Summary of Tennessee's Water Reuse Guideline or Regulation for Landscaping
This page is part of the EPA’s REUSExplorer tool, which summarizes the different state level regulations or guidelines for water reuse for a variety of sources and end-uses.
The source water for this summary is Treated Municipal Wastewater.
On this page:
- Technical basis
- Water reuse for landscaping approved for use in Tennessee
- Water reuse treatment category for landscaping
- Additional context and definitions
- Landscaping reuse specifications (table)
- Upcoming state law or policy
- References
- Disclaimer
This page is a summary of the state’s water reuse law or policy and is provided for informational purposes only. Please always refer to the state for the most accurate and updated information.
In Tennessee, water reuse for landscapingThe use of recycled water on land to assist in the irrigation of vegetation in residential and non-residential areas. Includes impoundments to store water for irrigation , ornamental vegetation, parks, school yards, sporting facilities (including golf courses), private gardens, roadsides and greenbelts, and cemeteries. Excludes irrigation of areas used for agriculture, commercial reuse applications, or any centralized non-potable reuse. reuse applications include maintenance of landscapes during periods of insufficient rainfall, irrigation of ornamental vegetation and irrigation of athletic fields, among others. The source of water treated municipal wastewater Treated wastewater effluent discharged from a centralized wastewater treatment plant of any size. Other terms referring to this source of water include domestic wastewater, treated wastewater effluent, reclaimed water, and treated sewage. is specified by the state as reclaimed water from non-discharging wastewater systems. Tennessee uses the term non-discharging wastewater systems to describe systems in which wastewater is treated to meet the minimum criteria with the intent of being used as reclaimed water for non-potable purposes. The write-up uses state terms when discussing sources or uses of water that may differ from the Regulations and End-Use Specifications Explorer’s (REUSExplorer’s) terms.
Technical basis
Tennessee approves the reuse of treated municipal wastewater for landscaping applications including maintenance of landscapes during periods of insufficient rainfall, irrigation of ornamental vegetation and irrigation of athletic fields, among others (TN Code § 0400-40-06). All applicable provisions of the Clean Water Act (CWA) (33 U.S.C. §§ 1251 et seq.), including its implementing regulations, must be met in addition to any state water quality standards. Treated municipal wastewater is subject to specifications under Tennessee’s State Operating Permits (SOPs) which authorize operation of non-discharging sewerage systems, given compliance with permit conditions (TN Code § 0400-40-06). Treatment requirements and performance standards are applied for the removal of debris, chemicals and other relevant indicators related to landscaping and are summarized in the table. The technical basis for developing the specifications and/or removal of debris, microbial contaminants, chemicals and other relevant indicators is not explicitly specified.
Water reuse for landscaping approved for use in Tennessee
Tennessee (TN Code § 0400-40-06) approves of these landscaping reuse applications for recycled treated municipal wastewater:
- Maintenance of landscapes during periods of insufficient rainfall
- Irrigation of ornamental vegetation
- Irrigation of athletic fields
Additional landscaping reuse applications for collected treated municipal wastewater are not specified.
Water reuse treatment category for landscaping
Tennessee does not assign recycled treated municipal wastewater used for landscaping to a category or class. For non-discharging wastewater systems, Tennessee describes that “facilities that treat municipal and/or domestic wastewater, but do not discharge into waters of the state, shall be limited in terms of BOD5 and other pollutants such as NH3-N, NO3-N, and fecal coliform as necessary. Limits shall be set in such a way to assure efficient operation and protection of groundwater” (TN Code § 0400-40-05-.09).
TN Code § 0400-40-06-.10 provides parameters for the use of treated municipal wastewater for unrestricted urban reuse, which includes the irrigation of athletic fields and landscaping where public access is not restricted. In addition, parameters are present for restricted urban reuse where public access is controlled by physical or institutional barriers (e.g., fencing, advisory signage or temporal access restrictions). Water quality parameters are summarized in the table for irrigation and unrestricted and restricted urban reuse.
