Highland Park gets help on sewers

Highland Park gets help on sewers

July 23rd, 2012 by Cliff Hightower and Pam Sohn in News

Highland Park, one of Chattanooga's oldest neighborhoods, is set to undergo the development of new green infrastructure, including bioswales, rain gardens, more landscaping and the retrofit of sewer and stormwater control. The project is part of a $250 million consent decree Chattanooga has signed with the U.S. Environmental Protection Agency.

Photo by Allison Love /Times Free Press.

Highland Park's very history is built around water.

Developed in the late 1800s after the great floods, it was named for the high land provided to home-owners who were tired of being swamped by Tennessee River and Chattanooga Creek floods.

Now the area - still dotted with Victorian, American Foursquare and bungalow homes - is going to lead the way again.

This time, thanks to a forgiving federal penalty, it will be a demonstration project for how to retrofit failed and poorly designed wastewater and drainage systems in a neighborhood that has seen better days but is still awash with opportunity.

"This is not just green infrastructure; it's neighborhood revitalization," said John Bridger, executive director of the Chattanooga-Hamilton County Regional Planning Agency, during a brainstorming meeting on the project Friday.

Last week, the U.S. Environmental Protection Agency and the U.S. Department of Justice announced that Chattanooga has agreed to spend $250 million fixing its sewage treatment and stormwater system that since 2005 has dumped more than 354 million gallons of raw sewage into the Tennessee River.

The city also was fined $476,400, but EPA is allowing half that amount to be spent retrofitting Highland Park streets with green infrastructure -- today's buzzword for water-smart drainage that replaces the concrete ditches and sewer grates that line most city roads.

Curt Zacharias, a resident of Highland Park, stood Friday morning outside his home on Holly Street, an area that should see a complete overhaul within five years. He bought his house three weeks ago but has lived in Highland Park for three years and loves the neighborhood.

He wants to see traffic slowed down. He said a roundabout on Holly Street with plants that provide better stormwater filtering may be a good idea.

Because federal regulators came down on Chattanooga with a penalty that includes a stipulation for a green project, he now has an opportunity to see improvements on his street.

"We lucked out then," Zacharias said.

City engineers at the brainstorming meeting said they see a chance to get buy-in from builders for the soon-to-be adopted toughened stormwater programs requiring all new development to retain on site the first inch of any rain that falls.

"We're going to be telling everyone they have to do this. We have to understand what it takes and how to do it ourselves," said Bill Payne, city engineer.

The fix will make the streets prettier and improve property values, but the hidden benefit is alleviating stormwater runoff and the pollution it causes when it chokes the city's combined stormwater and sewer lines and makes the Moccasin Bend Sewage Treatment Plant overflow to the Tennessee River.

How it fits

What does one of downtown's most elevated neighborhoods have to do with sewage flooding the river?

Age and gravity.

Highland Park is dry because the water from it flows downhill, and all that water makes the headwaters of Dobbs Branch, one of the main feeder streams of Chattanooga Creek. That flows to the Tennessee River -- but not before some of it gets whooshed into some of the city's oldest piping.

When the oil-sheened and sewage-tainted water fills any one of Chattanooga's several stormwater storage tanks faster than it can be pumped to Moccasin Bend plant, it overflows to the streets and the river.

In Highland Park, the headwater stream of Dobbs Branch once flowed with the contours of the land. Now it begins under old warehouses and flows under a soccer field and street to come out of a culvert and into a concrete ditch.

One idea offered at the city's brainstorming session last week was that the creek beneath the warehouses might be restored and serve as both a community park and a natural basin to catch and naturally treat stormwater if Tennessee Temple is willing to partner with the city.

The warehouses and soccer field are owned by Tennessee Temple University, the largest landowner in Highland Park. Temple's new president, Steve Echols, called the idea "encouraging."

"We desperately need some stormwater relief. I think we pay about $80,000 a year in stormwater fees because we have so much concrete," he said. "It will all depend on some of the details."

Help for a stream

Dobb's Branch needs relief, too, Payne said.

The city engineer stood over a storm drain Friday, looking into it. Rocks, leaves and even a brick lay at the bottom of the drain. Across the street, a paper cup sat sideways on the edge of the road and a pile of cigarette butts rested a couple of feet away.

The cup and the butts have no other place to go if they aren't cleaned up, he said, and will wash to the storm drain just 10 feet away. The rocks, the leaves, the brick, cup and butts all have one destination if not cleaned up: Dobb's Branch.

"Ultimately, they will wind up in it," he said.

That's why stormwater is such a major cause of water pollution.

So any real fix has two elements.

The first is to replace or repair sewer lines to isolate sewage from stormwater as much as possible. To accomplish that, part of the city's mandated $250 million fix calls for the repair of 40,000 linear feet of 8-, 10- and 12-inch sewer lines using lining within the pipes. But that comes strictly from sewer funds.

From both a monetary and engineering standpoint, the city's overall sewer rehabbing has nothing to do with the demonstration project, which is the second fix.

Its goal is to lessen stormwater's gush to the street drains, which hopefully will be accomplished with street gardens, tree boxes and pervious pavement -- paving that allows water to soak through it instead of flow across it. That work must be paid for with $238,200 -- half of what Chattanooga would have had to hand over in cash as a penalty to EPA. The consent decree -- the technical name for the agreement between the city and the EPA -- specifies that no part of the expenditure may be paid for with federal or state funds, including low-interest loans, contracts or grants.

City officials are, however, hoping they may enhance the project with help from community partners such as foundations, businesses or residents.

Generally, green infrastructure costs about $100,000 to $200,000 an acre, officials said, and they want to cover more ground than that.

According to the consent decree, Chattanooga has six months to develop a plan identifying the proposed location of the green infrastructure elements. Once the state and EPA approve the plan, city workers have 48 months to complete it.

And six months after its completion, they must conduct a technical workshop to train local engineers and landscape architects on green infrastructure site design.