Even though they stock between 3000 and 5000 one year old trout every year, the vast majority don't survive a year. They are probably eaten by other larger fish.
This one and another I caught were measured at 3 pounds. I just lifted up the net with scale then deducted the net weight. It would be 20-22 inches.
There is a survey you should take and let MNR know that you want trophy fishing lakes or any other improvement.