Summary of Environmental Law in Mexico

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• 9. Protection and Management of Water Resources
• 9.1. Establishing Water Discharge Standards
• 9.2. Point Sources
• 9.3. Non-Point Sources
• 9.4. Protection of Safe Drinking Water
• 9.5. Protection of Groundwater
• 9.6. Water Quantity and Use
• 9.7. Protection of Fresh Water Ecosystems
• 9.8. Liability and Enforcement

Summary of the Legal Regime

Article 27 of the Political Constitution of the United States of Mexico (hereinafter Mexican Constitution), which confers inalienable rights of ownership over all national waters to the Nation, provides the foundation for water protection and management laws. In order for hydraulic resources to be exploited, the federal government, through the National Water Commission, may grant water use concessions to private parties. The current legal framework governing water pollution control is set forth in two laws: the General Law of Ecological Balance and Environmental Protection (Ley General del Equilibrio Ecológico y la Protección al Ambiente) (hereinafter Ecology Law), which establishes general criteria pertaining to water pollution prevention and control, and the National Waters Law (Ley de Aguas Nacionales) which provides a comprehensive legal regime that supports the broader provisions set out in the Ecology Law. The National Waters Law is complemented by an implementing regulation, the Regulation under the National Waters Law (Reglamento de la Ley de Aguas Nacionales) (hereinafter Water Regulation) and by Official Mexican Standards (Normas Oficiales Mexicanas (NOMs)).

National Water Commission

Administration over water laws is shared by both the federal and the state governments. The National Waters Law has created an independent federal agency, the National Water Commission (Comisión Nacional del Agua (CNA)), which has jurisdiction over hydraulic issues. The CNA is granted jurisdiction over most of the water planning, permitting, management and enforcement issues. The CNA is assisted by a Technical Council that provides policy, fiscal, administrative and scientific advice. In addition, federal, state and local coordinating bodies, known as Basin Councils, made up of public representatives, provide CNA with advice regarding hydraulic policies.

The National Hydraulic Program contains the national policy to be followed by CNA for managing hydraulic resources. Similar to the National Development Plan and the National Environment Plan, the National Hydraulic Program 2001-2006 sets goals through 2025. The Program sets the following national strategies:

• Greater user support to increase efficiency and productivity in irrigation zones;
• Implementation of mechanisms to promote technological change in irrigation systems;
• Incorporation of new irrigation areas, as well as technical support for temporary areas;
• Promotion of extended coverage and quality in drinking water, drainage and sewer services;
• Comprehensive and sustainable use of water in basins and aquifers;
• Promotion of technical, administrative and financial development in the hydraulic sector;
• Consolidated participation of users and organized society in water management and the promotion of a culture of proper water usage; and
• Reduced irrigation and attention to the effects of floods and droughts.

State Agencies

State and municipal authorities are primarily responsible for controlling wastewater discharges into drainage and sewage systems.

9.1 Establishing Water Discharge Standards

General Criteria

The CNA is authorized, with the assistance of the Secretariat of the Environment and Natural Resources (Secretaría del Medio Ambiente y Recursos Naturales (SEMARNAT)), the Secretariat of the Navy (Secretaría de Marina (SM)) and the Health Secretariat (Secretaría de Salud (SSA)), to issue water quality and wastewater discharge standards. Under the general provisions of Article 122 of the Ecology Law, all public, industrial or farming wastewater discharges into any sewage system, watershed, river, riverbed, reservoir or any other hydraulic or wastewater system, that could infiltrate the soil or subsoil, must have the necessary conditions so as to avoid:

1. Polluting the recipient body;
2. Interfering with water purification processes; and
3. Disturbing, impeding or altering the natural function and capacity of riverbeds, basins, aquifers and other water reservoirs owned by the Nation or those of the drainage systems.

Article 8 of the National Waters Law requires that CNA classify national waters according to the types of water bodies, their pollution load, their capacity to dilute and assimilate pollutants and the maximum allowable limit (LMP) for a particular pollutant. In addition, Article 78 of the National Waters Law charges the CNA with establishing quality objectives for national waters and a timetable for achieving those goals. The classification system is used as a basis for issuing permits.

