Mud Pothole in the grassy area

There is a slightly deep pothole on the walking path of the canal on the grass area just by Cafe Mai (come out of Cafe Mai and turn left heading towards Skeeters Axe throwing). I was walking with my 80+ year old dad on the canal the other day and he had to move out of the way due to oncoming crowd walking by. He stepped into the unnoticeable pothole and tripped over - luckily not injured and only with a few scratches. However he could have injured himself more or fallen into the canal.