SOUTHERN CALIFORNIA — Winter is officially underway and Southern California has already experienced cold temperatures and sporadic rain, while local beaches and harbors also experienced King Tides between Dec. 22 and 24. Forecasters predict a wet winter courtesy of El Niño. Will the combination of El Niño and King Tides cause adverse conditions in local waters for boaters and coastal residents?
The King Tide event during the first week of winter does not provide a large enough sample size for what could be in store during the next three to four months. Water levels in Huntington Beach and Newport Beach between Dec. 22 and 24, however, could offer a glimpse of future coastal flooding.
A boat launch ramp on Lido Island in Newport Beach, for example, was almost fully underwater on Dec. 24.
Water levels at the Grand Canal at Newport Beach’s Balboa Island appeared to be higher than previously observed marks. Residential piers in the canal were partially submerged and there was extremely tight clearance under the bridge connecting Little Balboa to Balboa Island.
County workers were monitoring the seawall along Pacific Coast Highway at Huntington Harbour on Dec. 23, as the water was spilling onto the street. The entire length of an alleyway adjacent to the harbor was about 6 inches underwater.
Charlotte Stevenson of USC Sea Grant stated, in an article published by the National Oceanic and Atmospheric Administration (NOAA), King Tides offer a glimpse of coastal flooding resulting from predicted sea level rise.
“King Tides are simply the highest tides of the year, occurring when there is an alignment of the gravitational pull between moon and sun. During these extreme high tide events, Californians get an idea of what future sea level may look like in their coastal communities,” Stevenson wrote. “The sea is already rising. NOAA reports a 0.04-0.1 inch rise in sea level over the last 100 years, and a recent NOAA report on ‘nuisance flooding’ shows increases of 300-900 percent on all three U.S. coastlines since 1960.”
Rising sea levels could result in permanent damage to ports and harbors, loss of beaches and habitat preserves, and flooding of highways and other important infrastructure, according to NOAA.
The National Ocean Service predicted coastal flooding resulting from King Tides in Huntington Beach, Newport Beach, Los Angeles, San Diego and other beach cities could be a regular occurrence this winter season. A combination of King Tides and El Niño might result in nuisance flooding.
“Over Thanksgiving, observed tides at several NOAA tide stations in Southern California were higher than ever measured before, even during storms, which caused minor flooding around San Diego,” a NOAA announcement on coastal flooding stated. “Flooding impacts may become significantly worse if King Tides coincide with a coastal storm.”
A NOAA report published in September 2015 found nuisance flooding could regularly occur at California’s coastal communities throughout the next four months.
“Many mid-Atlantic and West Coast communities could see the highest number of nuisance flooding days on record through April due to higher sea levels and more frequent storm surge, compounded by strengthening El Niño,” NOAA officials stated in response to its September 2015 report. “These communities may experience a 33 to 125 percent increase in the number of nuisance flooding days.”
Coastal flooding and high tides impact launch ramps, piers, and how boaters navigate through local waterways. Heavy rains and flooding also increase the amount of marine debris in local waters.
NOAA predicts one more King Tide event on Jan. 21 and 22