Requires the Secretary of State to report to Congress about Mexico’s water deliveries under the 1944 U.S.–Mexico water treaty: an initial report within 180 days of enactment and yearly thereafter. If the Secretary finds Mexico failed to deliver at least 350,000 acre-feet in the prior year, the President must deny Mexico’s non‑treaty water requests and may limit certain U.S. engagement with affected Mexican economic sectors, except narrowly to counter synthetic‑drug flows.

Creates a short-term waiver path: the Secretary can certify every 120 days that any special water deliveries will be used only for specified emergencies and that allowing them is vital to U.S. national interests, which prevents the automatic denial and engagement limits.