Summary of Ohio's Water Reuse Guideline or Regulation for Onsite Non-potable Water Reuse

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 Onsite Collected Waters.

On this page:

• Technical basis
• Background on NSF/ANSI Standard 350
• Types of onsite non-potable reuse approved for use in Ohio
• Water reuse category/type
• Additional context and definitions
• Onsite non-potable reuse specifications (table)
• Upcoming state law or policy
• References
• Disclaimer

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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 Ohio, onsite non-potable water reuse onsite non-potable water reuse The use of treated onsite collected waters for non-potable purposes at the single-building or district scale. This reuse application excludes the use of recycled water from a centralized treatment and distribution system for landscape irrigation or commercial uses. include surface and sub-surface landscape irrigation. The source of water (onsite collected waters) onsite collected waters Water sources generated within or surrounding a building, residence, or district. Other terms referring to this source of water include onsite collected stormwater or rainwater, greywater, blackwater, air conditioning condensate, and foundation water. is specified by the state as gray water. 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

Ohio approves the onsite non potable reuse of gray water generated from a building or dwelling for surface or sub-surface landscape irrigation (Ohio Admin. Code 3701:29). 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.  Onsite non-potable gray water recycling systems treat and reuse gray water discharged from lavatories, bathtubs, showers, clothes washers and laundry sinks that does not contain food wastes or bodily wastes. Ohio categorizes grey water recycling systems (GWRS) into four types according to end use application and system requirements. The most stringent, Type 4 GWRS, must meet NSF/ANSI Standard 350 requirements and has a discharge limit of 60-1,000 gallons of treated gray water per day. The remaining types do not have explicit treatment requirements or water quality specifications other than application requirements and discharge limits: ≤60 gallons/day (Type 1), 60-1,000 gallons/day (Type 2) and ≤1,000 gallons per day (Type 3). The technical basis for the GWRS (Types 1-3) requirements are not explicitly specified.

Background on NSF/ANSI Standard 350

The National Sanitation Foundation/American National Standards Institute (NSF/ANSI) was originally adopted in 2011 and includes requirements for testing onsite residential and commercial water reuse treatment systems. NSF/ANSI 350 includes requirements for two categories of facilities: residential (up to 1,500 gallons per day) and commercial (systems exceeding 1,500 gallons per day); and four different types of influent: (1) combined black and gray water; (2) gray water only; (3) bathing water only; and (4) laundry water only. The standard covers general non-potable reuse applications, including surface and subsurface irrigation and toilet and urinal flushing. There are two categories of effluent criteria that vary slightly: Class R for single family residential and Class C for multi-family residential and commercial. These effluent quality criteria were developed using the currently existing guidelines codes and regulations, with the goal of meeting the majority of existing codes (although the guidelines do not meet all state codes). Class R includes E. coli water quality requirements not to exceed 14 MPN/100 mL geometric mean and 240 MPN/100 mL single sample maximum and Class C includes E. coli water quality requirements not to exceed 2.2 MPN/100 mL geometric mean and 200 MPN/100 mL single sample maximum.  

Types of onsite non-potable reuse approved for use in Ohio

Ohio Admin. Code 3701:29 defines the following approved onsite non-potable uses of gray water treated by gray water recycling systems:

• Surface and subsurface landscape irrigation of gardens, lawns and landscape plants, food crops, green roofs and living walls (Type 4)
• Subsurface landscape irrigation of gardens, lawns and landscape plants (Type 1, 2)
• Subsurface irrigation of food crops except root crops or crops that have edible portions that contact the gray water (Type 1, 2)

No specific reuse applications are defined for Type 3 gray water recycling systems. 

Water reuse category/type

Ohio Admin. Code 3701:29 categorizes gray water recycling systems (GWRS) into four types: 

• Type 1 GWRS: must be applied at least 25 feet from food crops with exposed edible portions and a Type 1 GWRS must only discharge ≤60 gallons per day. No gray water may be held in a tank or holding structure longer than 24 hours.
• Type 2 GWRS: The treated graywater must be applied at least 25 feet from food crops with exposed edible portions and a Type 2 GWRS must only discharge between 60 and 1,000 gallons per day. No gray water may be held in a tank or holding structure longer than 24 hours.
• Type 3 GWRS: A Type 3 GWRS must be designed in accordance with Ohio Admin. Code 3701:29-15 to meet general soil absorption standards for household sewage disposal systems. It may be designed for continual use and is limited to a design flow of 1,000 gallons per day.
• Type 4 GWRS: A Type 4 GWRS must include a pretreatment component or treatment train that meets NSF/ANSI Standard 350 requirements. A Type 4 GWRS must only discharge between 60 and 1,000 gallons per day. Gray water may be stored more than 24 hours with pretreatment. 

Additional context and definitions

Oklahoma defines gray water as “wastewater discharged from lavatories, bathtubs, showers, clothes washers, and laundry sinks that does not contain food wastes or urine or fecal matter” (Ohio Admin. Code 3701:29). In Ohio, bodily waste is considered to be human urine or fecal matter and is regulated by the Ohio Department of Health under Ohio Admin. Code 3701:29. 

Onsite non-potable reuse specifications

Summary of Ohio's Non-potable Reuse Specifications

Sources = Ohio Admin. Code 3701:29-17
GWRS = gray water recycling system

Upcoming state law or policy

No upcoming onsite non-potable reuse regulations were found for Ohio.

References:

Clean Water Act, 33 U.S.C. §§ 1251 et seq.

Onsite Residential and Commercial Water Reuse Treatment Systems, NSF/ANSI Standard 350.

Sewage Treatment Systems, Ohio Admin. Code 3701:29.

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Disclaimers

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.