Campeonato Nacional de Aguas Abiertas Primavera

A body of groundwater fills the hollow of Laguna Esmeralda. This inland water hosts the Campeonato Nacional de Aguas Abiertas Primavera, an open water swimming race held in Laguna Esmeralda in Melipilla, within the central zone of Chile. The venue was established through a formal partnership between the lagoon and the Federación Chilena de Deportes Acuáticos (FECHIDA), creating a designated freshwater home for national open water competition. The championship takes place across an enclosed circuit marked by navigation buoys laid out across the lake. The competition accommodates competitors from age ten upwards across a full slate of distances, offering shorter races of 1,000, 2,000, and 3,000 meters alongside endurance tests of 5,000 and 10,000 meters.

Steering through the buoyed turns requires steady sighting and consistent rhythm on flat water free from ocean swell. Morning hours over the lagoon bring gentle breezes and smooth water ideal for competitive swimming, while afternoon winds pick up considerably across the open surface. Unstable spring weather in the central zone can occasionally trigger storms and low temperatures that require organizers to reschedule dates to protect athletes. When conditions align, the event showcases intense club competition, with powerhouses like Stade Français taking top honours in past editions.

Laguna Esmeralda: groundwater quarry beneath the Coastal Range

Between 1990 and 1992, the Esmeralda sector of Melipilla was heavily excavated to extract aggregate materials for building the Autopista del Sol. As earthmovers dug into the gravel beds, natural groundwater welled up from the underlying aquifer, transforming the extraction pit into an artificial lake. The clean groundwater settled into a serene, landlocked haven tucked just off the regional highway corridor. The industrial past of the quarry is entirely disguised by a surrounding landscape of mountains and trees. The tranquil mountain backdrop frames the water.

Laguna Esmeralda: depth, size and a spring championship

Laguna Esmeralda covers 11 hectares with an average depth of 15 metres of clean water. The groundwater table appeared 2 metres down in the excavation that became Laguna Esmeralda, and the water gradually filled the pit. The lagoon sits at 145 metres above sea level, about 1 km from the town of Melipilla. The lagoon has a nautical school with kayaks, family boats and stand-up paddle boards available for hire. An earlier edition of the spring national open water championship at Laguna Esmeralda was held over two days, on 18 and 19 October, with swimmers from age 10 upwards. Twenty-one clubs took part in that championship, and Stade Français won the points table with 137 points, ahead of Iron Swim with 62 and Club Vita Valdivia with 43.

The Maipo and Puangue river system of Melipilla

Melipilla's geography is threaded with notable watercourses, including the Maipo River, the Puangue River, streams like La Higuera, Cholqui, and Popeta, the Huechún reservoir, and Esmeralda Lagoon itself. The name Puangue originates from pupangue, a traditional term for the aquatic plant Gunnera scabra.

The parkland and swimming beaches of Laguna Esmeralda

Along the shoreline of Laguna Esmeralda, the setting operates as an outdoor park with several beaches scattered around the banks. General swimming is strictly supervised for visitor safety, permitted solely at the main beach whenever an active lifeguard is on duty. The quiet environment around the lagoon makes it a favored gathering ground for birdwatching. Visitors and swimmers resting along the perimeter can watch ducks and diverse aquatic birds navigating the shorelines. The park grounds also shelter an eclectic resident community of deer, horses, llamas, mouflons, peacocks, and geese, turning the post-race lakeside into an engaging rural sanctuary once the competition finishes.