Telmex has completed and activated a 383-kilometer submarine fiber optic cable connecting San José del Cabo to Mazatlán, Sinaloa. The TMX-5 cable, which crosses the Gulf of California, represents an investment of more than $25 million and is designed to keep Baja California Sur connected when hurricanes knock out land-based networks.
The project, announced on September 23 by Telmex CEO Héctor Slim, links Telmex stations in San José del Cabo and Mazatlán. It creates a redundant communications route for voice, data, and video traffic. Before the cable, the entire peninsula depended on terrestrial fiber lines running north through the desert, a system repeatedly disrupted by tropical storms.
Capacity Built for Decades of Growth
Telmex said the TMX-5 cable can transmit the equivalent of 12 million movies simultaneously. The company designed the infrastructure to meet demand in the Los Cabos region for at least 20 to 25 years. The cable includes 11 pairs of fiber optic strands, totaling 22 individual fibers.
The project received environmental approval from Mexico’s Ministry of Environment and Natural Resources (SEMARNAT) in June 2024. Installation involved coordination with SEMAR (Mexico’s Navy) and the Baja California Sur state government to protect marine ecosystems in the Gulf of California.
Storm Resilience Was the Driving Factor
Los Cabos municipal officials had been working with Telmex for months to advance the project. Municipal Secretary General Alberto Rentería Santana framed it as part of a broader push to make Los Cabos more resilient and economically competitive. Mayor Christian Agúndez Gómez pledged full cooperation during the planning phase.
Residents and business owners in Los Cabos have long dealt with internet and phone outages during hurricane season. When Hurricane Odile struck in 2014, communications were down for days. Tropical storms regularly damage the terrestrial lines that run through remote stretches of the peninsula. The submarine cable now provides an alternate path that bypasses those vulnerable land routes entirely.
Largest Fiber Network in Mexico
Carlos Slim Seade, Telmex’s director general, said on social media that Telmex operates the largest national fiber optic network in the country. The TMX-5 cable closes a new protection ring for the region and opens direct connectivity routes for regional, national, and international traffic.
For the roughly 350,000 residents of Los Cabos, plus thousands of seasonal visitors and remote workers, the cable represents a concrete upgrade in communications reliability. The project was first reported by the Los Cabos municipal government and La Jornada.