They look sturdy and the wood look thick too and I believe are treated as well so they will last long.
We also heard from others around here about the drip irrigation especially on greenhouses. But it's good to see you did it on open garden. All the best to you as you start anew in your garden.
Since the wood we used is rough-cut lumber it is a true 1-inch thick. When you buy lumber and you purchase a 1x6, the true thickness is 3/4 of an inch and the width is 5 and a half inches, so yes it's nice and sturdy.
We'll see how this new watering system works out, hopefully, without a problem. I just need to remember to turn off the water.