New South Lake Park opens to public in San Marcos

Fishing and hiking are highlights of the new open space

Long-awaited public access to a retired reservoir in San Marcos became a reality today as city and water district officials celebrated the grand opening of South Lake Park.  

The 10-acre site is located at 975 Sunstone Drive and includes a mile-long hiking trail around the lake, idyllic spots for fishing, and a small parking lot.   

“After years of planning, we are so proud to finally cut the ribbon on this much-anticipated community park and welcome residents to this special location,” said City of San Marcos Mayor Rebecca Jones. “Today is a shining example of what is possible when you persevere and hold true to your vision.”  

The park has been planned since 2005, when the city made a deal to rent the old reservoir from Vallecitos Water District for $1 a year for 50 years.  

“When the District’s need for the reservoir ended, the visionary leaders on the City Council and Water Board had the wonderful idea to open this space up to the public,” explained Vallecitos Water District President Jim Hernandez. “Thanks to them, and all those that came after, we can now enjoy this beautiful retreat in our community.”    

The lake was built in 1959 and provided drinking water to the Lake San Marcos and Coronado Hills areas until 1984 when Vallecitos Water District decommissioned its use.  

At its maximum capacity, Southlake can hold 73 million gallons of water. It is filled with run off from rain and fluctuates with drought conditions. The deepest part of the lake is 50 feet.  

Prior to the park opening, the lake was inaccessible to the public and sat behind locked gates. It has served as an emergency water storage reservoir in the past – a role that will continue.   

The project is a joint effort between the City of San Marcos and Vallecitos Water District.  

For more information, please contact the City’s Parks and Recreation Department at or at 760-744-9000.