CEC Receives Submission on the Deterioration of the Nazas River Lower Basin in the states of Durango and Coahuila, Mexico
Tiohtià:ke (Montreal), 3 September 2025 — Yesterday, Prodefensa del Nazas, A.C., an organization based in Mexico, filed a submission under Chapter 24 of the United States-Mexico-Canada Agreement (USMCA/CUSMA) with the Commission for Environmental Cooperation (CEC). The Submitter asserts that Mexico is failing to effectively enforce its environmental laws to protect the Nazas River, particularly its riverbanks and lower basin in the states of Durango and Coahuila.
In submission SEM-25-001 (Nazas River Lower Basin), the Submitter asserts that the lower basin of the Nazas River has deteriorated at an accelerated pace in recent years due to the construction of water infrastructure projects (dams) which have altered the river’s natural flow. The Submitter asserts that the dams have led to water scarcity, dryness of the riverbed, and a reduction in groundwater recharge. The Submitter also maintains that these dams have impacted local ecosystems, resulting in a loss of forest cover in riparian areas and triggering a state of emergency for the main aquifer in the region (Acuífero Principal Región Lagunera).
The Submitter asserts that by developing and operating dams in the Nazas River Lower Basin, Mexico is failing to effectively enforce its environmental laws to protect, restore and ensure sustainable use of ecosystems and natural resources. The Submitter also asserts that Mexico is failing to meet its obligations to maintain ecological balance and protect the human right to a healthy environment.
The Submitter cites provisions from the National Waters Act (Ley de Aguas Nacionales – LAN), the General Act on Ecological Balance and Environmental Protection (Ley General del Equilibrio Ecológico y la Protección al Ambiente – LGEEPA), and the General Act on Sustainable Forest Development (Ley General del Desarrollo Forestal Sustentable – LGDFS).
The Secretariat will review the submission and determine, within 30 days, whether it meets the requirements of USMCA/CUSMA Articles 24.27(1), (2) and (3). To learn more, please consult the registry page for the submission SEM-25-001 (Nazas River Lower Basin).
Photo: Héctor Esparza
The CEC SEM Process
The CEC Submissions on Enforcement Matters process supports public participation, information-sharing between governments and the public, and transparency and openness in the effective enforcement of environmental law in North America. If you have reason to believe that an environmental law is not being effectively enforced by Canada, Mexico or the United States, the SEM process may address your concerns.
As of 1 July 2020, the CEC’s SEM process is governed by USMCA Articles 24.27 and 24.28 of the Environment Chapter of the free trade agreement between Canada, Mexico and the United States (CUSMA, T-MEC, USMCA).
Want to learn more about the SEM process? Please watch this two-minute video for an introduction: