LAKE BLUFF, Ill. — A Far North Suburban family say they are going to establish a foundation to honor the memory of their son, who died Sunday from drowning after getting trapped in an Alaskan mud flat.

Twenty-year-old Zachary Porter, of Lake Bluff, Illinois, was walking on tidal mud flats with friends in an Alaskan estuary when he got stuck up to his waist in a quicksand-like silt and drowned as the tide came in before frantic rescuers could pull him out, authorities said.

“He was the best in all of us,” said Elizabeth Porter, Zachary’s sister.

Family told WGN that Porter was a young man known for his compassionate heart and concern for others. He was a mentor to local baseball players and those learning how to sail on Lake Michigan, as well as a student enrolled at Washington University, where he majored in Economics with future goals of using his education to help better the lives of others.

“Our grief is unspeakable,” said Susan Rider, Zachary’s mom. “The world lost an incredible human being on Sunday.”

Standing alongside Porter’s caring heart was his love for the outdoors, which led him to travel to the wilderness of Alaska.

“He wanted to experience and enjoy the outdoor world,” said Todd Porter, Zachary’s dad. “That was a part of his passion.”

The accident was the latest tragedy at Turnagain Arm — the estuary where Porter lost his life. The 48-mile-long estuary was carved out long ago by glaciers that travel southeast from Anchorage, Alaska, and parallels a major highway in the area. At low tide, the estuary is known for its dangerous mud flats made of silt from rocks that were pulverized by glaciers over time.

At least three other people have gotten stuck and drowned at Turnagain Arm over the years, with many more having been rescued, including someone who was fishing in the area as recently as last month.

“It’s big, it’s amazing, it’s beautiful, and it’s overwhelming,” Kristy Peterson, the administrator and lead EMT for the Hope-Sunrise Volunteer Fire Department, said of Alaska. “But you have to remember that it’s Mother Nature, and she has no mercy for humanity.”

Peterson, who responded to the call, spoke with others in Porter’s party but didn’t talk to him during the desperate rescue attempt.

“When we respond, we respond with the utmost of good intentions and as mothers and fathers and uncles and brothers,” she said. “We respond with as much passion and vigor as we can.”

The volunteer members of the department will gather later in the week for a debriefing, she said.

“I have been in contact with all my members, and they’re all heartbroken,” Peterson said. “This is a hard situation.”

While the family said they are not ready to discuss the accident itself, they said they will be starting a foundation to honor Porter’s memory.

“Its mission is going to be to ensure other boys and girls have an opportunity to have the kinds of opportunities he had,” Rider said.