If you went to school in San Diego while you were in fourth grade, you probably studied the California Missions chain and, in particular, the San Diego de Alcalá Mission. The mission is the birthplace of California and its Spanish roots, and it is the link to the past. But there is a hidden part of the mission that played an important role in establishing the mission’s settlement: the Old Mission Dam.
The foundation of the old mission dam
The mission was founded in 1769 by Father Junipero Serra and its original settlement was in the place now known as Presidio Park, just above the old town. But five years later, the mission moved to its current location in Mission Valley, in part to have better access to reliable water (the San Diego River was actually a useful river back then).
The friars explored a location about six miles upstream as an ideal place to build a dam and basin, but construction did not begin until 1809. Indian labor from the mission population was used to build the dam and the channel and was one of the most ambitious in the California mission chain.
Construction of the old mission dam
The dam was built over the head of Mission Gorge, and the 244-foot-long, 13-foot-thick, and 13-foot-wide dam was built of stone and cement into exposed bedrock, creating a permanent reservoir behind it. The water was released through gates and spillways into a six-mile-long, gravity-fed, tile-lined channel through the gorge and Mission Valley, ending in a sedimentation basin near the Mission. Construction was completed in 1815 and the parents had the water they needed.
The usefulness of the dam for the mission would not last long: the missions were secularized in 1833 and by 1867, the dam was in poor condition and mostly in ruins. The remains of the dam are still in place, but the canal system is long gone.
Visiting the old mission dam
Today, you can still visit the Old Mission Dam as part of Mission Trails Regional Park. In fact, there is still a pool of water retained by the now historic structure.
The Old Mission Dam is a nationally registered historic landmark and starting point for hiking in Oak Canyon, the East Fortuna Mountain region, or along the Father Junipero Serra Trail and the San Diego River. This is a great area for bird watching and just relaxing. The path to the San Diego River is wheelchair accessible.
You can visit from 8:00 am to 5:00 pm from November 1 to March 31, and from 8:00 am to 7:00 pm from April 1 to October 31. The entrance to Old Mission Dam is located on One Father Junipero Serra Trail in San Diego
