FAYETTEVILLE — The company that treats city sewage is looking for a way to clean up Lake Sequoyah.
Workers with CH2M Hill and Muskogee, Okla.-based Sludge Technology started dredging a portion of the 400-acre lake in southeast Fayetteville last week.
They hope to improve water quality by removing tons of sediment that has built up in the lake for more than 50 years.
David Jurgens, city utilities director, said tests show Lake Sequoyah holds a staggering amount of sediment and nutrients, such as nitrogen and phosphorus. It would take the city’s Noland Wastewater Treatment Plant more than 500 years to generate the amount of phosphorus that rests at the bottom of the lake, Jurgens said. The sewage plant, like Lake Sequoyah, discharges into the West Fork of the White River.
By the Numbers
Lake Sequoyah
5 billion: Approximate pounds of sediment in Lake Sequoyah
3.625 million: Approximate pounds of phosphorus in that sediment
93.4: Pounds of phosphorus per day the Noland Wastewater Treatment Plant is permitted to discharge into the West Fork of the White River
Source: City Of Fayetteville
Phosphorus is of particular concern in Northwest Arkansas. It can produce blue-green algae, which, in high volumes, chokes out aquatic life and, in drinking water sources, causes taste and odor issues.
Lake Sequoyah, which was formed by damming the east and middle forks of the White River in the 1950s, eventually flows into Beaver Lake, the drinking water source for thousands of Northwest Arkansas residents.
Billy Ammons, regional manager for CH2M Hill, said the city isn’t yet facing stricter standards for phosphorus discharge at the Noland plant like it is at the West Side Wastewater Treatment Plant on Broyles Avenue. The west side plant discharges into the Illinois River.
“The chances are good we’ll see potential regulatory pressure (at Noland),” Ammons said. “If we can do things in a proactive way, then we may be able to avoid that requirement.”
He and Jurgens said a cleaner Lake Sequoyah also benefits fishermen.
Mike McBride, who runs the Lake Sequoyah bait shop, said there are areas fishermen can’t get to because of sediment buildup.
“In some places where it used to be 8 or 9 feet (deep), now it’s 1 foot,” McBride said.
“I’d be in favor for getting it dredged out,” he added. “That’d be the best thing that could happen out here.”
Crew members with Sludge Technology drove a hydraulic pump into the bottom of the lake from a floating platform Wednesday. A blade chopped up mud and sucked it into a tube that ran to shore. Murky brown liquid flowed into two large containment ponds, where sediment was filtered out. After drying in the sun, the sediment will be tested to see if it is safe to be sold commercially or used as topsoil for city projects.
The sediment doesn’t just contain nutrients from eroded stream banks and stormwater runoff. It carries traces of pretty much anything that washed into Lake Sequoyah from upstream, Jurgens said.
Ammons said preliminary tests have not shown elevated levels of heavy metals or other potentially harmful contaminants.
Jurgens said the goal of the program is not to make money, but, he added, the city could save money on dredging if sediment is reused as topsoil. He said if the roughly $60,000 pilot program is determined to be effective, Lake Sequoyah could be dredged often as part of CH2M Hill’s annual contract with the city.