The warmer than normal December followed by a colder than average January is at issue here. The combination melted what little snow we had that was insulating the ground then the cold had enough punch to push frost levels down to shallow pipes. Most of the pipes in question are only 3 feet below the surface. Last year, the issue was such a prolonged cold snap, that the frost was 8 feet deep and capable of freezing city pipes. Many residents ran a pencil-thin stream of water for weeks on end to help keep pipes from freezing. This year, the freeze threat is confronting year round rural residents and weekenders as well.
The last time the lakes area had a rash of frozen septic systems came in other snow-drought years during 2003 and 2005. This year, local residents should be running warm and hot water more frequently. Some options include running the dishwasher more, taking longer hot showers or at least using warm water for clothes washing. The warm December followed by rain and a cold January was about the worst thing that could happen in terms of septic systems; and it came after it appeared a normal snow depth for winter was on target, meaning that some people who may have put down insulating straw or septic blankets may not have done so.