When the land wouldn’t support septic tanks, a Provo Canyon subdivision tries its own mini sewer system

But critics suspect “solution” could enable further building in a place that can’t sustain it.

(Brian Maffly | The Salt Lake Tribune) This wastewater equipment, photographed on March 18, 2022, is to be installed at the Canyon Meadows subdivision in Wasatch County.

Provo Canyon • Tucked into a ravine near the top of Provo Canyon is the Canyon Meadows subdivision, where new home building came to a standstill years ago.

Lawsuits and bankruptcies attest to the difficulties that plagued past developers who struggled and failed to build here. Canyon Meadows is too far from any municipal sewer system to tie into, leaving septic as the only option for treating sewage. But most of the developments’ 84 lots can’t pass the requirements for septic systems.

Now the subdivision’s latest developer has hit upon a potential — though expensive — solution that would enable another 55 homes to be built in the scenic spot under Deer Creek Dam with views of iconic Mount Timpanogos. With Wasatch County’s help, Scott Lybbert is building a mini sewer system and wastewater processing facility.

“This is far superior than the septic systems the current homeowners are using. If we are concerned about protecting the Provo River, this system is a better option,” Lybbert says. “Instead of having individual systems at each home that aren’t being managed and monitored, we have these large septic tanks.”

The developer’s plan could demonstrate the viability of on-site treatment, officially known as “Large Underground Wastewater Disposal Systems,” for addressing Utah’s growing problem of failing septic systems, especially in rural subdivisions.

But some of Canyon Meadows’ existing homeowners like Tracy Hall are skeptical.

“See that seepage there,” he says during a recent tour of the subdivision, pointing to a boggy meadow below the homes and unbuilt lots. “Water is at the surface and the sewer line has to go through that.”

A retired chemist with many patents to his credit, Hall lives in the first home built in the subdivision and his father-in-law was Canyon Meadows’ initial developer.

(Brian Maffly | The Salt Lake Tribune) Provo Canyon resident Tracy Halls looks over the Canyon Meadows subdivision in Wasatch County on March 18, 2022.

Various components of the wastewater system are arrayed on the ground, soon to be embedded on a bluff above the Provo River. Four maroon 25,000-gallon underground tanks and four large boxes containing filtration media sit next to the system’s key feature, a 3-acre leach field where drip irrigation lines are to distribute the effluents.

Lybbert’s plan is to bury 2.5 miles of green 8-inch PVC sewer lines under the subdivision’s dirt lanes that would direct homes’ wastewater to the big tanks and filtration equipment manufactured by Orenco, a firm specializing in on-site wastewater treatments systems. Also sitting on the ground are dozens of 4-foot-diameter concrete collars and vaults that will tie each lot into the main sewer line and miles of drip irrigation tubes.

No homeowners are being forced to hook into the system, but it will be there as a backup if they change their mind or if their septic systems fail, according to the developer. Lybbert is fronting the more than $2 million cost and will cover homeowners’ share if they sign on now. If they wait, he will insist they pay a prorated share, or about $25,000 per home, he said.

With wastewater treatment online, Lybbert would then be able to build or sell the remaining lots. Once operable, the system will be taken over by the newly formed Owl’s Nest Special Service District, which will bill the lot owners.

Under the district’s rate design, homeowners can expect to pay $55 a month. That’s about double what Salt Lake City residents pay, but far less than the $100 a month levied in some rural Utah communities, such as Millville, that are switching from septic to sewers.

According to Hall, however, few of Canyon Meadows’ existing 29 homeowners are excited about the idea of abandoning their functional septic systems they spent several thousands of dollars installing and paying monthly sewer fees. Hall has no intention of hooking his home into the sewer.

This is a dynamic playing out across Utah’s rural areas — especially those near population centers but not close enough to easily connect to existing wastewater infrastructure — where septic-served homeowners are being asked to pony up, often with taxpayer subsidies, for a sewer system. These huge investments could ultimately facilitate even more development in once-quiet places, like Bear Lake, Weber Canyon, Upper Ogden Valley, Cedar Mountain and Provo Canyon.

Septic systems are proliferating across the state as more people develop residential lots in rural areas. And this spells trouble for groundwater because these septic fields are becoming too dense in some communities and many systems are failing, injecting nutrient-loaded effluents into aquifers and creeks, according to Erica Gaddis, former director of the Utah Division of Water Quality.

According to data compiled by DWQ, 127,000 Utah homes rely on septic, covering 12% of the state’s population. These systems are approved by local health departments, while Gaddis’ agency is responsible for approving and overseeing larger systems that process more than 5,000 gallons a day.

The division has authorized 125 such systems, 20 of which were approved in the last five years, including the one to be installed at Canyon Meadows. Gaddis characterized these facilities as large communal septic systems, which offer some advantages over the individual septic systems approved by the hundreds by local health departments.