Specific Standards

Pursuant to Article 120 of the Ecology Law, industrial, municipal, farming, wastewater and toxic discharges are subject to federal and state regulation. In addition, all discharges into rivers, sewage systems and other water reservoirs and water flows must meet the requirements set out in the applicable NOMs, as well as the conditions established for discharges. The NOMs provide mandatory sampling and monitoring procedures and are used for bringing administrative enforcement actions.

Specific Conditions Established by the CNA

Besides the discharge standards under the NOMs, the CNA may establish specific discharge standards for industrial facilities, known as "specific discharge conditions", and spell them out in individual permits. Pursuant to Article 89 of the National Waters Law and Article 140 of the Water Regulation, the CNA is required to take into account the NOMs, its own water classification system, third party rights to develop or use the receiving body of water, the restrictions imposed under the National Water Plan (Plan Nacional de Aguas) and other public interest or general health related issues, when establishing specific discharge conditions. See Discharge Permits discussed under section 9.2 "Point Sources".

9.2 Point Sources

Point sources are not defined per se under the National Waters Law or its Regulation. However, all individuals, ejidatarios (common land holders), communities, associations, corporations and other legal entities are required to comply with the comprehensive permitting regime established under the National Waters Law and the Water Regulation. The CNA regulates point sources through: (1) concessions or assignments that grant rights to use or develop water sources and (2) wastewater discharge permits.

Concessions and Allocations

All individuals, corporations and other legal entities, including states and municipalities or sub-state authorities that exploit, use or profit from national waters must obtain a water use concession or allocation from CNA. Industrial use is defined as the utilization of national waters in factories or facilities engaged in the extraction, conservation or transformation of raw materials and minerals and the manufacture or finishing of products, and encompasses all industrial waters used for boilers, cooling, washing, salinization or distillation processes for extraction purposes, as well as those waters used in the generation or transformation of electrical power. An exception applies to household water use and reserves, provided the extraction is manual and does not entail water diversion, contamination or significant reduction in the capacity of the water body at issue. The CNA generally grants concessions on a precedence basis, but may allow bidding where there are several applicants. Concessions may not be granted for either less than five or more than fifty years. Concessionaires are liable for all third party damages that may arise from the use of the concession.

Discharge Permits

All individual and legal entities must obtain permits from the CNA for any continuous, intermittent or unforeseen wastewater discharges into receiving water or soil bodies belonging to the nation, including ground waters. The Water Regulation specifically states that a "receiving body" includes all lands where wastewater is injected or infiltrated that may contaminate the soil or ground waters. Individuals or corporations that carry out discharges are responsible for treating wastewater to ensure compliance with the NOMs. Article 137 of the Water Regulation requires that all those responsible for discharging wastewater into receiving bodies:

1. Obtain a discharge permit from CNA;
2. Treat all wastewater so that the conditions set forth in the NOMs and the permit are complied with;
3. Pay fees for discharging wastewater into receiving bodies;
4. Install and keep the monitoring equipment in good working condition;
5. Inform CNA of any process changes that entail changes in the volume or characteristics of wastewater discharges;
6. Notify CNA of all pollutants present in wastewater discharges that were not originally considered in the permit application;
7. Operate and keep all the equipment needed for the handling and treatment of wastewater in good working condition to ensure that the quality of wastewater, prior to its discharge, abides by the NOMs and the permit conditions;
8. Cooperate with CNA inspection and enforcement actions;
9. Conduct wastewater quality monitoring and sampling in accordance with the sampling standards provided for in the NOMs;
10. Keep sampling records for at least three years; and
11. Comply with any other regulatory or permit requirements.

Mexico regulates industrial discharges through the issuance of industry specific NOMs such as NOM-001-ECOL-1996.

Urban or Municipal Use

A water use concession must be obtained for all state and municipal exploitation, use or development of national surface or ground water intended for the public aqueduct or sewage systems. Municipalities are responsible for controlling wastewater discharges into drainage or sewage systems within their own jurisdiction. All wastewater discharges into municipal drains and sewers must comply with the LMPs established in NOM-031-ECOL-1993. Whoever engages in such discharges is responsible for ensuring that wastewater is treated and complies with this NOM.