TN Code § 0400-40-03-.03 provides parameters for the use of treated municipal wastewater for irrigation. The following parameters do not have a provided quantitative criteria value.
- Dissolved oxygen: There shall always be sufficient dissolved oxygen present to prevent odors of decomposition and other offensive conditions.
- Temperature: The temperature of the water shall not interfere with its use for irrigation purposes.
- Hardness or mineral compounds: The hardness of or the mineral compounds contained in the water shall not impair its use for irrigation.
- Solids, floating materials, and deposits: There shall be no distinctly visible solids, scum, foam, oily slick, or the formation of slimes, bottom deposits or sludge banks of such size or character that impair the usefulness of water for irrigation purposes.
- Toxic substances: The waters shall not contain toxic substances whether alone or in combination with other substances which will produce toxic conditions that adversely affect the quality of the waters for irrigation.
- Other pollutants: The waters shall not contain other pollutants in quantities which may be detrimental to the waters used for irrigation.
Additional context and definitions
Tennessee defines the reuse of reclaimed water as “the application of reclaimed wastewater of sufficient quality to be reused in non-discharging wastewater systems in a manner protective of human health and the environment” (TN Code § 0400-40-06-.02). Tennessee uses the term non-discharging wastewater systems to describe systems in which wastewater is treated to meet the minimum criteria with the intent of being used as reclaimed water for non-potable purposes (TN Code § 0400-40-06-.02).
For end uses of reclaimed water that fall under non-potable reuse, Tennessee requires applicants seeking authorization to provide these materials engineering design criteria, provide a Reclaimed Wastewater Management Plan (RWMP), end user service agreements and demonstrated availability of reuse alternatives. All piping of non-potable water must be colored purple.
Tennessee states that treated municipal wastewater must be applied at a calculated agronomic application rate which varies by density of crops, season, ambient weather conditions, shade coverage and characteristics of reclaimed wastewater. Agronomic application rate is defined as “the application of reclaimed wastewater to meet nutrient or hydraulic uptake needs of food crops, feed crops, cover crops, or vegetation grown on land, the latter category including but not limited to athletic fields and ornamental landscaping” (TN Code § 0400-40-06). To ensure there is no unpermitted discharge, Tennessee requires that treated municipal wastewater used for irrigation must not be applied in excess of the evaporation rate plus the uptake of the vegetation in the immediate distribution area (TN Code § 0400-40-06.10).
Tennessee defines treatment requirements for non-potable reuse purposes in an urban or suburban setting based on public access to applied treated municipal wastewaters (TN Code § 0400-40-06-.10).
- Unrestricted urban reuse: “non-potable reuse of reclaimed wastewater in municipal or suburban settings that is of such quality that public access is not restricted, such as irrigation for athletic fields, landscaping, or other approved ‘purple pipe’ residential uses.”
- Restricted urban reuse: “the non-potable reuse of reclaimed wastewater in municipal or suburban settings that is of such quality that public access is controlled or restricted by physical or institutional barriers, such as fencing, advisory signage, or temporal access restrictions.”
