Editor’s note: This is the final installment of a three-part series on the history, ecology and future of Stansbury Lake.
With extensive weed growth, waterfowl and thousands of fish, it can be easy to forget the dynamic ecosystem in Stansbury Lake is meticulously maintained and monitored over the course of the year.
The man-made lake doesn’t have a natural source like a stream or river, which requires the water level to be adjusted throughout the year, according to Stansbury Park Service Agency manager Randall Flynn.
In the winter, the lake level is lowered to allow it to freeze closer to the bottom, Flynn said. This is detrimental to the sago pondweed cluttering the lake and helps prevent damage through heaving ice along the shoreline, he said.
Flynn said maintaining the level in the lake takes constant attention. This year, the lake was high by an inch or two through May after a wet spring, but he said that quickly changed due to heat and dryness.
The water level took a brief drop when it was discovered the pump at the Mill Pond had been damaged, likely by a lightning strike, when the water was needed, Flynn said.
“It’s a daily thing,” he said. “We have to monitor the level of the lake and try to make adjustments ahead of what we see coming.”
Management of the lake’s water level involves watching upcoming temperature and precipitation, to keep the water high enough it flows over the weir, Flynn said. Keeping the water flowing improves clarity and reduces the load of dissolved solids in the lake, he said.
Like any other challenge on the lake, however, there is give and take on keeping the water moving, according to Flynn.
In past years, an aquatic dye was used to restrict photosynthesis and weed growth in the lake, Flynn said. The dye costs about $9,000 a treatment but quickly leaves a lake with moving water, usually within two to three weeks.
“So, we kind of have to make a choice: Do we want the dye and the effects we get there, or do we want the water quality improvement that we get from flowing the lake?” Flynn said.
The service agency manages more than just water depth, however, as lake weeds are mowed for about 6 months out of the year. Flynn said the service agency will ideally begin mowing in late March or early April and continue through October.
The lake mower works a consistent schedule across five zones each day of the week. Flynn said the mower hits the scheduled zone in the morning before addressing areas with excessive weed growth in the afternoon.
“You might see the boat mowing behind someone’s house more but that’s because there are more weeds there,” Flynn said. “We’re trying to be as efficient as we can.”
A copy of the service agency’s lake mowing schedule can be found on its website, stansburypark.org.
Once they are mowed and collected, the weeds are loaded into a trailer and transported to a pig farm in Erda, where they are used as feed. Flynn said about 3 tons of weeds are removed from the lake every other day throughout the course of the lake mowing season.
While the sago pondweed gets residents’ attention due to its prevalence, a pair of aquatic plant species that appear in the lake are a greater threat, Flynn said. Both tamarisk and phragmites can be found in the lake, and are considered noxious weeds by the state.
Tamarisk, also known as saltcedar, grows from 5 to 20 feet in height, and was originally introduced from Eurasia, according to the Utah Weed Control Association.
Phragmites is an invasive species that crowds out native species and inhibits water movement, according to the Utah Division of Wildlife Resources.
Flynn said there was no phragmites in Stansbury Lake until about 5 or 6 years ago, when a resident brought it in and planted it behind their home. He said the noxious weed is sometimes confused with cattails.
“(Phragmites) has now spread to where if we weren’t actively controlling it, it would literally take over this lake and turn it into a swamp,” Flynn said.
The service agency will assist residents in identifying noxious weeds on their property, but Flynn said property owners are required to remove them. He said the service agency can also help residents identify the proper chemicals and get them in touch with the county’s weed division.
Phragmites is the only foreign species introduced to the lake, however, as Flynn said he sees turtles, fish and other fauna that don’t belong.
“Every year I’ll be out on the golf course and see a new crop of goldfish swimming around, or somebody’s koi,” he said.
Flynn said frogs were also introduced by a resident, which now populate the lake. The frogs serve as food source for wildlife, including herons and bass, but Flynn said even a seemingly beneficial addition can alter the lake.
“It’s never a good idea to randomly introduce new species into a new ecosystem, because then the ecosystem has to adjust,” he said.
While weeds and introduced wildlife are concerns for the service agency, Flynn said he fields the most complaints from residents about a different species — humans. Specifically, the use of the lake by non-residents.
“I have people complaining about non-resident use of the lake more than I have people complaining about the condition of the lake,” Flynn said.
Stansbury Lake is a private lake and the service agency maintains a permit, renewed every five years, for that designation. Flynn said he’s observed use by non-residents and said he believes most people using the lake are from outside the community, including visitors from Salt Lake County.
But the service agency, a public entity funded by taxpayer money, has not been aggressive enforcing the private status of the lake, Flynn said.
“Our policy is that the lake is private and for the use of residents only,” he said. “There’s some question as to whether we can do that and enforce that, so we’re looking into that for this fall as well.”
The lake is funded entirely by the Stanbury Park Service Agency, but the lakeshore takes a beating from heavy use, Flynn said. The number of people using the lake increased following a shoreline restoration project completed in 2016, he said.
Residents are concerned with preserving the quality of the lake, according to Flynn.
“It’s not that residents want to be exclusive,” he said. “It’s they want to maintain the integrity of the lake and the beauty of it so it will last for generations and not just get trashed.”
The SPSA board will review the future of the lake in the fall and decide on a plan and priorities for its preservation, Flynn said.
SPSA board chairman Neil Smart said his priority is creating an equilibrium between resident use of the lake and ensuring a healthy ecosystem.
“I’d like to have a good balance there, where the lake is healthy but people can recreate,” Smart said.
SPSA board member Gary Jensen said weeds on the lake are a primary concern for residents, based upon the past 6 months of meetings. He said he recognized worry about non-resident use of the lake, but viewed the care of the lake as the critical concern.
For Flynn, he said he’s lucky to live in a community with a unique feature like Stansbury Lake and said many residents feel the same way.
“They realize what they have and they know it’s a precious thing,” he said.