Septic Systems in Seasonal and Snowbird Homes

A septic system in a home that sits empty part of the year mostly needs planning: fix leaks before you go, keep power and the service contract going if you have an aerobic unit, have someone who can respond to an alarm or a storm, and ease back into heavy water use when you return. Many of the risks are things nobody is there to notice: a running toilet, a tripped breaker, an alarm, or a flooded yard after a storm.

This guide is for owners of seasonal, second and snowbird homes on septic.

How low or on-and-off use affects a septic system

Bacteria in a septic system feed on what goes down the drain. Thurston County Public Health in Washington notes that infrequent use, such as at a vacation home, may not keep enough waste in the system to feed the bacteria. Its advice is to use the toilet a few times when you return, giving the microbes time to rebuild, before doing laundry or other heavy water use.

Aerobic treatment units (ATUs) are more sensitive. Texas A&M AgriLife Extension says the microbes in an ATU need a steady source of organic matter, and that homes with periodic use will have problems keeping a good population of them. Its example: a 2-week vacation lowers the microbial population, and coming home to 10 loads of laundry can flush out what is left. After a period of low activity, it says, the microbes need time to rebuild. An EPA fact sheet on aerobic treatment also lists being "subject to upsets under sudden heavy loads or when neglected" among the drawbacks of these units.

You don't need to add anything to "restart" the system. Thurston County says no additive eliminates the need for routine maintenance and pumping, and the EPA does not recommend septic additives. Our guide to septic tank additives explains why.

Know which system you have

What you need to do while away depends on whether your system uses electricity.

System	Needs power?	What it means while you're away
Conventional gravity system (tank and drain field)	No. UF/IFAS says conventional gravity-fed systems don't rely on electricity.	Little to do beyond fixing leaks and planning pump-outs.
Systems with a pump (such as mound systems)	Yes. UF/IFAS says that when pumps can't run, wastewater keeps collecting in the tank.	A pump alarm needs someone to respond to it.
Aerobic treatment unit (ATU)	Yes, continuously. AgriLife says the aeration system needs a continuous supply of power, because the microbes need the air to survive.	Keep the power on, keep the service contract, and plan for alarms.

If you are not sure what you have, the EPA says your local permitting authority may have a record drawing of the system, or ask the company that last pumped the tank. Our guide to conventional vs. aerobic systems explains the difference.

Before you leave

Fix leaks. The EPA says a single leaky or running toilet can add as much as 200 gallons of water a day. In an empty house, a leak can run for months with no one to hear it, sending that water to the drain field.
Keep power to an ATU. If you switch off breakers when you close up the house, make sure the one feeding an aerobic unit stays on. AgriLife's advice for ATUs is to keep electricity going to the unit. For your unit's own instructions, AgriLife says to follow the manufacturer's recommendations. For other systems with a pump, ask your septic company whether to leave its circuit on while you are away.
Tell your ATU maintenance entity your dates. Florida requires an ATU owner to hold an operating permit, valid for 2 years, and to keep a service contract with a maintenance entity that inspects the unit at least twice a year. (The owner of an owner-occupied single-family home can be approved as the maintenance entity for their own unit after training.) Ask the company how it schedules visits while you are away, how it gets access, and how to reach you.
Arrange for someone to respond to an alarm. AgriLife says that if an ATU alarm sounds, you should call your maintenance provider and cut nonessential water use. An alarm in an empty house only helps if someone hears it. A neighbor or house-watcher with the company's phone number can make that call.
Think about pumping timing. See the section below before you book a pump-out for your last week.
Write down your system details. Keep the tank location, the last pump-out date and the service company's number where you, and anyone checking the house, can find them. The EPA recommends keeping a record of maintenance.

When to schedule pumping

The EPA says household tanks are typically pumped every 3 to 5 years and inspected at least every 3 years, and that systems with pumps, float switches or other mechanical parts should generally be inspected once a year. The Penn State pumping table in our guide on how often to pump a septic tank in Florida is built for homes used all year, so it doesn't fit a part-year home well. Count the months you actually live there, and ask the company to measure the sludge and scum at each visit.

There may also be a reason not to pump right before you leave. A tank refills as the house is used, so a tank pumped in your last week may stay low while the home sits empty. The CDC's flood advice is to have a septic tank at least half full before a flood, to keep it from collapsing or floating. If your empty months fall in the rainy or hurricane season, ask your septic company whether pumping early in your stay makes more sense. And don't have it pumped while the ground is flooded or saturated: Florida DOH and the EPA both warn against it.

National cost guides put a routine pump-out at about $290–$600, and ATU maintenance contracts about $175–$600 a year. See the Florida septic pumping cost guide for details.

Hurricane season while you're away

The Atlantic hurricane season officially runs from June 1 to November 30, according to NOAA's National Hurricane Center. If your Florida home sits empty in the summer and fall, it is empty for the whole season. Plan for that before you leave:

Seal the access points. The CDC suggests sealing the manhole and inspection ports before a flood to keep extra water out of the tank.
Plan for the pump. The CDC and UF/IFAS both say to turn off a septic pump at the circuit box before the area floods. That conflicts with keeping an ATU powered, so ask your maintenance entity what it wants done for your unit if a storm is coming, and who will do it. Whoever does it should not switch a breaker while standing in water: the CDC says never to turn power on or off while standing in water.
Generators. For running a well pump on a generator, UF/IFAS says to have the proper electrical connection installed by a licensed electrician before hurricane season. If you want backup power for a septic pump or ATU, ask an electrician the same question.
Have someone check after the storm. UF/IFAS says not to pump the tank right away while the surrounding soil is still saturated, to inspect the system for damage once floodwaters recede and call a service provider if parts have filled with floodwater, sediment or debris, and to keep vehicles and heavy equipment off the tank and drain field.

Our flood zones and septic systems page shows how to look up your flood zone, and your septic system after a hurricane or flood covers the recovery steps.

When you come back

Start slowly. Use the toilet a few times before running laundry or other heavy water loads (Thurston County).
Spread out laundry. The EPA suggests spreading washing machine use over the week instead of doing it all at once. AgriLife's example of 10 loads on the first day is the one to avoid.
Check the alarm panel if you have a pump or an ATU, and call the maintenance company if it is showing an alarm.
Walk the yard. Look for wet spots, odors or sinking ground over the tank and drain field. Our list of septic warning signs explains what each one may mean.
Pace the guests. Thurston County notes that extended holiday visits strain a system, and suggests reducing water use during those periods.

Frequently asked questions

Should I pump my septic tank before I leave for the season?

Not automatically. Pump when the tank is due, based on sludge and scum measurements. A tank pumped just before you leave may stay low while the home is empty, and the CDC's flood advice is to have a tank at least half full before a flood. Ask your septic company what fits your schedule.

Can I turn off my aerobic unit while I'm away?

AgriLife Extension says an ATU needs a continuous supply of power for its aeration system. Follow the manufacturer's instructions and ask your maintenance entity before you switch anything off.

Will the bacteria die while the house is empty?

Their numbers can drop. Thurston County and AgriLife both say the microbes need time to rebuild after low use, so ease back into heavy water use. Additives are not needed.

Does my ATU still need its inspections if I'm only here in winter?

Florida law says the maintenance entity inspects each ATU at least twice a year, and requires the owner to keep a current maintenance service agreement. Ask your maintenance entity how it schedules visits for a seasonal home.

Who can check my system while I'm gone?

A septic company can inspect or pump it, and an ATU maintenance entity handles the unit itself. Browse the directory or start with Ocala, Clermont, Leesburg, Zephyrhills and Wesley Chapel.