Facts on Integrated Water Plan and Harpeth River

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**NEW see Aquatic Resource Alteration Permit presentation to TDEC at Public Hearing on October 21, 2014

See Response to Harpeth River Watershed Intent to File lawsuit from March 2014.  See the video presentation made to the Board of Mayor and Aldermen youtu.be/eOorOGLyp_A

The Water Management Department has outlined some common questions that are asked in relation to the permitting and operation of the water and wastewater facilities, along with planning questions as the City’s continues to grow and expand its infrastructure needs.  Below are some common definitions that we use in our daily discussions that will help you to understand the regulatory process the water and wastewater operations experience.

Definitions 

  • Effluent – highly treated wastewater that is discharged into a water body
  • EPA (Environmental Protection Agency) – a Federal agency created to protect human health and the environment. When Congress writes an environmental law, the EPA implements the law by writing regulations, often setting national standards that the State of Tennessee enforces. With assistance from the Tennessee Department of Environment and Conservation (TDEC), the EPA calculates the Total Maximum Daily Loads (TMDLs) for impaired streams that regulate the quality of point source discharges, including wastewater treatment plant effluent.
  • IWRP (Integrated Water Resources Plan) – a document that incorporated potable water, wastewater, reclaimed water and stormwater use considerations within the City into a long-term plan that identifies infrastructure improvements and management tools to meet the City’s needs and customer requirements. This plan engaged stakeholders from the inception of the project to define the objectives, identify potential solutions, collaborate on the formulation of the analysis tool, and provide recommendations for the Board of Mayor and Alderman.
  • MGD (million gallons per day) – The units of measurement used to characterize the size of the City’s facility.  The City’s WRF has a current capacity of 12 MGD and the WTP has a current capacity of 2.1 MGD.  In comparison, the City of Los Angeles’ Hyperion Water Reclamation Facility is over 400 MGD, Nashville’s has three facilities with a combined capacity of 186 MGD.
  • WTP (water treatment plant) – The City owns and operates a WTP inside the City along the Harpeth River.  The WTP collects flow from the Harpeth River and stores in the 114 MG reservoir when not needed immediately, or treats the flow and pumps the drinking water into the distribution system that ultimately ends up at your faucet.
  • NPDES (National Pollutant Discharge Elimination System) – a program authorized by the Clean Water Act to control water pollution by regulating point sources that discharge pollutants into waters of the United States. The NPDES permit program in the State of Tennessee is administered by TDEC, the state regulating agency.
  • Point Source – a piped outfall that discharges into a waterbody. The City’s Water Reclamation Facility (WRF) is a point source discharge into the Harpeth River.
  • TDEC (Tennessee Department of Environment & Conservation) – the State regulating agency that implements actions set forth by the EPA.TDEC issues National Pollutant Discharge Elimination System (NPDES) permits to regulate point sources discharges and protect human health and the environment.
  • WRF (Water Reclamation Facility) – The City owns and operates a WRF inside the City along the Harpeth River. The WRF collects flow from areas within and outside of the City and treats the flow using natural processes to produce a high quality effluent. The City’s WRF is heavily regulated by TDEC and the EPA.

Water Planning

  1. I’ve been told the Harpeth River is the most unrecognized resource the City of Franklin has to offer its residents.Why is that?
    While we’ve heard that too, it is absolutely not true. The Harpeth River is forever present in the way the City conducts its business. This is reflected in the City’s stormwater management ordinance requirements, the Integrated Water Resources Planning efforts and implementation, restoration projects and water quality monitoring. The value of the river is also reflected in sustainability initiatives such as the Sustainability Commission and Sustainability Task Force, extending sanitary sewer to nearly 600 residential properties enabling them to decommission septic tanks, the use of the City’s reclaimed water system, just to name a few.

  2. Why doesn’t the City develop a comprehensive Harpeth River resource plan and not just a water supply plan?
    The City did just that, spending the last several years completing a very comprehensive Integrated Water Resources Plan with extensive input by a wide variety of community stakeholders. You can find the plan and other documents on our website at www.franklintn.gov/iwrp.

