Much of economic activity requires the discharge of wastewater. While in some cases it is possible to discharge it into sewer systems, in others, wastewater must be discharged into rivers, lakes or directly into the subsoil, either because there is no sewer infrastructure or because the authorities operating the sewers do not allow it.
Unfortunately, poor management of wastewater discharges has caused some rivers and lakes to show high levels of pollution. As an example, in 2021, the National Water Commission (CONAGUA) monitored 788 rivers and lakes across the country, and around 300 reported some kind of pollution.
Water pollution is a worrying factor for everyone, as it generates various environmental and social conflicts. For this reason, CONAGUA has ordered the definitive closure of some projects and has imposed sanctions and the obligation to remedy those who generate the discharges.
Considering the above, we recommend that those who discharge wastewater into rivers, lakes and subsoil consider the following points to ensure that their discharge is legal:
- Have a discharge permit issued by CONAGUA. Anyone intending to discharge wastewater into rivers, lakes or underground must first obtain this permit. In this sense, watering green areas with wastewater is considered a discharge into the underground. Discharging without this permit could result in fines and the closure of the activities that caused the discharge.
- Avoid polluting discharges. It is necessary to have a water treatment plant in optimal conditions so that the wastewater to be discharged complies with the parameters established in NOM-001-SEMARNAT-1996. It is important to note that in March 2023, NOM-001-SEMARNAT-2021 will come into force, which establishes stricter quality parameters.
- Submit declarations in the DECLARAGUA system and, where applicable, pay fees. Holders of a discharge permit must inform CONAGUA of the quality and quantity of the wastewater discharged, as well as pay the corresponding fees. If the holder proves that the substances in the discharges are within the maximum permissible limits established in the official Mexican standard, he will be exempt from this payment obligation. To do so, he must present a quality analysis of the wastewater.
- Ensure that the laboratory that issues the analyses is authorized by CONAGUA and accredited by the Mexican Accreditation Entity. If the laboratory does not have current accreditation and/or authorization, its analyses will be invalid and exemption from payment of fees cannot be requested.
- Do not exceed the permitted discharge volume. Discharging more water than authorized, even if it is not contaminated, could lead to the imposition of sanctions.
- Request a discharge permit based on projections and estimates of the wastewater to be discharged. In the event of discrepancies in the declarations, CONAGUA may require payment of fees for the entire permitted volume (regardless of whether a smaller volume was actually discharged).
- Avoid diluting wastewater discharges. This is considered a serious violation that may result in the closure of the project. In addition, CONAGUA may require payment of fees for the total volume established in the permit.
- Request an extension of the permit at least 6 months before its validity expires. Unlike other permits that allow you to request an extension at any time prior to their expiration, permit extensions must be requested at least 6 months before the end of their validity.
- Obtain a concession title to use the riparian areas of rivers or lakes. The river or lake shore is considered a federal zone under CONAGUA's jurisdiction. If the holder of a discharge permit intends to build discharge facilities (such as ramps or pipelines) in this area, he or she must obtain a concession title from CONAGUA.
The care of rivers, lakes and groundwater is of utmost importance to ensure ecological balance. In addition, this will preserve the water supply for human consumption and economic activities. In short, wastewater discharges into these ecosystems must be done very responsibly and in full compliance with environmental regulations.
