The idea is God created it. So yeah
BTW different translations
Sahih International
He released the two seas, meeting [side by side];
Muhsin Khan
He has let loosed the two seas (the salt water and the sweet) meeting together.
Pickthall
He hath loosed the two seas. They meet.
Yusuf Ali
He has let free the two bodies of flowing water, meeting together:
Shakir
He has made the two seas to flow freely (so that) they meet together:
Dr. Ghali
He merged the two seas (that) meet together;
BTW different translations
Sahih International
He released the two seas, meeting [side by side];
Muhsin Khan
He has let loosed the two seas (the salt water and the sweet) meeting together.
Pickthall
He hath loosed the two seas. They meet.
Yusuf Ali
He has let free the two bodies of flowing water, meeting together:
Shakir
He has made the two seas to flow freely (so that) they meet together:
Dr. Ghali
He merged the two seas (that) meet together;