Water Safety

  1. Does the City have a water quality monitoring program for the water that is discharged into the river?

    Lab worker

    Yes. The City has a stringent water quality program to make sure its discharge is meeting the requirements of the NPDES permit issued by TDEC and the TMDL issued by the EPA. Each day the Water Reclamation Facility (WRF) is discharging effluent, the City samples the effluent for various constituents to make sure the discharge is in compliance with the limits set forth in the NPDES permit. The NPDES permit places stricter discharge limits on constituents during the summer months while the Harpeth River is at low flow stages. Table 1 below outlines the average loading the WRF discharges into the Harpeth during the summer months and Table 2 outlines the discharge loadings during the winter months. You can see the City discharges much less than what is allowed by TDEC in the City’s NPDES permit. The effluent the City discharges is safe, and its quality is often higher than that of the water that is already in the river.

Table 1 - Summer Discharge1

Effluent Parameters

Units

Monthly Average2

Permit Limit3

Discharge Percentage of NPDES Permit

CBOD5

lbs/day

59

400

15%

     CBOD5 Percent Removal

%

99.6

Minimum 85

-

Ammonia

lbs/day

14

40

34%

Total Suspended Solids (TSS)

lbs/day

79.3

1,001

8%

     TSS Percent Removal

%

99.4

Minimum 85

-

Dissolved Oxygen

mg/L

8.7

Minimum 8

-

Nitrite

mg/L

0.2

Report

-

Nitrate

mg/L

1

Report

-

Total Nitrogen

lbs/day

122

377

32%

Total Phosphorus

mg/L

1.6

5

32%

1 Summer months include May 1 through October 31.

2 Period analyzed includes January 1, 2009 through December 31, 2013.

3 Permit limits as specified in the TDEC National Pollutant Discharge Permit (NPDES) for TN0028827 effective November 1, 2010.

 

Table 2 - Winter Discharge4


 

Effluent Parameters

Units

Monthly Average 5

Permit Limit 6

Discharge Percentage of NPDES Permit

CBOD5

lbs/day

65

1,001

7%

CBOD5Percent Removal

%

99.5

Minimum 85

-

Ammonia

lbs/day

3.6

150

2.4%

Total Suspended Solids (TSS)

lbs/day

96

3,002

3%

TSS Percent Removal

%

99.2

Minimum 85

-

Dissolved Oxygen

mg/L

8.5

Minimum 8

-

Nitrite

mg/L

0.1

Report

-

Nitrate

mg/L

1.1

Report

-

Total Nitrogen

lbs/day

170

Report

-

Total Phosphorus

lbs/day

80

Report

-

4Winter months include January 1 through April 30 and November 1 through December 31.

5Period analyzed includes January 1, 2009 through December 31, 2013.

6Permit limits as specified in the TDEC National Pollutant Discharge Permit (NPDES) for TN0028827 effective November 1, 2010.

 

 

after UV treatmentThe City also routinely monitors the effluent to ensure it is safe for smaller organisms to live in an environment dominated by WRF effluent. Through these quarterly tests conducted by a third-party laboratory, the City must show that 100 percent of the organisms survive for a 7-day period. In the two tests that have occurred in 2014 (January through March and April through June), the City passed these tests with the required 100 percent survival rate.

The City also conducts annual macroinvertebrate testing in the Harpeth River, both upstream and downstream of the WRF outfall, to ensure water quality is not being degraded by the discharge of WRF effluent. This testing has occurred annually since 2009 and has not shown trending signs of degradation from habitat conditions that are observed upstream of the outfall

  1. Does the Harpeth River meet state water qualitClose up of UV treated watery standards that protect public health and wildlife?
    The Draft 2014 303(d) list, a list published by TDEC, identifies waterbodies within the State of Tennessee that are impaired for certain pollutants. The Harpeth River stretch inside the City of Franklin is impaired for total phosphorus and low dissolved oxygen.Due to the impaired status of the Harpeth River, the EPA developed the Total Maximum Daily Load (TMDL) for the Harpeth River that identifies the maximum levels of pollutants that can be discharged into the river without causing adverse effects. This TMDL identifies loadings into the river from all sources within the Harpeth River watershed, not just the City of Franklin’s WRF. Sources of pollution can discharge to the river from rainfall runoff from roads, cattle farming, agriculture fields and surrounding wildlife and other permitted dischargers into the Harpeth River. The TMDL considers loadings from each of these sources and controls the amount that can enter the river.  Because of this, the City's WRF is not the sole reason the Harpeth River is listed as impaired. however, through the IWRP, the projects the City undertakes to improve existing infrastructure and expansion will occur in accordance with the TMDL limiting the amount of nutrients discharged into the river.

