I am on a septic tank and it was cleaned out about 7 years ago. I have a garbage disposal on my kitchen sink. It has rained recently. I can't understand why I am getting standing water in my dishwasher. Please someone give me some theories on how to avoid the standing water in my dishwasher.

Do you have any other drainage problems. Do you have an airgap for the dishwasher? If you do not have an air gap is the dishwasher drain hose secured up to the bottom of the counter top? Does this only occur when you have rain?

Despite the fact that your septic should be checked every three years or so, (more with a disposal unit) and it's been seven since you checked yours I don't believe that this is a septic tank problem. Now I need some information.
How much water? Does the pump work at all? Is any water entering the disposal when the pump operates? What type of air gap do you have? High loop inder the counter or a counter top air gap? Let me know, tom

Sadly you are talking so far over my head. I have not had any water issues with anything else and the dishwasher acts like it is working but when I open it the detergent is in the bottom hardened kind of and the dishes are hot but no evidence of water. I kept opening and checking during the rinse cycle but never could see water pooling any where. I did see white soapy foam in the back areas but that is about it. Dishes are not clean at all thought

Sounds like you are not getting water to the dish washer as opposed to having a drain problem. A small amount of water stays in the pump to keep the seals wet. That what partially desolved the detergant. Could be a faulty water valve. Time to call a repairman.

Remove water supply to DW. Check if it has water flow. Than check filter at DW water connection. It may be clogged up. Clean it. Standing water inside you DW indicates that you have food leftovers blocking suction. Remove drain cover ( inside, center of DW) and clean it. Now, your DW should work.

Is the garbarator new? Did someone forget to knock out the knock-out? Is the drain piped directly into the continuous waste? Do the sinks drain normally?

Please answer Harolds questions,
Do you have any other drainage problems. Do you have an airgap for the dishwasher? If you do not have an air gap is the dishwasher drain hose secured up to the bottom of the counter top? Does this only occur when you have rain? This problem could occur if the sump were clogged, the discharge hose was kinked, The pump was failing, there was a blockage in the inlet port of the disposal or if there was a partial blockage in the drain line in the wall that backed up into the disposal and back down the DW hose. Lots of things to check here. Good luck, Tom

Tom,
Several old post revived by plumber boi.

Tom,
Several old post revived by plumber boi.
Thanks Harold, I'll handle it. Tom