Building raised bed over lawn

I am trying to build a garden bed over existing lawn.  I am planning to remove the lawn grass prior to starting the lawn. A question for the group here, there's an existing sprinkler system.

So the area I am planning to build has 3 sprinklers (under the same Zone).  If i just turn off the zone, a portion of that zone will die.  Any ideas on what I can do? is there a good way to figure out the exactly determine an area covered by 1 of the sprinklers?

Thank you so much!

Can you just turn the sprinklers on and see where they spray? Will that show you what area, approximately, they cover?

Also, side note... You don't have to turn over the soil and expose a bunch of weed seeds and disrupt the microbiology in your topsoil. You can simply add compost to the top of the area where you want to grow (over cardboard if there are a lot of weeds), and then plant directly into it without all the extra work and hassle. It also will limit the number of weeds you will have in the area, providing you plenty of spare time to enjoy your garden. ;-)

Instead of removing the grass, I would flip the sod over and plant into that then mulch. If you are doing a large bed perhaps renting a sod cutter would be worthwhile. This way you get the grass to decompose and allow the garden and mulch to smother the bit of grass that tries to come up.

I have just made a similar bed, I dug the sod around my intended bed then flipped it over and mounded it up. The area i dug will be my path