The City of Knoxville’s efforts to restore Fountain City Lake took a major step forward Tuesday night, when City Council voted unanimously to authorize a contract of up to $91,250 with a Knoxville company to install a new pump, pipes and other infrastructure essential to maintaining this community resource.
The pump, to be installed by Design & Construction Services Inc. by late spring, will restore constant circulation in the lake, increase oxygen levels in the water and moderate temperatures – all of which will reduce the growth of algae.
“This iconic lake is truly cherished, and we’re taking careful, thorough steps to restore it in such a way that our children and grandchildren will be able to enjoy its beauty many decades from now,” Mayor Madeline Rogero said.
“We always understood that rehabilitating Fountain City Lake would be a long-term project. We’re not finished yet, but I’m pleased that we’re well on our way toward returning the lake to its former grandeur.”
Last fall, work began with a repair of a leak in the earthen berm that surrounds the 125-year-old manmade but spring-fed lake. A new water outlet structure was installed last year. Those initial improvements allowed the lake to fill to its proper depth.
Because algae thrives in warm, stagnant, shallow water, both deepening the lake and aerating the water with the new pump and plumbing are critical upgrades.
Additional steps, like creating a small wetland area in what’s now a shallow spot on the lake’s northern end, are planned for later this spring and early summer.
This next step would aid habitat diversity while reducing the size of a stagnant zone of water that’s been conducive to the growth of thick algae. The wetland vegetation also would filter pollutants and absorb some of the nutrients from waterfowl feces that are now in the water and promoting algae growth.
The wetland area will be planted with native species, and the lake will be restocked with triploid grass carp and blue tilapia to control aquatic vegetation. Chemical algaecide will be sparingly applied if needed.
Last August, Mayor Rogero, City Council members, City engineers, experts with environmental engineering firm LDA Engineering, Fountain City residents and lake stakeholders shared ideas at a public meeting, held at the Lions Club Building at Fountain City Park, 5345 N. Broadway.
LDA Engineering identified three major culprits causing the excessive algae:
• Waste from too many waterfowl, compounded by public feedings;
• Shallow, stagnant, warm water;
• An imbalanced ecosystem.
David Hagerman, a City stormwater engineer who’s been working on the Fountain City Lake project, said the pump, wetland creation and restocking of the lake with sustainable species of plants and fish will restore the lake’s health – so long as lake visitors do their part as well.
“Almost all of the bacteria and nutrients that feed the algae originate with the waterfowl,” Hagerman said. “Feeding bread to ducks is harmful to their health because it changes their migration instincts, and it promotes an artificially high overpopulation of waterfowl at the lake.
“The high population and overfeeding produces way more waste than the small lake and park can handle. The result is unsightly and unhealthy for humans and wildlife.
“While the physical infrastructure upgrades are needed, the most critical improvement for a long-term clean and healthy Fountain City Lake is actually changing our behavior. Please don't feed bread, dog food or grain to the ducks. Please leave the food and trash at home – and enjoy the park and its wonders. We believe families will enjoy the wetland feature as a fun new educational amenity.”