If his evaluation is correct, the it means that the ground around the pipes in the drain field will no longer absorb the water from the septic tank. The ground has either been compacted or the pipes have become coated with material which has clogged the porosity and wont let the water drain out.: The grass quit growing over my drain field in West Texas. : It took 3 yrs, but now I have only weeds with deep roots. : I had the tank pumped out, and the service man left a : note saying my field lines are waterlogged. : What does this mean?