re: water levels

[mamoose]

Can an excessive amounts of melting snow and rain cause septic system to be filled with water and create slow moving drains? The soil is primarily clay and saturated with water.
Toilet and shower drain properly for a couple of days, then drain ever so slowly for several days, then flow again normally. (Shower flows into same drain as toilet - sewer pipe to septic system no more than 25')
Kitchen and bathroom sink drain normally.
Basement sink (waste water pumped to sewer pipe) seems unaffected.

[leejosepho]

Can an excessive amounts of melting snow and rain cause septic system to be filled with water and create slow moving drains?

Certainly, when the soil is saturated and the tank's output has nowhere to go.

Toilet and shower ... drain ever so slowly for several days ...
Kitchen and bathroom sink drain normally.
Basement sink (waste water pumped to sewer pipe) seems unaffected.

The ejector pump in the basement has the ability to actually force water out of the house, and the bathroom sink puts out far less than the toilet or tub. The kitchen sink probably puts out a little more than the toilet, but I would guess it has more "drain room" (piping) serving as a buffer between it and the septic tank.

You problem will likely go away as the ground dries up a bit, but this might be a good time to have your septic tank cleaned and pumped anyway while also lightening the load on your drain field for a couple of days.

[hj]

In fact, since the field is open to the ground for water to escape, if the ground is completely saturated, that water can flow INTO the pipes and flood the tank AND your drain lines in the building.