Is this the proper way to extend downsprout?

[Nam Trang]

I hired a plumber to extend downsprout from gutter, and these are the pictures he sent. I am concerned with the extension just sitting on top of the lawn like that. The extension on a different rental I have goes into a drain underground.

[JD Martin]

Not really. The water coming out of the end is going to erode the lawn and soil. Cutting the grass around that will be a royal PITA.

I like to bury them approximately 12" deep and terminate them in a lawn box, which is essentially a pipe/bucket that sits underground with some holes in the bottom and/or sides that the water drains out of. Depending on the size of the roof I'll either use a bubbler, which is a little plastic cap that rises when the water comes out and seals shut when it's done, or I'll put it in an actual drain bucket with a removable clean-out grid on top - this type is more useful if there's a lot of trees and debris that gets washed out of the roof and gutters.

PS: If I "hired" someone to do that job and that's what he gave me I wouldn't pay for it. That job could be done by anyone in less than 5 minutes.