study whether the region needs the water, or if Utah’s cost estimates were reliable.

Officials say the project is undergoing reviews and expected to begin construction between 2023 and 2028.