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Wednesday, February 24, 2010

"The Land of 10,000 Lakes": A Neighborhood's Growing Problem

Lately, Riverview has reminded a lot of people of Minnesota. Lately, every time it rains, the community becomes that state's nickname: "The Land of 10,000 Lakes."

Of course, that's an exaggeration. But when water is standing in your backyard that hasn't stood there in years, you gotta wonder what's going on.



The heavy snows and rains of the winter, have apparently soaked the ground in Riverview so badly, backyard puddles have turned into ponds that rival the water traps you see at Meadowview's golf course.

The city of Kingsport says, the ponding is nothing unusual, given the amount of rain and snowfall the past few weeks.



"These pictures can probably come from just about any resident in Kingsport," says city Public Works Director Ryan McReynolds. "Anybody that has flat spots in their yard has experienced standing water recently, especially if they're in a low-lying area."

"And Riverview is definitely in a low-lying area."



Through the years, it's no secret that part of Kingsport's African-American community is located in an area near the South Fork Holston River, that has several aquifers (underground water streams in caves and caverns) that feed the river. Due to the fact that the groundwater table could have been affected by the chemical and industrial waste dumpsite the community was built on many years ago, whenever there is standing water in yards, it raises the concerns of local residents, many of those who have contacted the Douglass website and city administrators with concerns.

But Mr. McReynolds says, he has noted only one concern that has gotten his interest.



"We have noticed a lot of flooding in the streets, in relation to the construction on the HOPE VI homes and the V.O. Dobbins Center," he says. "The only thing we could determine with some of the street flooding, was that there was a problem with one of the techniques that the contractor is using for erosion control. Some of the netting had started channeling water in places near storm drains..it was holding back sediment and water, and the sediment was not letting the water get through to the drains. At one point, we had to have him cut the netting, to allow water to drain through, yet keep trapping the sediment. It's a difficult balance, but it's necessary."



As for the ponding in nearby backyards, McReynolds says, he is sympathetic with local property owners, but right now, water is standing because it doesn't have any other place to go.

"Even if the water seeps into the underground water table," he says, "it still is finding water already there, and it will dam up towards the surface. As the system relieves itself of the pressure, the water will, of course, go down. It may take several weeks for the underground aquifers to shed themselves of the excess water, in order to allow the surface water to come on down."



The tremendous pressure that is underground, can be seen in stormwater manholes, like this one on Industry Drive near Wheatley Street. Water that normally runs into the recepticle was so backed up the day we noticed it, that the backed-up pressure was forcing water to bubble up through the manhole cover, and spill down in a cascading waterfall into the ditch along Industry Drive. From there, it was just a short journey underneath Eastman's railroad tracks and into a churning Holston River, South Fork.

McReynolds says, that's typical of an overloaded stormwater system.



"Water will always seek the lowest point of travel downhill," he says. "Whenever pipes, aquifers, street drainage systems, and backyards are backed up, the pressure increases on the lowest end of travel, and in all case, it's always at manholes along the escape route. We have the manholes locked down so that the pressure stays inside the concrete and steel structure, but unfortunately it does create backups back up the chain. Give it a few hours, and the pressure will always relieve itself."



"At the beginning of that process, is backyards and street drains," McReynolds says. "When the water table gets too high, that water has no place to go until the downward pressure is relieved. Until then, water will sit in the backyard or on the street corner. It's not necessarily a bad thing, but too much rainfall or snowfall just aggravates an already aggravated system."

But the city Public Works office will continue to monitor the drainage system in Riverview. McReynolds says, other situations may be taxing the stormwater runoff in ways that cannot be detected or explained.



"I will definitely continue to look into the stormwater conveyance system through the community," he says, "just to make sure that there isn't something abnormal that can't be explained. But I would not be as worried about water in backyards, as I would about water in the streets."

"That could signal a much bigger problem."

For any water runoff problems, Riverview residents can call Ronnie Hammond at Kingsport Public Works at 229-9451. For problems relating to the HOPE VI Homes or V.O. Dobbins Complex construction projects, call the Kingsport City Manager's Office at 229-9412.