Cutler-Orosi School District has confirmed that he was a junior at Orosi High School school.
The heartbreaking news of his death comes just weeks after the district lost a 6th grader, Adrian, who was hit-and-killed while riding an ATV.
"If the public can keep the Culter-Orosi community in their thoughts, in their prayers this continues to be a very tragic year with this back to back tragedy," said Cutler-Orosi Unified Superintendent Yolanda Valdez.
Valdez says the district is providing counseling support to students currently in summer school.
"Immediately students started sharing their thoughts, their feelings on social media. The young man was very much loved and had a big circle of friends," said Valdez.
Alejandro drowned Sunday afternoon while out on a pontoon boat at Shaver Lake with a friend and their family.
The Fresno County Sheriff's Office says while he was wearing a life jacket, it wasn't properly secured.
"The trouble was he had it secured around his neck but he did not cinch it together with the clips around his body. So once he hit the water the jacket popped off and he went under the water," said Tony Botti with the Fresno County Sheriff's Office.
Botti says not only did Alejandro have little to no swim experience, but those with on board with him were not strong swimmers.
Deputies patrolling the water responded, but it would take more than an hour and help from the dive team to locate the teen's body.
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That was the second drowning FCSO responded to in just a matter of days.
On Friday, Ricardo Perez Diaz drowned at Skagg's Bridge Park in Kerman. Botti says the 24-year-old also did not know how to swim.
Authorities are now urging anyone who can't swim to stay out of the water and reminding residents that everyone should wear properly fitted US Coast Guard approved life jackets.
"Especially if you've got kids, make sure you can buckle it well, make sure that it's not up here around their ears. It should fit snuggly, probably even a little bit too tight it is going to loosen a little bit when you get in the water," said Botti.
Fresno County Fire responded to four different rescues over the weekend.
The agency is urging people to take precautions because if they are called, it can take significant time for them to get there, and locate the person in distress.
"So the response times for us were about 15 to 20 minutes to get to the Kings River. Fortunately the Fresno Sheriff's Office was already on the river," said Gary Couch with the Fresno County Fire Department.
"That makes our box of where the victim may have gone in very big."
Couch encourages people to take extra precautions in rivers where currents change day to day.
As for the emotional toll of Alejandro's loss, the school district says there is also assistance available to students and families who are not enrolled in summer courses.
If you would like to help Alejandro's family lay him to rest, you can donate to his mother on Venmo @Claudia-Leon-13.
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