Rich residents in ritzy coastal towns resort to petty tactics in vicious 'sand wars' amid fears one sunny state could lose up to 75% of its beaches

Wealthy California waterfront homeowners are battling it out with each other and the public as the sandy shores in front of their mansions shrink.

The U.S. Geological Survey estimates that up the 75 percent of the Golden State's pristine beaches could become completely eroded by 2100.

As the sands start to disappear, wealthy residents who own the multi-million dollar mansions that line the coast have started to resort to extreme measures to keep the sand for themselves.

Business man James Kohlberg filed a lawsuit against his neighbor and owner of the Milwaukee Brewers Mark Attanasio alleging he has been digging up sand from Broad Beach and taking it back to his house for a construction project.

'This case is about a private property owner using a public beach as their own personal sandbox and the disturbing conversion of a public natural resource (i.e., sand from Broad Beach) for a nearby homeowner's personal, private use,' a copy of the lawsuit obtained by the Los Angeles Times said.

Kohlberg's attorneys claim Attanasio's construction team, JILK Heavy Construction, used excavators in tidal zones - leaking oils and exposing local marine life to potentially hazardous byproducts - and restricted public access to the beach.

Attanasio's attorney said his client's company, 2XMD Partners LLC, has been in compliance with its permits.

'2XMD is in the midst of a fully-permitted emergency repair of the property to protect it from ocean forces. It has secured all permits necessary for the repairs from the City of Malibu and LA County as well as thoroughly vetted all contractors and sub-contractors involved in the project,' his attorney said.

Attanasio bought his Broad Beach home for $23 million in 2007, then purchased a neighboring empty lot a for $6.6 million a decade later, according to the Times.

The Brewers owner got permits to repair a damaged section of seawall in March. Then in June and July, excavators allegedly began dragging sand from the beach onto his private property, the lawsuit claims.

In August, coastal elites were caught putting up what appear to be 'fake' private property signs on public beaches near their waterfront mansions.

A TikToker showed one sign he came across while walking along Lechuza Beach, a thin strip of sand that is open to the public via three access points.

The signs shown in his video read in all caps: 'PRIVATE PROPERTY' and 'THIS BEACH AREA IS ON PRIVATE LOTS. TRESPASSERS WILL BE PROSECUTED.'

As he panned around the beach, the man behind the camera said of the sign: 'This is free land, anybody can be here. ...This is a scam. A Karen scam.'

The video then cuts to the middle of a confrontation between him and an unknown older man holding a bottle of Bud Light, who tried to knock the phone from his hand.

'You just attacked me by grabbing my phone,' the TikToker said.

The older man objected to being recorded without his permission, to which the TikToker reminded him they were on public property.

'You're not on public property,' the older man said.

But according to the California Coastal Act, all beaches are open to the public up to the mean high tide line. This is generally interpreted as wherever the sand gets wet.

In the TikTok video, it appears that the 'no trespassing' sign is placed firmly in wet sand, in other words, well past the high-tide line California law says is deemed public.

The sign even says, 'PUBLIC ACCESS ALONG MEAN HIGH TIDE LINE.'

It's unclear who put up the private property sign, though it calls the property being protected 'Malibu Encinal Homeowner Beach Lots.'

One woman from Laguna Beach was caught on camera screaming at a family with small children to 'get outta here! now!' while she tried to rope off a public beach outside her $6 million property.

The video starts with the homeowner shouting 'there goes the fence!' as she bundles out of her home equipped with a spool of white string.

She throws the spool toward the sand, shouting at the tourists to leave.

'I can say whatever I want to, so get f***ing moving,' she screams.

'I'm not joking around. It's not harassment on the beach, it's harassment in my home property.'

'This is not an Instagram moment-place,' she adds while sectioning off her part of the beach.

'You're in my property, get moving now. Now you're in my property line. Move it.'

'Ma'am, we're f***ing walking,' one woman can be heard retorting, as the homeowner replies: 'Pretty f***ing slow'

The rhetoric escalates as the tourist hits back, saying: 'Jesus Christ... shut the f*** up!' before branding her 'Karen of the week.'

The California Coastal Commission, a state agency that oversees more than 1,000 miles of coastline, found the 'Karen of the week' violated the California Costal Act.