MOAB — The aging wastewater treatment plant in Moab is violating state water quality standards and plagued by treatment capacity issues, forcing city leaders to say no to any more human waste being trucked in from national parks or Bureau of Land Management campgrounds.

The interim measure was one of three steps the Moab City Council agreed to pursue after a special meeting Tuesday, stopping short of an overall moratorium on any new sewage connections.

"We are hopeful these interim measures will help get us into compliance," said Moab City Manager David Everitt.

The city will also have plant managers install a new filter and chemical treatment to try to counter violations of key effluent standards.

Everitt said the plant is not struggling with what comes into the facility, taking in about 1 million gallons of day with a capacity of 1.5 millions a day. Rather, he said, the amount of solids the facility has to treat before it can discharge to the Colorado River and remain within water quality standards has put the plant at its limit of treatment capacity.

"The issue is what comes out. We are exceeding two regulatory limits on a periodic basis," he said.

Everitt said about 10 percent of what comes into the plant comes from national parks and pumped toilets on BLM campsites.

A technical report presented to city leaders Tuesday detailed that up to 10 septage truck deliveries are made to the plant each week during the summer, containing waste from nearby state parks, national parks, campgrounds, isolated homes and other facilities. In the winter, the report notes that there is substantially less septage delivered during those months when the tourism season begins to abate.

Moab's plant is routinely above certain monthly effluent concentrations set by the state, and in July 2013 it was 1,200 pounds over its usual summertime inflow.

A new $12.4 million wastewater treatment plant is under design and on an accelerated schedule to be completed within 18 to 20 months. An environmental assessment has been performed due to a proposed new location and is up for review through mid-November.

A draft Utah Division of Water Quality document notes that while the city of Moab has received violations for wastewater discharges that violate standards — including for E. coli — the flows of the Colorado River are such that they overwhelm what comes in from the plant, so there are no contamination issues.

"We believe there have been no impacts because of the flows," said Leah Ann Lamb, assistant director of the water quality division. "We don't want anyone going over their permit limits, so we are thrilled that they have a new plant in the works."

The aging plant, built in the 1950s, had upgrades in 1983 and 1996, but it hasn't been able to keep up with population growth and pressure from tourism.

"The tourism season has become longer and the number of visitors has increased. This is a pattern that will continue into the future. It was also shown that the facility receives a greater amount of hauled waste (septage) than previously thought, which will also continue to grow as tourism increases," the division's draft document notes.

Kate Cannon, superintendent of Arches and Canyonlands national parks, said the park system is exploring its options. The park also handles waste disposal services for some BLM campground toilets, but the Dead Horse State Park is under a different contract.

"This is just one example of the struggles that occur with the growth in visitation that we are seeing," she said. "We are working hard to find solutions."

Everitt said there may be other regional wastewater treatment plants that can take the park sewage, such as Price or Blanding, but nothing has been settled yet.

A moratorium on any new connections would halt a bustling tourism economy that has several new large hotels and housing developments scheduled to come online.

City leaders heard pleas that single, primary housing developments be exempt from any moratorium, but that action won't be taken up until the City Council's regular meeting scheduled next week.

Waste management issues are also causing a stink for Zion National Park officials, who are seeing toilets designed for 50 visits a day handling hundreds of encounters.

In September, the park conducted an aerial operation dubbed "helipoo" to remove and then replace toilets atop Scout Lookout on the Angels Landing trail.

Proliferation of human waste at the Narrows has also been attributed to an E. coli contamination of the Virgin River.

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