Cities want to recycle water. Here’s why that’s bad for the Great Salt Lake.

Utah’s booming growth continues to take a toll on water supplies.

(Francisco Kjolseth | The Salt Lake Tribune) Hydrologists place groundwater monitoring devices near an amphibious vehicle at Farmington Bay in a channel widen for treated discharge from the Central Davis Sewer District plant, pictured Thursday, Nov. 2, 2022. Treated effluent is some of the only water guaranteed to flow to the shrinking lake, but cities are eyeing it for reuse.

Cities and public utilities have filed a deluge of water reuse applications to get ahead of a bill meant to keep their treated wastewater flowing to the Great Salt Lake.

Here’s why cities say they need recycled wastewater, and why that’s a concern for the imperiled lake.

[Related: Flurry of water reuse claims threatens to take more water from Great Salt Lake]

The dilemma cities face

Most of the Great Salt Lake basin’s largest wastewater treatment plants are located near the shores of the Great Salt Lake or Utah Lake, which are connected via the Jordan River. Those facilities discharge cleaned water into canals or rivers that flow to the lakes. The facilities have had to upgrade their treatment standards, sometimes at great cost, to prevent harmful algal blooms.

But as growth and drought put pressure on communities in the basin, they’re eyeing their cleaner wastewater as a future source to meet outdoor irrigation demands. In some cases, cities plan to treat it to a level where it can be used indoors as well.

Why recycling wastewater could be bad for the Great Salt Lake

As of today, treated effluent is some of the only water guaranteed to reach Utah’s salty inland sea. Rep. Casey Snider, R-Paradise, warned during last winter’s legislative session that if every municipality in the basin recycled its treated wastewater to the extent it stops flowing downstream, the Great Salt Lake could drop by another 10 feet — a likely disastrous scenario.

How the proposed solution may have backfired

Snider persuaded lawmakers to pass HB349 in March. The bill prevents the Utah Division of Water Rights from approving any new reuse applications for wastewater that would have otherwise been discharged to the Great Salt Lake or its tributary rivers. The bill went into effect on Nov. 1.

In the months before that deadline, the division had 45 water reuse applications land on its desk. All but one are in the Great Salt Lake’s watershed. By comparison, in the nearly 25 years before 2023, it had only seen 25 applications combined statewide.

Many of the proposals are incomplete, lacking clear plans or calculations of how much water they’ll deplete from the environment and, ultimately, the lake. Community leaders acknowledge HB349 created pressure for them to develop reuse plans quickly before the opportunity closed.

Why communities say they need to reuse water

Some cities say they need the recycled water to become more resilient to drought and keep pace with ballooning growth. Certain applicants claim they’re entitled to deplete the full amount allocated under their water rights, and recycling allows them to do that. But others are worried about over-tapped aquifers. They want to reuse treated effluent so they stop drawing down groundwater which, they note, is also connected to the Great Salt Lake’s hydrology.

Over-pumped aquifers across the nation have seen salty water encroach from the ocean or briny groundwater before. Some worry the Great Salt Lake’s salty water could seep into water supplies if the water table continues to drop.

Will the state reject its flood of reuse applications?

Before any of the water recycling projects can proceed, they’ll need to be approved by the state engineer, who helms the Division of Water Rights. Legal experts say she has tools at her disposal to deny reuse applications and protecting the Great Salt Lake is one valid reason to reject them. To learn more, and to see a spreadsheet of which cities submitted proposals, read our story detailing the flurry of water reuse plans filed this year.

Great Salt Lake Collaborative Manager Heather May contributed to this report.

This article is published through the Great Salt Lake Collaborative, a solutions journalism initiative that partners news, education and media organizations to help inform people about the plight of the Great Salt Lake—and what can be done to make a difference before it is too late. Read all of our stories at greatsaltlakenews.org.