I wouldn't worry about roots affecting your leach field if you are planting annuals. If it is perennials, then you might have the roots get into the lines, just as tree roots will, and plug it up. To play it super safe, you could avoid root crops, but the purpose of the leach field is to remove/kill the bacteria and viruses in the sewage before it gets anywhere. If your lines are buried 5-6 feet deep, the microbes should never work upwards that far for a standard septic design--the water should move outwards and downwards, not upwards. It should never get to the surface. If it did, runoff from heavy rains would be putting the bacteria into the waterways and causing the problems a leach field is designed to prevent. Now if you had an evaporative type system, then you would be bringing the water to the surface and may not want an edible garden on top. Plant roots themselves will not transport the nasty microbes to the surface, only the nutrients and water they absorb. The different results of green/dry people have had really do make sense. In drier climates, grass roots will move downwards to seek water and find it in the leach field. When dry, the grass will stay green over the leach field due to the underground water it is getting. In wetter areas, the grass doesn't have to root as deep to usually have good moisture, but the soil over the leach field usually has very good drainage, so during dry periods, the ground will dry out quickly and the grass turn brown.

g'day sue, for me i can't see why not so long as the fruit maybe hasn't been sitting in or on the actual water in the field. there is a whole process that goes on before plants get nutrients and water from such sources (that's why grass & weed growing in these places are so lush and green good nutrient supply) so can't even imagine how any say pathogens would transfer to the flesh of the fruit, even if you thought it was on the skin it could be peeled or washed or both. we also have at least one link to a site that promotes planting over or near leech fields. and if the septic is working as it should there is a whole process that goes on in the tank before that water is expelled to the leech field. my father used to have a hole dug below the leach field and he would bucket that water to the vege' patch, also had neighbours who micro irrigated their cottage garden with the stuff right from the tank used to stink a bit but no one has suffered. reckon i would need to see hard case evidence of anyone anywhere actually getting sick from eating produce grown using this water. always an emotive issue with lots of fear hype attached. i hear the same thing about grey water use in gardens we have always used it and to date we rarely even get the common cold. len Here is a link that might be useful: len's garden page

This I would love a picture of. How much water are we talking about? mmarker, I have a septic tank also. What I would try first is shaving the stump down to ground level (yuck) and applying Round Up to the cut wood. Honestly you only need to spray the live outside parts of the stump but I know I couldn't resist giving it a bath like you're not supposed to. Even with out Round Up eventually the stump/roots will die. No leaves to complete the life cycle. Also, how big a darned dogwood did you have? My best personal stump work was done with a shovel and a sawzall. Over my septic field I'd hate to have any heavier equipment.

Castoff, Sounds like you have systems that are similar to Vermont's. We also have open and closed systems, distribution boxes, etc. The 2 systems with pumps that I described both had leaching areas remote from and higher than the tank and so had to be pumped. In this area if it is all clay soil, I can almost gurantee that a raised leaching area would be required..here they are called "mound systems." In my dealings (until new State laws were passed 3 or 4 yrs ago) each town or city had its own regulations. The smaller towns did nothing. They left it up to home owners and local contractors to design and build their own systems. In most of these cases they were rural communities and the landowners had many acres...the practice was to just build something big enough and to heck with any fancy design. The State of VT now has to issue permits for all designs. The trade off for this regulation is that they will now accept "modern" systems that allow systems in soils that would never work before. When a system is being designed a "perk test:" has to be done on the soil. A hole is dug with a back hoe and the engineer/designer establishes soil conditions at different levels. Then water is poured into the hole and a timing is done to determine how long it takes for the water to leach out. I can tell you that in the civilized areas here, the clay soild conditions that you describe, especially with seasonal high water, would never pass and would require a built up mound system I must confess that I haven't fooled with systems for about 8 years and don't know the specs on the new systems that are allowed or if the new tanks are 2 chambered. I know that many of the designers are requiring filters on the outgoing side of the tank. Possibly this serves the same purpose as the 2 chamber tank. Once a year, you pull the filter out of the inspection hole on the outgoing side and hose it off. I hope that the PO finds some solution. It would be too bad to find out that money had been spent on a design that doesn't work. If it only floods on a seasonal basis, then it does sound like a design problem. If that was the case and it wasn't too terrible, I would investigate anything that might lessen the water flow to the system.....low flow fixtures....toilets, shower heads, etc. I guess I'm trying to think of ways to save someone money, but this system could be beyond that. I don't know what part of Canada the PO is in. I owned property in rural Quebec in a small towwn. I can tell you that there was no regulation (20 yrs ago) over septic systems...at least no regulation that was enforced unless it was a newly constructed building. This town was small enough that the town clerk's office was in the living room of his house and was only open 2 nights per week:-)