Urban and municipal discharges into national waters must also be permitted by the CNA. Besides complying with the general obligations imposed upon users engaging in discharges, state and municipalities accepting wastewater discharges must:

• keep records of the continuous monitoring and control of wastewater discharges into municipal drains and sewers;
• verify the condition and maintenance of the drainage or sewage systems in order to detect any possible leaks that may affect the quality of nearby groundwater or sources of water supply;
• control the quality of wastewater discharges in order to detect the existence of hazardous wastes or materials that could represent a serious hazard for the environment, third parties or their property due to their corrosive, toxic, explosive, reactive or flammable characteristics.

In accordance with article 126 of the Ecology Law, municipal, state and Federal District authorities that operate wastewater treatment facilities must comply with the applicable NOMs, specifically NOM-003-ECOL-1997.

Public Registry of Water Rights

Articles 30 through 32 of the National Waters Law, as well as articles 54 through 63 of the Water Regulation, provide for a Public Registry of Water Rights (Registro Público de Derechos de Agua), kept by the CNA, which does third parties as an official national record of all water concessions and discharge permits and any extension, suspension, termination or transfer thereof. In addition, all water reserve zones, water extraction works, as well as aquifer and groundwater access points are recorded there. The function of the Public Registry is twofold. On the one hand, it provides a means for proving the existence, ownership, status and notification of titles and the particulars of the legal owners, for transfer purposes. On the other hand, the Public Registry provides a means for CNA to monitor aquifer and ground water quality and development.

Wastewater inventory

In accordance with Article 109 Bis of the Ecology Law and the regulation thereunder, SEMARNAT keeps an inventory of wastewater discharged into federal receiving bodies or leaked into the subsoil, and an information system pertaining to all issued permits, authorizations and licenses. This system is part of the National Environmental and Natural Resources Information System (Sistema Nacional de Información Ambiental y de Recursos Naturales), which is available for public consultation.

9.3 Non-Point Sources

Even though legal provisions apply to both point and non-point sources, the latter are not specifically defined under Mexican legislation. Generally speaking, non-point sources are classified according to the activity that generates them; so they may be industrial, farming or municipal. However, article 130 of the Ecology Law mentions that SEMARNAT, in coordination with the SM, is responsible for authorizing discharges of wastewater originating in non-point sources into marine waters.

9.4 Protection of Safe Drinking Water

Provisions that regulate safe drinking water are set forth under the Public Urban Use Provisions of the National Waters Law (Uso Urbano Público de la Ley de Aguas Nacionales) and the Regulation under the General Health Law (Ley General de Salud). Pursuant to Article 38 of the National Waters Law, CNA may establish reserve zones for the purpose of preserving drinking water sources and protect them from contamination.

Drinking Water Standards

Minimum drinking water standards are set forth in the Regulation under the General Health Law Regarding the Sanitary Control of Activities, Facilities, Products and Services (Reglamento de la Ley General de Salud en Materia de Control Sanitario de Actividades, Establecimientos, Productos y Servicios). CNA, together with SEMARNAT have issued NOM-001-ECOL-1996 and NOM-002-ECOL-1996, that regulate the handling and protection of water supply for human consumption.

9.5 Protection of Groundwater

Provisions Under the Ecology Law

Groundwater protection regulations are embedded in the general use and pollution prevention provisions that apply to all national waters. Under Articles 88 and 89 of the Ecology Law, the preservation of the basic flows of water currents and the capacity of aquifers to replenish themselves must be taken into consideration when establishing national water planning policies and granting or revoking concessions, permits or authorizations for the exploitation of ground waters. On the other hand, SEMARNAT in coordination with the SSA may issue NOMs aimed at the protection of ground waters. Moreover, pursuant to Articles 117 and 122 of the Ecology Law, all contaminated wastewater discharges must be treated in order to avoid the alteration or pollution of ground waters. In addition, the Ecology Law generally provides that all land use must occur in a way that does not alter the ecosystem's balance, thereby implying that land use practices may not contaminate or deplete groundwater supplies.

