Summary of New Mexico's Water Reuse Guideline or Regulation for Agriculture
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 agriculture approved for use in New Mexico
- Water reuse treatment category for agriculture
- Additional context and definitions
- Water reuse for agriculture 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 New Mexico, water reuse for water reuse for agricultureThe use of recycled water to land to assist in the production of both commercially and non-commercially processed food crops consumed by humans or livestock and non-food crops. Includes pasture for milking and non-milking animals, fodder, fiber, and seed crops, vineyards, orchards, ornamental nursery stock, Christmas trees, and silviculture. Excludes consumption by livestock, onsite non-potable reuse, and landscaping. includes food crops when there is no contact between the edible portion of the crop and the wastewater; fodder, fiber and seed crops for milk-producing and non-milk-producing animals; sod farms; pasture for milking cows or goats; and forest trees. 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 domestic wastewater. This 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
The New Mexico Environment Department (NMED) provides guidance for above ground reuse of reclaimed domestic wastewater to “ensure protection of public health and the environment” (NMED, 2007). 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 relevant rule requirements under the Food Safety Modernization Act (FSMA) (124 Stat. 3885). Class 1A reclaimed wastewater is approved for the irrigation of food crops where there is no contact with the edible portion of the crop in areas where public access is likely; specific restrictions on public access are not provided. Class 2 and Class 3 reclaimed wastewaters are approved for agricultural irrigation reuse applications in areas where public access is restricted with correspondingly less stringent requirements for treatment and disinfection for Class 3 when compared to Class 2 and Class 1A. Treatment requirements and performance standards are applied for the removal of microbial contaminants, chemicals and other relevant indicators related to agriculture and are summarized in the table. New Mexico developed their specifications and/or removals of microbial contaminants, chemicals and other relevant indicators based on a comparison to other state reuse approaches (Colorado, Arizona, Texas, Washington and Florida), NPDES limits (40 C.F.R. part 122) and related New Mexico surface water limits (N.M. Code R. § 20.6.4).
Water reuse for agriculture approved for use in New Mexico
NMED (2007) defines the following approved water reuse for agriculture:
- Food crops when there is no contact between the edible portion of the crop and the wastewater (Class 1A)
- Fodder, fiber and seed crops for milk-producing animals (Class 2)
- Sod farms (Class 2)
- Pasture for milking cows or goats (Class 2)
- Fodder, fiber and seed crops for non-milk-producing animals (Class 3)
- Forest trees (silviculture) (Class 3)
Water reuse treatment category for agriculture
The various classes of reclaimed water treatment are defined by their respective treatment requirements and applicable performance standards. The respective treatment requirements are briefly summarized regarding water reuse for agriculture (NMED, 2007):
- Class 1A reclaimed wastewater is suitable only for irrigation of food crops when there is no contact between the edible portion of the crop and the wastewater. Spray irrigation of food crops is prohibited. Application of Class 1A reclaimed water does not require restrictions on public access and exposure. It requires a minimum of treatment to remove colloidal organic matter, color and other substances that interfere with disinfection plus disinfection. Requirements for treatment and disinfection (measurements of fecal coliforms) are more stringent when compared to Class 2 and Class 3.
- Class 2 reclaimed wastewater is suitable for purposes in which public access and exposure is restricted. It requires a minimum of conventional secondary wastewater treatment plus disinfection. Requirements for treatment and disinfection (single sample maximum for total suspended solids and measures of fecal coliforms) are more stringent when compared to Class 3.
- Class 3 reclaimed wastewater is suitable for purposes in which public access and exposure is restricted. It requires a minimum of conventional secondary wastewater treatment plus disinfection.
Additional context and definitions
In New Mexico, reclaimed water is defined as “domestic wastewater that has been treated to the specified levels for the defined uses set forth in this guidance document and other applicable local, state, or federal regulations” (NMED, 2007). Domestic wastewater is defined as “wastewater containing human excreta and water-carried waste from typical residential plumbing fixtures and activities, including but not limited to wastes from toilets, sinks, bath fixtures, clothes or dishwashing machines and floor drains” (NMED, 2007).
New Mexico requires all municipal reclaimed wastewater piping, valves and outlets to be colored purple to differentiate it from piping or fixtures used for potable or other water (NMED, 2007). Reclaimed wastewater systems should have no indirect or direct cross connections with potable water systems. Signs in English and Spanish stating “NOTICE – THIS AREA IS IRRIGATED WITH RECLAIMED WASTEWATER – DO NOT DRINK” must be placed at the entrance to areas receiving reclaimed wastewater and other locations where public access may occur.
