Page 10 - March-April 2015 Vol.32 No.7
P. 10
city of chattanooga By Justin Holland
Green Infrastructure Retrofit
Demonstration Project
Project Scope/Objectives Fig. 1: Vicinity Map cent of the Total Suspended Solids from
runoff generated by a design storm up to
At the direction of the State of Tennessee, South Hawthorne Street, and a one block and including 2.1-inches of rainfall over
the City of Chattanooga is to retrofit, using section of South Holly Street between a 72-hour period. The vast majority of all
Green Infrastructure practices, a portion of Anderson Avenue and Vance Avenue (see of the polluted urban runoff is dislodged
the historic Highland Park neighborhood. Figure 3 – Project Site). from disturbed areas and hard surfaces
The purpose is to collect, treat and improve and is conveyed by this event.
stormwater runoff in the project area, Project Description/Green
which will improve water quality in Dobbs Infrastructure Practices City design professionals initially con-
Branch (an impaired stream which flows sidered all Green Infrastructure practices
into Chattanooga Creek). To meet objectives, the demonstration and then focused on those deemed most
project will use varying Green Infrastruc- effective after weighing the given existing
The use of Green Infrastructure prac- ture practices within the rights-of-way of beneficial systems alongside site limita-
tices in the project area will replace and/ portions of Anderson Avenue and South tions and restrictions. A few of the consid-
or work in conjunction with the existing Holly Street. It will also serve as a model erations were the limited space within the
conventional, engineered stormwater demonstration project for future construc- right-of-way, existing street trees, and resi-
collection system, and help mitigate the tion projects within the city, and be used as dents’ on-street parking. After thorough
effects of urbanization on the water qual- a research site to gather performance data research and consideration, staff proposed
ity. Using Green Infrastructure, the project on various Green Infrastructure practices. that the Best Management Practices for
will reduce the quantity and improve the It is unique in this area as it addresses this particular site include the following
quality of the runoff, as well as reduce stormwater runoff at its source with the from the City of Chattanooga Rainwater
Total Suspended Solids for this sub- integration of private property improve- Management Guide:
watershed. This result is achieved when ments alongside public right-of-way 5.3.1 Pervious Pavement
the installed systems manage and treat the improvements. Integration will be achieved 5.3.2 Subsurface Infiltration Beds
small, frequent storms that account for a by working with and partnering with the 5.3.9 Runoff Capture and Reuse
large portion of the pollution. homeowners throughout the project. 5.3.11 Flow-through Planter Boxes
5.3.12 Manufactured Devices
In addition to improving the water qual- South Holly Street Retrofit
ity, other benefits are anticipated through The existing layout of South Holly
the implementation of this project. It is The right-of-way for South Holly Street Street will remain mostly unchanged.
to be a pilot/demonstration project in between Vance Avenue and Anderson Currently no delineated parking spaces
the City for Green Infrastructure design Avenue is 50-feet wide. Existing improve- exist; therefore, residents park along the
standards and construction, to be used ments consist of approximately 30 feet of street. To accommodate Green Infrastruc-
by public and private sectors in future asphalt pavement roadway, 6-inch curbs ture practices, the roadway width will be
projects, encouraging developers to include and approximately 4-feet sidewalks. The lessened to accommodate delineated on-
water quality protection in their projects. Green Infrastructure proposed for this
Another benefit is the opportunity to work portion is anticipated to remove 80 per-
with the public and stakeholders in the
project area, to allow neighborhood owner-
ship and promote the long-term success of
this environmental project.
Project Location
The project is located east of down-
town Chattanooga in an area known as
Highland Park (see Figure 1 – Vicinity
Map), within the subwatershed of Dobbs
Branch, which is an impaired stream listed
on the Clean Water Act 303(d) list (see
Figure 2 – Subwatershed Area).
