1980 flooding of racetrack

A series of living levees — earthen embankments — along the San Dieguito River could help protect affordable housing at the fairgrounds and homes in Del Mar's North Beach.

As part of its sea rise planning, Del Mar has completed a preliminary conceptual plan for three living levees; structures that slope gently to combine flood protection with habitat restoration.  

Sea rise and more frequent storms are expected to worsen river flooding. The northern third of the city is less than 20 feet above sea level. In February 1980, a major flood left the racetrack and fairground, which is lower than the river's south bank, swamped by three to five feet of water.

The levees will reduce, but not eliminate flood risk. Areas that experience flooding will continue to see some flooding similar to existing conditions, a report says. According to the city's adaptation plan, there are over 600 homes in the North Beach area.

Flood map

Imperial Beach is the only city in San Diego with a living levee project, which is along the Bayshore Bikeway through the Tijuana River Valley.

"Del Mar's is a little different," said principal planner Amanda Lee at Monday's city council meeting. It puts several small levees together into a system, she explained.

The first, at the Fairgrounds, will provide flood protection during existing sea level rise and a 10- or 25-year storm flood; one foot of sea level rise and a 10-year storm flood; and 2.5 feet of sea level rise and an annual storm. Levee two — the NC Zone/Public Works — will provide protection during existing sea level rise and 100-year storm flood; and three feet of sea level rise and a 25-year storm flood event.

The third levee at North Beach (north from 15th Street to the San Dieguito river mouth) will provide protection for homes in the 100-year flood zone, but not for beachfront properties subject to ocean flooding.

Any levee project along the river will require coordination and participation from the 22nd District Agricultural Association, including state funding.

City officials said no trails would be removed for the project. The total cost is estimated between 5 and 10 million dollars. The next step is finding funding for modeling studies

"This is probably the most important project we're going to be doing," said council member Dave Druker. "We could lose the North Beach area."