As large waves descended on Oahu’s North Shore this weekend, some big-wave riders took to the water while bystanders watched in awe of nature’s power, wondering what this winter’s surf season will bring.

On Saturday some residents at beachfront properties sat in their backyards looking out at massive waves that will increase in power over the coming weeks.

Along some properties, waves crashing into the sand underneath exposed the black fabric of protective “burritos” — long, sand-filled illegal tubes covered by heavy fabric that create a hard barrier against ocean waves.

Burrito barriers are supposed to be forbidden under state law because they exacerbate shoreline erosion by forcing adjacent sand to wash out to sea.

At the same time, the state Department of Land and Natural Resources has deemed many North Shore homes to be “imminently threatened” and has allowed some homeowners to install burrito barriers on a temporary basis with the condition they be removed in three years.

Oahu has lost as much as one-quarter of its beaches to shoreline hardening over the past century, and scientists warn that figure could rise to 40% by 2050.

Francis Guerrero, 85, lives on a beachside property near Sunset Point that his family has owned since 1948.

On Saturday he was rearranging sand around the property to keep it safe from erosion. But for him, far from causing damage, he said that the swells this weekend had actually brought in more sand around his property and a next-door neighbor’s house, helping stabilize both properties.

“It’s perfect, that’s what we need,” he said.

Guerrero describes himself as a “Kalihi boy” and said that his family moved to the North Shore to “get away from the busy life, because we never ever stopped.”

Through the decades he’s seen a lot at his North Shore home. His house once even fell onto the beach and needed to be moved back onto the land. It now sits several feet from the sand.

Since then, he and his family have planted native plants in his backyard and in the sand in hopes of protecting his home and the shoreline, a strategy that he said has worked so far.

David Kellogg, a hanai relative of Guerrero’s, helped him shovel Saturday.

Kellogg said that January and February will provide the real test of this winter’s impact on North Shore homes.

A high-surf advisory remains in effect until 6 p.m. today. Lifeguards were busy as the weekend kicked off after Thanksgiving, with Honolulu Ocean Safety making 19 rescues on the North Shore on Friday.

“The majority of the rescues involved surfers who needed help out of the large surf at Waimea Bay,” said spokesperson Shayne Enright. “Lifeguards also made roughly 3,400 preventative actions, ensuring people didn’t get into trouble, across North Shore beaches and shorelines.”

On Saturday, just a handful of surfers bold enough to venture into the swirling waters made their way out, passing under yellow warning tape posted across nearly every beach along the North Shore.

Lifeguards only can warn inexperienced surfers from venturing into dangerous North Shore surf and then can only monitor them through binoculars for possible rescue while bystanders watch from safety.

According to a forecast by the National Oceanic and Atmospheric Administration posted online Saturday, high surf is expected to “gradually lower through the weekend as a significant northwest swell moves through” and that “heights should dip below the advisory levels by Monday.”

The forecast said that a “slight increase is possible by midweek” as a small northwest swell arrives, but that surf along south- and east-facing shores is expected to remain small.