Blog: City Blog

City Engineers Go From Problem to Solution

Every ardent “Apollo 13” movie fan remembers the scene. When engineers save the day.

Within a very finite timeframe, they built the very thing that would keep the astronauts alive and ultimately safely bring them home to earth.

The engineers went from problem to solution. They always do.

Here in Knoxville last week, the day of a massive fire at a privately owned recycling plant in North Knoxville, City Engineers were already preparing to monitor the waters of Second Creek for ash and other pollutants. They would also look for dead fish – always an obvious way to recognize troubled waters.

The garbage fire spanned two acres. Burning piles of cardboard, plastic and other trash sent smoke into the sky, ultimately prompting evacuation of about 100 homes in 13 city blocks. City firefighters worked tirelessly as they dumped millions of gallons of water on the blaze to control it.

“There were no dead fish in Second Creek, but there were a few oxygen-low areas in the waters, and we saw very few fish swimming,” said Chris Howley, City Engineering Planning Chief, who oversees the Stormwater Division.

On May 1, the day of the fire, booms were placed to help prevent pollutants from reaching the six-mile creek. The Tennessee Department of Environment and Conservation and City Engineers also did a walk-through of the creek the next day and determined no serious concerns with water quality.

But Howley and colleague David Hagerman took extra precautions.

“We wanted to find a way to quickly churn the creek waters by pushing in air. Improving those areas of low oxygen levels would improve aquatic life health,” said Hagerman, City Stormwater Engineer Manager.

By Friday, May 3, engineers had designed and placed two pumps and two air compressors that pushed air bubbles into several oxygen-hungry areas of the creek. Their quick work produced significant, positive results.

This week’s two inspections by City engineers at six different Second Creek locations found in just a few days hundreds of fish - multiple species - as well as frogs and turtles. These earlier low-oxygen creek waters were now well above levels deemed acceptable, as well as rich in aquatic life.

“The improvement was clear and substantial. We’re always working to meet Knoxville’s goals for rivers and creeks to be fishable and swimmable,” said Hagerman.

City Engineers know these kinds of serious fires in Knoxville are infrequent, and they also know last week’s oxygen-improving aquatic tools were a temporary fix.

They want better tools for the future. And so stormwater engineers are designing a more nimble water quality plan that will call for four permanent aquatic kits and training on their use.

“Our goals call for this, and it makes sense to have a permanent solution in place,” Howley said.

Despite how infrequent such emergency events occur annually, the City is in the response business. The new engineering plan calls for low, medium and high level generators that improve the water quality when a fire or other event occurs that can impact aquatic health.

“We never know when a large fire will happen, so we endeavor to be ready when it does. These aquatic kits are another tool in the shed for us,” Howley said.

Posted by On 14 May, 2019 at 8:27 AM