Fluoride Action Network

The long and winding water treatment process.

The Robesonian | December 16, 2022 | By Copeland Jacobs
Posted on December 16th, 2022

LUMBERTON — The City of Lumberton’s Water Plant resembles in ways a medieval castle, with earthen walls and moats ringing an imposing, purposeful collection of structures.

“People think water runs in one pipe,” said Chief Operator Paul Valenti, “and runs out the other.”

Water treatment is far more involved than a simple input-output. Valenti is among the people charged with ensuring the residents of Lumberton can drink, bathe, and brush their teeth with peace of mind. This job he and the staff at the water treatment facility do well, as the reports of the water contaminants listed on the drinking water quality report is enormously shorter than the list of all possible water contaminants which is pinned to the laboratory wall.

“If it’s not in the water,” Valenti said about the comparatively smaller drinking water quality report, “Why should I put it in the report if it’s not in the water?”

The goal according to him is to make the water as clean as possible within the parameters using the available equipment. The process is complex and chemicals like fluoride and chlorine are involved.

“They used it in World War One for chemical warfare,” Valenti said about chlorine.

A desk in his office holds five binders dedicated to chlorine safety. There are two immense volumes in his office to be studied for certification. Valenti said you couldn’t just get people off the streets. The plant takes safety seriously and Valenti said people are on call all the time at the facility.

Fluoride, which Valenti said is added to the water to strengthen children’s teeth, is also poisonous in large quantities. It too must be carefully managed. However, there is no single main problem with water treatment.

“It’s like going to the beaching and saying which grain of sand is going to be your problem that day,” Valenti said.

The City of Lumberton’s plant is designed to deal with natural contaminants, such as catfish, which are kept from the water supply by screens that also remove leaves, sticks, and other large items that probably wouldn’t fit into a glass of water, according to a document provided by Valenti.

After the well and river water is screened for large undrinkable things coagulants are added to the water in the flash mix. These cause smaller particles in the water to cling together and form large particles which are easier to remove from the water. Coagulation also helps remove color and turbidity, a term for soil particles in the water. (check this)

And then there is flocculation. According to the first of the two-volume set Valenti said needed to be studied for relevant certification, flocculation is putting many smaller particles into larger particles which are easier to remove from the water. This is likely more difficult in wintertime, as cold water doesn’t want to settle.

Following flocculation the larger particles settle out, which is called sedimentation, according to the chart on the document, and the remaining suspended particles are removed with filters. The next stage is postchlorination to kill disease-causing organisms.

After this process chemicals are added to keep corrosion under control. Valenti said the Flint water contamination was caused by the absence of corrosion inhibitors to prevent metal from seeping into the water.

“When you get things in there that are man-made,” Valenti said, “it’s a whole new ballgame.”

The water plant has a laboratory for conducting tests on the water to ensure safety. If contamination is detected the tests are run more often. Tests are sent to a state-certified independent lab.

“If there’s a violation,” Valenti said, “the state gets it immediately.”

The laboratory contains such spectacularly named devices as the PB-700 Jartester and the 2100AN Turbidimeter, highly sophisticated testing equipment bearing no small resemblance

“They’ve been using these since the beginning of time,” Valenti said.

According to Valenti some tests cannot be conducted as often because of their prohibitive costs. Tests can cost as much as $1-2,000.

He said the technology for testing has improved and they are now looking for things which might’ve been in the water before but were previously undetectable through testing.

“The state is always lowering the MCL,” Valenti said about the maximum contamination level in the water.

The total organic carbon removal is expected by the state to be 45 while the facility has achieved 70.

Near the end of the process the water is sent into a large structure containing a maze which gives the water additional time to be made safe to drink.

According to a piece of “gee whiz” information from Valenti the City of Lumberton has been treating water since 1910, initially without the significant use of chemicals. A second treatment plant constructed in 1952

Waste sludge from the treatment process is kept in a lake behind the facility. This sludge is then used for land application. Valenti said there was nutritional value from the the fecal waste which is why it is added to nonproductive soil. The sludge is batch-tested at the waste treatment plant beforehand. He said crops grown using the sludge were not to be eaten, but animals fed using these crops were safe for human consumption.

“You don’t eat the corn,” Valenti said, “but you can eat the hog.”

*Original full-text article online at: https://www.robesonian.com/news/240941/the-long-and-winding-water-treatment-process