When the it first came out I was using a 3" hydroforce on dry land. I had a creekbed I was working to try to get down to bedrock. I modified the set up where I had a P180 running the nozzle, but about 6 feet upstream of the nozzle I had a "helper jet" which was an inline power jet which was run by another P180 then the suction hose went to a sluice box. With that set up, I literally dug a 10 foot deep hole on dry land with the hydroforce. The cool thing about the hydroforce, is you are always working about a 6" deep pool of water- as long as you keep the pool 6" deep, it doesn't spray back in your face, and you can keep going down. I never got down to the bottom of the creek at 10 feet as the bedrock kept angling down and winter set in and so I was done for the season.