San Elijo Channels Face Challenges 

Sand accumulation is threatening the lagoon’s delicate tidal balance

San Elijo Lagoon is experiencing a significant ecological challenge. Last week, for the fourth time this year, the inlet at Cardiff State Beach closed to San Elijo Lagoon due to an accumulation of sand, threatening the lagoon’s delicate tidal balance and compromising water quality. Recent high tides reopened the inlet and provided a much-needed influx of tidal water to the system. Still, our monitoring data indicates an imminent loss of marine life as the lagoon becomes hypoxic (insufficient oxygen levels) within the coming weeks due to limited tidal flow and rising water temperatures.  

 Above: San Elijo Lagoon channel

In the face of this, Nature Collective’s over 35 year dedication to protecting the lagoon is being tested to the limit. The regular excavation methods have proven inadequate in dealing with the current situation, as continuous monitoring has shown. The San Elijo Lagoon Restoration Project has successfully improved tidal flow, one of its primary objectives. However, this success has given rise to a new challenge: sand is traveling farther into the lagoon channel on the improved tidal flow during winter storms and is blocking the channel, hindering the necessary tidal flow.

Given the urgency and complexity of this situation, an innovative approach is required. Conventional land-based excavation methods are ineffective against the sand buildup in these channel sections. Working with our San Elijo Lagoon Restoration Project partners SANDAG and Caltrans, we have identified that the necessary solution is the transition to aquatic-based dredging. We already have requests for proposals to several qualified operators for this vital operation. Our goal is to remove the sand by the fall, thereby restoring the lagoon’s health. Time is critical in this endeavor, and we are moving as quickly as possible to secure funding and operators to minimize the ecological impacts as much as possible.

Your donation makes urgent monitoring and action like this possible.