Neighbors say not enough is being done.
Despite parking restrictions nearby, many people use the area near Oro Vista Avenue as a place to swim, relax and even set up camping tents.
"I'm frustrated. This has been going on for two years now," said Jeremy Jover of Riverwood Ranch.
Jover said people double and triple park, blocking the road used to access their community, which is especially important for emergencies.
"We feel victimized and trapped. If we had a fire or a medical emergency there'd be no getting in or out," Jover added.
And those who use the off-limits oasis also leave a lot of trash.
"Feces, urine, public bathing, nudity, drugs, alcohol...it's just a free for all," Jover said.
According to one resident, there were close to 1,500 people gathered at the Tujunga Wash on the Fourth of July last year. Another major concern and Independence Day tradition he's worried about is barbequing.
"They barbecue and it's scary. We're in a fire zone and just one spark and everything goes," said Taras Prodaniuk of Riverwood Ranch.
Los Angeles City Councilwoman Monica Rodriguez's office provided a statement that said:
"My office continues to work to resolve concerns surrounding the recreational use of Tujunga Wash, which is challenging to regulate due to combinations of private and public land ownership. We continue to seek everyone's cooperation and encourage families to seek relief from the heat by taking advantage of the other safe recreational options in the immediate area including the Hansen Dam Aquatic Center."