how do you know when a leech field is bad?
Answers:
When your lateral line quit taking water the hole are usually plugged up. If you pull the clean out plug in the septic tank
there will probably be a back pressure making it run out on the ground. Some lateral line can be replaced and new gravel put back into the original trenches. This will let it go back into the ground.
Other answers:
when they are all dead
when they are all dead
Well, it isnt so much the leech field (I am assuming you are talking about a spetic system.) It may be that your tank is full, or has alot of undigested solids in it. They make an enzyme that you can flush down your toilet. If I am not mistaken, its called Rid X or something along that line. This sometimes will eat up any paper or solids in the tank. Sometimes though, they just need to be pumped out.
Also, if you have had alot of rain, it may be that your field is saturated with rain water, giving the sewage no place to drain to.
when septic tank has to be pumped more often than usual.