Provisions Under the National Waters Law and its Regulation

The National Waters Law reasserts and supports the general policies set out in the Ecology Law. National ground waters may be extracted at will, unless expressly restricted by the CNA. Discharge standards and the permitting regime specifically apply to all individual or legal entities that intend to discharge wastewater that may infiltrate soils or contaminate ground waters. In addition, Article 137 of the Water Regulation specifically charges the CNA with taking all "necessary measures and actions" to issue NOMs that are compatible with soil use, in order to prevent groundwater contamination. As part of the National Water Plan (Plan Nacional de Aguas), CNA must prepare a comprehensive groundwater protection program based on the relationship between land use and the quantity and quality of ground waters. As mentioned above, CNA monitors groundwater use and quality through the Public Registry of Water Rights.

9.6 Water Quantity and Use

Articles 88 and 89 of the Ecology Law state that water use must coincide with the protection of aquatic ecosystems and hydraulic cycles. The Law also calls for specific NOMs to be established for the management and protection of all water zones, including rivers, springs, reservoirs and water supply sources for human consumption. Water quantity and use allocation are specifically spelled out under the National Water Plan (Plan Nacional Hidráulico). Based primarily on studies carried out by the CNA Technical Council, the National Hydraulic Plan must specifically include those sustainable development policies that are implemented whenever water quantity is allocated among users through the concession system discussed in greater detail under Section 9.2, "Point Sources". Under the National Waters Law and its Regulation, the CNA is allowed to ration out and allocate water use concessions to municipalities, rural farmland concessionaires or communities, as well as to electrical power generation plants, for exploitation and supply purposes. Pursuant to Article 78 of the Water Regulation, CNA may also create reserve zones for particular water uses. All quantity and use allocations are recorded in the Public Registry of Water Rights.

9.7 Protection of Fresh Water Ecosystems

Policy Provisions

Under Article 89 of the Ecology Law, the protection of the aquatic systems and their ecological balance must be taken into account when taking the following administrative actions:

1. Devising and implementing the National Water Plan;
2. Granting water concessions and wastewater discharge permits, as well as all authorizations pertaining to the use of natural resources that may affect the hydraulic cycle;
3. Issuing authorizations to divert water bodies;
4. Issuing groundwater use restrictions;
5. Stopping those activities that endanger national waters;
6. Operating and managing potable water and drainage systems;
7. Establishing water re-use policies;
8. Protecting aquatic species that are endemic or threatened with extinction;
9. Establishing aquaculture districts; and
10. Creating and administering fisheries protection zones.

Environmental impacts assessments (EIAs) may also be required prior to authorizing fishing activities that may endanger an aquatic ecosystem. On the other hand, in accordance with Article 96 of the Ecology Law, SEMARNAT is empowered to issue NOMs for the protection and remediation of aquatic ecosystems.

Restricted and Water Reserve Zones

Pursuant to Article 38 of the National Waters Law, the creation of restricted water zones in the public interest is the administrative instrument implemented for the protection of aquatic ecosystems for the purpose of: (1) preventing the over-exploitation of an ecosystem; (2) protecting aquatic ecosystems; (3) preserving or controlling water quality; (4) preserving and protecting drinking water supplies; and (5) providing relief in the occurrence of severe water shortages or droughts.

Special Wetland Protection Provisions

Wetlands are broadly defined under the Water Regulation as those transition zones between the aquatic systems and temporary or permanently flooded lands, whether they are tidelands, such as marshes, bogs, swamps or mud flats, whose boundaries are defined by the presence of permanent or seasonal hydrophilic vegetation, or areas where the soil is predominantly humid due to natural aquifer draining. Article 155 of the Water Regulation charges CNA with the following responsibilities pertaining to wetland preservation:

1. Establishing an inventory of national wetlands;
2. Promoting the declaration of those wetlands as national ecological reserves;
3. Issuing special mandatory conditions for the preservation, protection or restoration of wetlands and, more specifically, those of their aquatic and hydrological ecosystems, including their scenic, tourist or recreational value;
4. Promoting and taking those actions which are needed to restore wetlands, including the setting of natural or artificial protection boundaries; and
5. Granting permits to drain wetlands whenever it is deemed necessary for the purpose of protecting public health.