Landscaping reuse specifications
Summary of Tennessee’s Landscaping Reuse Specifications
| Recycled Water Class/Category (Approved Uses) | Source Water Type | Water Quality Parameter | Specification | Sampling/Monitoring Requirements (Frequency of monitoring; site/ location of sample; quantification methods)a,b |
|---|---|---|---|---|
|
Irrigation (TN Code § 0400-40-03-.03) |
Treated municipal wastewater |
Dissolved oxygen |
Sufficient dissolved oxygen to prevent odors of decomposition, among other offensive conditions. |
Not specified |
|
pH |
6.0 to 9.0 Not to fluctuate more than 1.0 unit in this range over a period of 24 hours. |
Weekly |
||
|
Solids, floating materials and deposits |
No distinctly visible solids, scum, foam, oily slick, or the formation of slimes, bottom deposits or sludge banks |
Not specified |
||
|
Unrestricted urban access (TN Code § 0400-40-06-.10) |
Treated municipal wastewater |
pH |
6.0 to 9.0 Not to fluctuate more than 1.0 unit in this range over a period of 24 hours. |
Weekly Measured at the effluent sampling point of the pump station into the reclaimed water distribution system or as otherwise indicated in the SOP or NPDES permit. |
|
CBOD5 or NH3-N |
10 mg/L CBOD5 or 5 mg/L NH3-N |
Weekly Measured at the effluent sampling point of the pump station into the reclaimed water distribution system or as otherwise indicated in the SOP or NPDES permit. |
||
|
NTU or TSS |
5 NTU or 5 mg/L TSS |
Continuous NTU or daily TSS Measured at the effluent sampling point of the pump station into the reclaimed water distribution system or as otherwise indicated in the SOP or NPDES permit. |
||
|
Escherichia coli |
23 CFU/100mL |
Measured at point of release from reclamation system. Once per week measurement frequency for ≤100,000 gal/week application volume. Twice per week measurement frequency for ≥100,000 gal/week application volume. Daily measurement frequency for ≥1,000,000 gal per week application volume. |
||
|
Chlorine residualc |
Minimum of 1 mg/L |
Measured at point of release from reclamation system. Once per week measurement frequency for ≤100,000 gal/week application volume. Twice per week measurement frequency for ≥100,000 gal/week application volume. Daily measurement frequency for ≥1,000,000 gal per week application volume. |
||
|
Restricted urban access (TN Code § 0400-40-06-.10) |
Treated municipal wastewater |
pH |
6.0 to 9.0 |
Weekly Measured at the effluent sampling point of the pump station into the reclaimed water distribution system or as otherwise indicated in the SOP or NPDES permit. |
|
CBOD5 or NH3-N |
30 mg/L CBOD5 or 10 mg/L NH3-N |
Weekly Measured at the effluent sampling point of the pump station into the reclaimed water distribution system or as otherwise indicated in the SOP or NPDES permit. |
||
|
TSS |
30 mg/L |
Continuous NTU or daily TSS Measured at the effluent sampling point of the pump station into the reclaimed water distribution system or as otherwise indicated in the SOP or NPDES permit. |
||
|
E. coli |
200 CFU/100mL |
Measured at point of release from reclamation system. Once per week measurement frequency for ≤100,000 gal/week application volume. Twice per week measurement frequency for ≥100,000 gal/week application volume. Daily measurement frequency for ≥1,000,000 gal per week application volume. |
||
|
Chlorine residualc |
Minimum of 1 mg/L |
Measured at point of release from reclamation system. Once per week measurement frequency for ≤100,000 gal/week application volume. Twice per week measurement frequency for ≥100,000 gal/week application volume. Daily measurement frequency for ≥1,000,000 gal per week application volume. |
Source = TN Code § 0400-40-03-.03 and TN Code § 0400-40-06-.10
a Information about sampling and monitoring requirements such as frequency, site and quantification methods not specifically listed in the table was not explicitly specified in the State-specific regulations.
b The monitoring frequency may be increased due to special circumstances in the NPDES permit or SOP, as agreed upon in the end user service agreement, or as agreed by the reclaimed wastewater provider.
c Chlorine residual limits apply only upon failure to comply with E. coli limits ≥10% of the time for the previous month.
Upcoming state law or policy
No upcoming regulations pertaining to landscaping reuse applications were found for Tennessee.
References
Clean Water Act, 33 U.S.C. §§ 1251 et seq.
Division of Water Pollution Control, TN Code § 0400-40.
Food Safety Modernization Act (FSMA), 124 Stat. 3885.
General Water Quality Criteria, TN Code § 0400-40-03-.03 (2019).
Permits, Effluent Limitations and Standards, TN Code § 0400-40-05.
State Operating Permits, TN Code § 0400-40-06 (2022).
Tennessee Department of Environment and Conservation (TDEC). 2023a. ARP Competitive Grant Workshop Series: Water Reuse.
Water Quality State Operating Permits (SOP).
Please contact us at waterreuse@epa.gov if the information on this page needs updating or if this state is updating or planning to update its laws and policies and we have not included that information on the news page.