     

  2. Do the options chosen in the IWRP ensure the river meets water quality standards downstream from the City? If so, why does the HRWA website assert the City puts more pollution in the river than current permits allow?
    In 2004, the EPA created a Total Maximum Daily Load (TMDL) for the Harpeth River. This TMDL, created for organic enrichment and low dissolved oxygen, outlines the maximum amount of a pollutant that the Harpeth River can receive and still safely meet water quality standards for its designated uses. The IWRP process that began in 2009 used these maximum loadings that are allowed into the river, even during expansions of the WRF. This means that all projects, from converting septic systems to sewer service to expanding the WRF, will not exceed those limits set forth in the TMDL.  The City considered this document to be the upper bounds by which all projects could discharge into the Harpeth River. So, as projects are planned for the future, pollutant levels will not exceed beyond what is allowed.

Proposed Upgrades to Water Plant

  1. I’ve heard that Franklin is planning on doubling the size of its water treatment plant. Will withdrawing more water reduce the City’s wastewater dilution even more?
    The City is not planning to double the size of its water treatment plant. The City is moving forward with plans to upgrade the facility with a slight increase in capacity from 2.1 MGD to 2.6 MGD. This increase in capacity is directly related to the sizing of standard equipment. Even if the City intended to double the size of the plant, this would not impact the withdrawal framework. Withdrawal is established through a permit with TDEC and is not affected by plant capacity.

  2. Why not buy all our drinking water from HVUD?  Is there enough water in the Harpeth to continue to have a drinking water plant?

    This is a question that we have examined repeatedly. The short answer is that it does make sense for the City to preserve our treatment capabilities for several reasons:

    The City benefits from a diversified water source. Most cities do not have the benefit of multiple sources of drinking water supply. While the Harpeth can provide between 25-30 percent of our needs in a given year, this is extremely meaningful in the event of crisis. The City can produce water at a lower cost than it can purchase water. Because of the City’s ability to produce water at a lower cost, City ratepayers have experienced rate increases at about half the rate they would have otherwise. The City’s withdrawal of water can and is accomplished in a manner that is sensitive to the health of the river. The City’s withdrawal of water from the Harpeth is heavily regulated. The withdrawal is limited to a relatively small fraction of the flow and is completely eliminated when the river is in a low flow condition. The City’s 114 million gallon reservoir helps manage supply needs during dry weather conditions. Over the course of a year, the City’s withdrawal from the river equates to approximately one percent of the Harpeth’s annual flow.

Wastewater Treatment CapacityWWTP

  1. Why does the City of Franklin need a second wastewater treatment plant upstream of the water plant?

    The City is evaluating the potential for a second Water Reclamation Facility to accommodate the growth the City of Franklin is experiencing utilizing the most economically feasible alternatives for our customers and citizens. Wastewater infrastructure is vital to any city’s growing population and must be planned and designed on the forefront of expanding sewer services. If a new WRF is deemed the most economically feasible alternative, a high level of advanced treatment will be implemented to ensure high quality effluent is entering the Harpeth River that will be safe to all users.

  2. Is the City planning to use treated wastewater for direct drinking water

    No. The City is not planning on using treated wastewater for direct drinking water. The City is considering what is referred to as indirect potable reuse (IPR). It is important to understand the meaning of IPR, which has been in place for years all across the country, including Middle Tennessee. Indirect potable reuse typically occurs on an unplanned or incidental basis when an upstream community discharges treated wastewater, which is then withdrawn by a downstream community for drinking water treatment. Advanced treatment processes being considered for our Water Reclamation Facility upgrade allow us to consider purposeful IPR in which highly treated municipal wastewater would be discharged to the Harpeth River, then later withdrawn and pumped to a 114 million gallon raw water reservoir. The environmental buffers of the river and the reservoir coupled with these advanced treatment processes allow us to consider this concept, which will be thoroughly evaluated to ensure its appropriateness for our community.