This project retrofit will encompass that
portion of the subwatershed along two
blocks of the Anderson Avenue right-
of-way between South Holly Street and
10 TPW March/April 2015
Green Infrastructure Retrofit
Demonstration Project
Project Scope/Objectives Fig. 1: Vicinity Map cent of the Total Suspended Solids from
runoff generated by a design storm up to
At the direction of the State of Tennessee, South Hawthorne Street, and a one block and including 2.1-inches of rainfall over
the City of Chattanooga is to retrofit, using section of South Holly Street between a 72-hour period. The vast majority of all
Green Infrastructure practices, a portion of Anderson Avenue and Vance Avenue (see of the polluted urban runoff is dislodged
the historic Highland Park neighborhood. Figure 3 – Project Site). from disturbed areas and hard surfaces
The purpose is to collect, treat and improve and is conveyed by this event.
stormwater runoff in the project area, Project Description/Green
which will improve water quality in Dobbs Infrastructure Practices City design professionals initially con-
Branch (an impaired stream which flows sidered all Green Infrastructure practices
into Chattanooga Creek). To meet objectives, the demonstration and then focused on those deemed most
project will use varying Green Infrastruc- effective after weighing the given existing
The use of Green Infrastructure prac- ture practices within the rights-of-way of beneficial systems alongside site limita-
tices in the project area will replace and/ portions of Anderson Avenue and South tions and restrictions. A few of the consid-
or work in conjunction with the existing Holly Street. It will also serve as a model erations were the limited space within the
conventional, engineered stormwater demonstration project for future construc- right-of-way, existing street trees, and resi-
collection system, and help mitigate the tion projects within the city, and be used as dents’ on-street parking. After thorough
effects of urbanization on the water qual- a research site to gather performance data research and consideration, staff proposed
ity. Using Green Infrastructure, the project on various Green Infrastructure practices. that the Best Management Practices for
will reduce the quantity and improve the It is unique in this area as it addresses this particular site include the following
quality of the runoff, as well as reduce stormwater runoff at its source with the from the City of Chattanooga Rainwater
Total Suspended Solids for this sub- integration of private property improve- Management Guide:
watershed. This result is achieved when ments alongside public right-of-way 5.3.1 Pervious Pavement
the installed systems manage and treat the improvements. Integration will be achieved 5.3.2 Subsurface Infiltration Beds
small, frequent storms that account for a by working with and partnering with the 5.3.9 Runoff Capture and Reuse
large portion of the pollution. homeowners throughout the project. 5.3.11 Flow-through Planter Boxes
5.3.12 Manufactured Devices
In addition to improving the water qual- South Holly Street Retrofit
ity, other benefits are anticipated through The existing layout of South Holly
the implementation of this project. It is The right-of-way for South Holly Street Street will remain mostly unchanged.
to be a pilot/demonstration project in between Vance Avenue and Anderson Currently no delineated parking spaces
the City for Green Infrastructure design Avenue is 50-feet wide. Existing improve- exist; therefore, residents park along the
standards and construction, to be used ments consist of approximately 30 feet of street. To accommodate Green Infrastruc-
by public and private sectors in future asphalt pavement roadway, 6-inch curbs ture practices, the roadway width will be
projects, encouraging developers to include and approximately 4-feet sidewalks. The lessened to accommodate delineated on-
water quality protection in their projects. Green Infrastructure proposed for this
Another benefit is the opportunity to work portion is anticipated to remove 80 per-
with the public and stakeholders in the
project area, to allow neighborhood owner-
ship and promote the long-term success of
this environmental project.
Project Location
The project is located east of down-
town Chattanooga in an area known as
Highland Park (see Figure 1 – Vicinity
Map), within the subwatershed of Dobbs
Branch, which is an impaired stream listed
on the Clean Water Act 303(d) list (see
Figure 2 – Subwatershed Area).
This project retrofit will encompass that
portion of the subwatershed along two
blocks of the Anderson Avenue right-
of-way between South Holly Street and
10 TPW March/April 2015
