Putting curves back in streams

Putting curves back in streams

June 11th, 2010 in Green

When rain deluged the Hickory Creek townhouse subdivision in March, sewage started bubbling up from the manhole in front of Dixie Parnell's house.

"The smell was terrible and we couldn't even get the mail from our mailboxes for a couple days," she recalled. "It was a real mess and, unfortunately, this wasn't the only time this has happened."

Behind Ms. Parnell's home now lies what may be part of the solution for such overflows and a new way to improve the region's water quality. Starting next month, a concrete viaduct built between Hickory Creek townhomes and an adjacent golf course will be dug up, reshaped and restored to a more natural stream.

The $1.2 million project is the first in Hamilton County but the 22nd for a state agency created more than seven years ago to help restore impaired streams by putting them back to a more natural state.

Using fees assessed against private developers and the Tennessee Department of Transportation for projects that alter natural streams, the Tennessee Stream Mitigation Program has already restored more than 33 miles of Tennessee streams to a cleaner and more natural state.

"We hope to see a significant difference from this project," said Eric Chance, operations manager for the state program. Hickory Creek "is one of the impaired streams in the state and we hope this project can help improve the water and wildlife in the area.

The Tennessee Stream Mitigation Program targets impaired streams where vegetation and aquatic life have been reduced and stream restoration will help improve water quality, Mr. Chance said. The agency claims its projects have resolved about 82 percent of the problems in its streams.

With a more winding path, additional vegetation and a slower stream flow, the reshaped stream behind Hickory Creek townhomes also could help limit runoff during heavy rains compared with the drainage-style ditch built by the original developer of Hickory Creek townhomes.

The city is giving up part of the golf course it bought for the project. But backers see the changes in the stream and the golf course like a hole in one for residents and the city.

The city leases the unnamed 9-hole golf course to the University of Tennessee at Chattanooga for the school's golf program and to Chattanooga's First Tee program, which teaches youngsters how to golf. A more natural stream will be a better buffer between the golf course and the Hickory Creek development, according to golf and city officials involved with the project.


SUNDAY -- Overview

MONDAY -- Utilities

TUESDAY -- Where do flushes go?

WEDNESDAY -- Health impact

THURSDAY -- Development and runoff

TODAY -- Stream restoration

SATURDAY -- Lessons from other cities

SUNDAY -- What's next: Tomorrow's green technology

Tennessee stream mitigation program

* 22 -- Number of restoration projects, including the Friar's branch project set to begin in July in Chattanooga

* 33.7 -- Number of miles of Tennessee streams restored since the program began in 2003

* 400 -- Number of acres of aquatic and riparian habitat restored

* 82 -- Percent of negative impacts on streams mitigated by the restoration projects

Source: Tennessee Stream Mitigation Program, www.tsmp.us

Chattanooga City Engineer Bill Payne said the stream restoration should help improve the city improve water quality in the Friar's Creek watershed and may aid in holding back runoff during heavy rains.

"It doesn't solve the flooding problem, but it should help," Mr. Payne said.

During a meeting with Hickory Creek residents this spring, city officials acknowledged that when rains become too great, stormwater lines can be overwhelmed and streets can flood.

"One thing I discovered in my 40 years as an engineer is that I cannot out-design God," said Jerry Stewart, director of Chattanooga's waste resources division. "At the present time, we have 1,250 miles of sewers and 29,000 manholes and when it rains we have issues all over the city."

City Councilman Jack Benson said fixing all of the city's stormwater sewer problems will be expensive.

"To do all the things to fix all of the problems that you want to have done is going to require an increase in your sewer fees paid on your monthly water bills," Mr. Benson told Hickory Creek townhouse owners in April. "We have as many miles of sewers as we do streets in Chattanooga and that costs a lot to maintain."

But reducing the amount of paved lots and concrete ditches like those in and around Hickory Creek Townhomes could provide a solution to part of the runoff problem, Mr. Chance said.

Residents in Hickory Creek are generally eager for the latest stream restoration project to begin, according to Judie Merritt, manager of the Hickory Creek Townhouse Association.

"People are really getting upset now because people here were told last year something was going to happen," Ms. Merritt said. "This has been going on for a year and we all thought something would have been done long before this."

Mr. Chance said the project was delayed while the state secured permits for the work from other state and federal agencies. He said crews are expected to begin work on July 6.