Water reuse for agriculture specifications
Summary of New Mexico's Water Reuse for Agriculture Specifications
| Recycled Water Class/Category | Source Water Type | Water Quality Parameter | Specification | Sampling/Monitoring Requirements (Frequency of monitoring; site/ location of sample; quantification methods)* |
|---|---|---|---|---|
|
Class 1A Reclaimed Water (Irrigation of food crops) |
Domestic wastewater |
5-day biochemical oxygen demand (BOD5) |
10 mg/L (30-day average) 15 mg/L (single sample maximum) |
Minimum of 6-hour composite and 3 tests per week for major WWTPa and 1 test per 2 weeks for minor WWTP |
|
Turbidity |
3 NTU (30-day average); 5 NTU (single sample maximum) |
Continuous monitoring |
||
|
Fecal coliformb |
5 organisms/100 mL (30-day average) 23 organisms/100 mL (single sample maximum) |
Grab sample at peak flow; 3 tests per week for major WWTPa and 1 test per week for minor WWTP |
||
|
Total residual chlorine (TRC) or UV transmissivity |
None, monitor only |
Grab sample or reading at peak hourly flow; Record values at peak hourly flow when fecal coliform samples are collected |
||
|
Nitrogen |
Not specified |
Not specified |
||
|
Class 2 Reclaimed Water (Irrigation of sod farms, fodder, fiber and seed crops for milk-producing animals and pasture for milking cows or goats) |
Domestic wastewater |
5-day biochemical oxygen demand (BOD5) |
30 mg/L (30-day average) 45 mg/L (single sample maximum) |
Minimum of 6-hour composite and 1 test per week for major WWTPa; Grab sample and 1 test per month for minor WWTP |
|
Total suspended solids (TSS) |
30 mg/L (30-day average) 45 mg/L (single sample maximum) |
|||
|
Fecal coliformb |
200 organisms/100 mL (30-day average) 400 organisms/100 mL (single sample maximum) |
Grab sample at peak hourly flow; 1 test per week for major WWTPa; 1 test per month for minor WWTP |
||
|
Total residual chlorine (TRC) or UV transmissivity |
None, monitor only |
Grab sample or reading at peak hourly flow; Record values at peak hourly flow when fecal coliform samples are collected |
||
|
Nitrogen |
If reclaimed wastewater contains >10 mg/L, the reuse permittee must submit a Land Application Data Sheet (LADS) to ensure they will not exceed loading of 200 lbs/acre/year |
Not specified |
||
|
Class 3 Reclaimed Water (Irrigation of forest trees (silviculture), fodder, fiber and seed crops for non-milk-producing animals) |
Domestic wastewater |
5-day biochemical oxygen demand (BOD5) |
30 mg/L (30-day average) 45 mg/L (single sample maximum) |
Minimum of 3-hour composite and 1 test per week for major WWTPa; Grab sample and 1 test per month for minor WWTP |
|
Total suspended solids (TSS) |
30 mg/L (30-day average) 75 mg/L (single sample maximum) |
|||
|
Fecal coliformb |
1,000 organisms/100 mL (30-day average) 5,000 organisms/100 mL (single sample maximum) |
Grab sample at peak hourly flow; 1 test per week for major WWTPa; 1 test per month for minor WWTP |
||
|
Total residual chlorine (TRC) or UV transmissivity |
None, monitor only |
Grab sample or reading at peak hourly flow; Record values at peak hourly flow when fecal coliform samples are collected |
||
|
Nitrogen |
If reclaimed wastewater contains >10 mg/L, the reuse permittee must submit a Land Application Data Sheet (LADS) to ensure they will not exceed loading of 200 lbs/acre/year |
Not specified |
Source= NMED (2007), N.M. Code R. § 20.6.2.3109.C(3)
* 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.
a A “major” WWTP has a maximum design capacity of 1 million gallons or more per day. A “minor” WWTP has a maximum design capacity of less than 1 million gallons per day.
bE. coli may be used in place of fecal coliform as an indicator organism once an equivalency has been established.
Upcoming state law or policy
NMED has proposed supplemental requirements for water reuse (20.6.8 NMAC) including produced water and will accept public comment through December 1, 2023.
References
Clean Water Act, 33 U.S.C. §§ 1251 et seq.
EPA-Administered Permit Programs: The National Pollutant Discharge Elimination System (NPDES), 40 C.F.R. part 122.
Food Safety Modernization Act (FSMA), 124 Stat. 3885.
New Mexico Environment Department (NMED). 2007. Ground water quality bureau guidance: Above-ground use of reclaimed domestic wastewater, New Mexico Environment Department. 2007.
Secretary Approval, Disapproval, Modification or Termination of Discharge Permits, and Requirement for Abatement Plans, N.M. Code R. § 20.6.2.3109.C(3).
Standards for Interstate and Intrastate Surface Waters, N.M. Code R. § 20.6.4.
Please contact us at [email protected] 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.