So, correct me if I am wrong but :- you will need a generator or a rcd supplied power cable running over a wet drive to power your sucker thing that you will have to empty every 4 minutes on a machine that runs @ 15 l/min. The second tank that the other pump fills with recycled water obviously would be used by your jetwash, in my opinion would severely limit the pumps life. I can see this thing being a good idea abeit a totally impractical way of collecting slop, I personally have a bucket with some holes round the top, a small shovel and a hand brush. This piece of equipment may have a home in the most water sensitive enviroment but not on a rainy wet British drive IMO
1 US gal=0.8327 Great British gal
1 gal= approx 4.5 l