9.8 Liability and Enforcement

General Enforcement Standards

CNA has broad authority to apply sanctions for violations under the National Waters Law, its implementing Regulation, and the NOMs. Article 119 of the National Waters Law spells out a lengthy list of offenses, including:

1. Unlawfully discharging wastewater into federally owned receiving bodies, including sea waters or lands, that may contaminate the subsoil or aquifer;
2. Exploiting or using national wastewater in contravention of the applicable NOMs with respect to the particular conditions set forth for such purpose;
3. Exploiting, using or benefiting from national waters in volumes greater than those authorized in the respective titles registered in the Public Registry of Water Rights;
4. Occupying the national waters or protected zones referenced in Article 113, without being so authorized by the CNA;
5. Altering a water project or hydraulic infrastructure without the consent of the CNA;
6. Failing to implement the infrastructure works or facilities required for water distribution purposes;
7. Failing to install the necessary water quantity and quality monitoring systems, or illegally modifying them;
8. Exploiting, using or benefiting from national waters without holding the appropriate concession;
9. Extracting waters in prohibited, regulated or restricted zones or building facilities to extract those waters;
10. Obstructing CNA inspections;
11. Failing to provide information to CNA for compliance verification purposes;
12. Illegally attempting to dilute wastewater for discharge purposes;
13. Supplying water for human consumption that fails to comply with the applicable quality standards;
14. Dumping or depositing waste, hazardous toxic substances and wastewater treatment sludge into any waters, in violation of the law;
15. Failing to comply with the terms of a concession or permit;
16. Failing to request registration in the Public Registry of Water Rights;
17. Unnecessary water waste; and
18. Any other violation under the law or its regulation.

The application of sanctions under the National Waters Law does not preclude the application of penalties provided for under the Ecology Law, the General Health Law or the Civil and Penal Codes.

Sanctions and Penalties

Sanctions and penalties under the National Waters Law are established in an upward sliding scale depending upon the type and seriousness of the violation, in accordance with Article 119. In assessing penalties, CNA must take into account the seriousness of the offense, the financial circumstances of the offender and whether the latter is a first time offender or a repeat offender. Where administrative orders to remedy violations are issued, additional fines may be imposed for each day the violation continues, provided that those fines do not exceed the maximum penalty allowed in accordance with the upward sliding scale. Repeat offenders are subject to fines up to twice those originally imposed, provided the maximum penalty allowed under the upward sliding scale is not exceeded.

Plant Closure

In addition, CNA may impose the permanent or temporary, total or partial closure of facilities that violate provisions 1, 4, 8, 9, and 12 of Article 119; relapses may be penalized in the same way. CNA may also shut down a facility for failing to comply with a discharge cease and desist order, as well as for unlawfully exploiting or using national waters without being so authorized.

Suspension of Concessions or Discharge Permits

CNA has the ability to temporarily suspend or permanently revoke concessions and permits where the concessionaire or permit holder has violated the terms of the authorization or the provisions of the water law regime. A concession may be temporarily suspended and sanctions imposed whenever the concessionaire: (1) fails to make the payments pertaining to the water supply use rights; (2) does not allow an inspection or the monitoring of water resources or infrastructure to be performed; or (3) fails to comply with the provisions spelled out in the concession. In addition, CNA may prohibit wastewater discharges for: failure to hold a wastewater discharge permit, in accordance with the law, or pay water fees for the use of receiving bodies; exceeding the LMPs established in the NOMs or the special conditions set forth in the permit; or diluting discharge waters, in an unauthorized manner, in order to meet the LMPs or the special permit conditions.

Revocation of Concessions and Discharge Permits

A concession may be permanently revoked or terminated when the concession has expired or the concessionaire has failed to comply with the terms of the concession. CNA must, nevertheless, notify the concessionaire and give him the opportunity to be heard at an administrative hearing, prior to revoking the concession. Upon the revocation being ordered, ownership rights under the concession return to the Nation. CNA may revoke a discharge permit when a permit holder discharges wastewater in a non-authorized location, when discharges originate in a forbidden activity or when the water use concession granted to the permit holder for the exploitation, use or development of wastewater discharges has been revoked. The suspension or revocation of permits does not preclude fines or other administrative, civil or criminal sanctions from being imposed.

Mediation and Arbitration

The Water Regulation establishes a mediation and arbitration system for private disputes over water use issues.

Revision Recourse

The National Waters Law contemplates a Review Appeal against administrative actions or decisions taken by the CNA, whenever these cause harm to private parties.