“I get why homeowners are frustrated with this particular situation. I get it, but these larger systems are part of the solution because they do allow us to have a management district which we don’t have in those septic areas,” Gaddis said last month shortly before she left DWQ. “You’ve got someone that’s paying attention, that’s maintaining it, that’s making sure the minimum requirements are being met, so that’s good.”

In other words, if something goes wrong, it can be fixed right away, while a home’s failing septic system can discharge raw sewage for years without anyone noticing.

Gaddis suspects such a scenario has been unfolding in Emigration Canyon, a township of about 700 homes just outside Salt Lake City. The entire canyon has been on septic systems for decades and the evidence of failing systems is now apparent in Emigration Creek, which flows out of the canyon past or through parks, Hogle Zoo and backyards. The township is now under pressure from the state to sewer the entire canyon, but the cost would be in the tens of millions.

In this light, Lybbert’s plan for Canyon Meadows might seem like the right thing to do.

(Brian Maffly | The Salt Lake Tribune) This wastewater equipment, photographed March 18, 2022, is to be installed at the Canyon Meadows subdivision in Wasatch County.

Richard Jex, a former Wasatch County health inspector whom Lybbert hired to design his system, believes on-site treatment in many instances is the better option in terms of cost and environmental benefits.

“There’s some pressures and decisions made that are motivated to drive sewer at enormous costs,” Jex says. “These solutions like what we’re doing in Canyon Meadows, they are expensive, but they’re not as expensive as sewer.”

Hall sees the project, however, as a way to cram as many homes as possible on land that is not able to absorb septic effluents without endangering public health or the Provo River, a crucial water source for Utah and Salt Lake counties. The river also feeds Utah Lake, which suffers from seasonal algal blooms, fueled in part by nutrients associated with wastewater.

But worse, according to Hall, the system would concentrate the subdivision’s entire wastewater load onto a 3-acre leach field perched about a quarter-mile above the Provo River. And the sewer lines will have to be buried up to 20 feet deep in places to maintain gravity feed and avoid contact with culinary water lines. Hall worries the gravel beds that will hold these lines could wind up directing groundwater right into the leach field, further saturating the soil.

The leach field is situated just above U.S. 189 where a wildlife underpass has been installed. Hall is concerned the slope would push any overflow from the drain field through that underpass, and from there it is a steep descent toward the river.

While such an event would be unlikely, the water discharged from the Orenco system would be clean enough that the environmental harm would be minimal, according to Jex.

“The first two tanks operate as primary treatment, very similar to a septic tank. Solids that settle will sink to the bottom, solids that float will lift to the top. The water in the center will move on to the next stage,” Jex says. “They’re trapped in the tank, they biologically digest and reduce in volume, but at some point, they’ll need to bring in a pump truck to pump some of those solids out.”

The main indicator for the level of contamination in wastewater is known as “biochemical oxygen demand,” or BOD, which signifies the amount of dissolved oxygen needed to decompose the organic matter contained in the wastewater. BOD values for raw wastewater run between 300 to 500 milligrams of oxygen were liter. Primary treatment provided in home septic systems cuts that by about half on average, although there is huge variability.

“With septic we can get that down to 180. That’s an improvement, but it’s still really dirty water,” Jex says. “By rule this technology, [discharged water] has to be below 25. And when you look at actual performance data, it’s often down below 10.”

In other words, it can exceed the standards for “secondary” treatment, on par with many municipal plants. While on-site treatment is technically a big septic system, Jex contends it is more akin to a sewer treatment plant.

“When you treat the water down to below 25 milligrams per liter, the potential to organically flood the soil is greatly reduced,” he says. The facility is approved to handle 33,000 gallons a day. Running a capacity, the wastewater would spend up to three days in the tank.

Such systems cannot remove nitrogen, the main pollutant of concern. But the effluent sees additional treatment after it is spread around the soil, where bacteria and plants further break down organic material, according to Jex.

“By going to the root zone, the plants eat the nitrogen because that’s a fertilizer for them,” he says. The effluent is to be released into the soil in 1-foot intervals, rotated through 16 zones.

“You put some water in a zone, then you rest it, and that gives more time for the bacteria to develop in the soil to further treat and let nature do its thing to clean that water and move that water off-site so that it’s a long-term solution,” Jex says. “It reduces the chances of failure.”

But Hall fears failure could be inevitable because the subdivision was sited on top of a slide area that has since been designated a “Hazardous Overlay Zone.” Under current standards, an 84-lot subdivision would not have been approved at this location, he claims.

Lybbert’s solution could wind up creating a bigger mess down the road by concentrating so much water in a sensitive piece of ground.

“This huge quantity of water not only threatens the stability of the highway, but it will render the sewer plant leach field inoperable, greatly increasing the risk of contamination of the Provo River,” Hall says. “The effluent from the 84 total planned homes almost certainly [would] turn the leach field into a mudslide.”

Editor’s note • This story is available to Salt Lake Tribune subscribers only. Thank you for supporting local journalism.