Officials were mindful of what happened last Fourth of July weekend when the so-called king tides led to "serious flooding" in beach parking lots and some residential neighborhoods, city spokesman John Pope said.
Fallon James remembers last July 4 in the Balboa Peninsula. She woke up to her neighborhood completely flooded.
"Cars were just driving like through water, basically. It was like unreal," she said.
Another local resident said the water went everywhere.
"Last year, when they forgot to put up the berms it flooded everything - all the streets, all the restaurants, flooded the houses," Ivy Stein said.
This week, the city of Newport Beach isn't taking any chances.
"Last year we got surprised by the high surf. It was significantly higher than what was forecasted, so we're making sure we're above and beyond that this time around," said Micah Martin with Newport Beach Public Works.
Crews were on standby in case more sand needs to be packed, and lifeguards were vigilant of swimmers and asked they use caution.
The high tides are one factor, but Pope said officials were also concerned about "unusual wave action."
"You can get predictions on tides, but you can't always on wave action and how it will behave," he said.
The berms are 14 feet on average and last year they were 10 to 12 feet high. Also, this year the city has built a second berm as an extra line of defense.
The berms are "running for significant parts of the peninsula, but our focus is on Balboa Pier, which tends to be the most vulnerable," Pope said. "We built it up quite a bit on the west side and we're now focusing on the east side and filling in that area."
The king tides brought out lots of people to the Balboa Pier to check out the big waves Wednesday evening.
"This is just a magic evening for all of us that live here and work here. Mother Nature at its best," said Judith Connolly said.
The waves peaked around 8:40 p.m., but there was no flooding Wednesday.
The California Coastal Commission says the king tides will return in early December.
City News Service contributed to this report.