We have been making a new raised bed on the lawn for soft fruit bushes. The lawn been there for many decades so is very compacted. During the heavy rain earlier the year the area flooded and we did not want fruit bushes sitting in water.
The first stage was to remove the turf followed by a gentle forking over of the soil. I know we are no-dig gardeners but looking at the soil under the grass convinced us it needed loosening.
The videos below show a simple drainage test. The first is on the compacted soil just after the turf was removed. The water puddles and takes a few seconds to drain away. The second video shows the improved drainage after forking, the water disappears almost immediately the flow is stopped.