Summary of Arkansas’ 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 Rainwater Collected Onsite.

• Technical basis
• Onsite non-potable water reuse approved for use in Arkansas
• 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 Arkansas, 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. applications include water closet and urinal flushing. The source of water (rainwater collected onsite) rainwater collected onsite Precipitation collected at the district or regional scale is classified separately under 'stormwater.' is specified by the state as rainwater. 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

Arkansas approves the use of harvested rainwater for onsite non-potable water reuse applications, including for water closet and urinal flushing (AR § Code 17-38-201). Rainwater collection and distribution systems must be designed with the appropriate cross-connection safeguards by a professional engineer licensed in Arkansas and comply with the Arkansas Plumbing Code (AR § Code 17-38-201). 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. A permit is required for the construction, installation, repair, or alteration of non-potable water systems (APC, 2018). Treatment requirements and performance standards are applied for the removal of debris, microbial contaminants, chemicals, and other relevant indicators related to onsite non-potable water reuse 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.

Onsite non-potable water reuse applications approved for use in Arkansas

The Arkansas Plumbing Code (2018) defines the following specific onsite non-potable water reuse applications for treated rainwater from non-potable rainwater collection and distribution systems:

• Water closet and urinal flushing

Additional onsite non-potable water reuse applications for treated rainwater from rainwater collection and distribution systems are not specified.

Water reuse treatment category/type

Arkansas does not assign harvested rainwater used for onsite non-potable water reuse to a category or class, but “nonpotable water for each end use application shall meet the minimum water quality requirements as established for the intended application by the laws, rules and ordinances applicable in the jurisdiction” (APC, 2018).

Treatment requirements are provided for harvested rainwater in Arkansas. Briefly, the treatment requirements include:

• Filtration: All rainwater collection and distribution systems must include filtration mechanisms for rainwater in the form of a debris excluder and automatic first-flush diverter, both installed with proper design for clean-out (APC, 2018). Collected rainwater must be further filtered as required for the intended end use (APC, 2018). Specifically, non-potable water utilized for water closet and urinal flushing must be filtered by a 100-micron or finer filter (APC, 2018). All filtration must have a mechanism to indicate servicing or replacement as well as be installed with a shutoff valve immediately upstream and downstream to allow for maintenance (APC, 2018).
• Disinfection: Arkansas requires harvested rainwater be disinfected as necessary to meet water quality requirements specific for the intended onsite water reuse application, including those provided in the table (APC, 2018).

Additional context and definitions

In Arkansas, collection of rainwater should be limited to above-ground waterproof roofing surfaces. Collection surface, roof gutters, and downspouts must be constructed from approved materials as to meet the rainwater quality for the desired end use (APC, 2018). Downspouts and leaders must be connected to a debris excluder or equivalent device that is designed to remove leaves, sticks, pine needles and similar debris to prevent such from entering the storage tank (APC, 2018). The roof gutters and downspouts must have a continuous slope greater or equal to an eighth of an inch per foot towards the collection inlets and not permit the pooling of water at any point along the slope (APC, 2018). Roof gutters and downspouts must be sized based on local rainfall rates and flow-rate from roof surface (APC, 2018). Cleanouts must be provided in the rainwater collection system to allow access to all filters, flushes, pipes and downspouts (APC, 2018).

Arkansas requires specific design elements when implementing rainwater collection practices. Non-potable water storage tanks should be protected from direct sunlight through one of the following methods: (1) outer tank materials made of UV resistant materials, (2) specially constructed sun barriers or (3) tank installation in garages, crawl spaces, or sheds (APC, 2018). Non-potable water storage tanks must be made with durable, nonabsorbent and corrosion-resistant materials compatible with any disinfection system to maintain water quality, among other specifications (APC, 2018). All non-potable water storage tanks must be made identifiable with signage with the words “Nonpotable water is utilized for [application name]. CAUTION: NONPOTABLE WATER – DO NOT DRINK.” (APC, 2018).

Arkansas recommends the use of ASTM E2727 to identify which, if any, site conditions affect the quality of collected raw rainwater and determine if the raw rainwater needs treatment for the intended end use or the site conditions make the water unsuitable for the end uses in consideration (APC, 2018).

Onsite non-potable water reuse specifications

Summary of Arkansas's Onsite Non-potable Water Reuse Specifications

Source = APC (2018)

* 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.

Upcoming state law or policy

No upcoming onsite non-potable water reuse regulations related to rainwater were found for Arkansas.

References:

Arkansas Plumbing Code (APC). 2018. Chapter 13: Nonpotable Water Systems.

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

Regulation by State Board of Health: Powers and duties generally, Ark. Code § 17-38-201 (2017).

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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.