Your drain field does most of the real work in a septic system, and it is usually the first part to fail on Merritt Island. If you need drain field replacement in Merritt Island, or you are not sure whether a repair will do, this page explains what goes wrong, how to spot it and what a new field involves on an island with a high water table and sandy soil.
What a drain field does
Wastewater leaves your home and settles in the septic tank. The liquid then flows out to the drain field, also called a leach field or drainfield. It is a set of pipes or chambers buried in sand. The water trickles down through the soil, which filters it before it reaches groundwater.
For that filtering to work, the soil under the field must be unsaturated, meaning it has air in it, not water. On Merritt Island, where groundwater sits close to the surface, that space is easy to lose.
Why drain fields fail on Merritt Island
- High groundwater. After heavy rain or during the wet season, groundwater can rise into the drain field. The field floods and cannot accept water.
- Clogging. If the tank is not pumped, solids wash into the field and seal the soil.
- Age. Over many years, a layer of slime called biomat builds up and slows drainage until the field quits.
- Roots. Trees and shrubs near the field send roots into pipes.
- Overloading. More people in the house, leaky toilets or draining a pool or hot tub into the system can drown the field.
- Crushing. Driving or parking on the field can crack pipes and pack the soil.
Signs your drain field is failing
- Wet, spongy ground or standing water over the drain field when it has not rained.
- A sewage smell in the yard.
- Slow drains or gurgling throughout the house.
- Backups that return soon after the tank is pumped.
- Unusually green, lush grass in stripes over the field.
If sewage is surfacing in your yard, keep kids and pets away and call right away. It is a health hazard.
Drain field repair vs. replacement
Sometimes a drain field can be saved. A crushed pipe, a clogged distribution box or a blocked line can often be fixed. A field that is only overloaded may recover if you cut water use and fix leaks.
When the soil itself is sealed or the field sits too close to the water table, repair rarely lasts. Replacement is then the real fix. Your contractor will check the tank, the lines and the soil before recommending either one.
What leach field replacement involves
- Diagnosis. The contractor pumps and inspects the tank and checks the drain field.
- Site evaluation. The soil and the seasonal high water table are measured to set the new field's height.
- Permit. Drain field replacement needs a repair permit from the permitting office for Brevard County.
- New field. The old field is removed or abandoned, and a new one is built, often raised with clean fill on island lots.
- Inspection. The new field is inspected before it is covered.
Should you upgrade instead?
Here is the key question for any Merritt Island home: if you are rebuilding the drain field anyway, should you upgrade the whole system now? An in-ground nitrogen-reducing biofilter is essentially a specially built drain field, so a drain field replacement can be a natural point to meet the July 1, 2030 rule. It may also make you eligible for the county's septic upgrade grant, which must be approved before work starts.
Ask your contractor to price both: a straight drain field replacement and a full nitrogen-reducing upgrade. Compare them after the grant. Our cost guide explains the factors that drive both prices.
Leach field replacement on small island lots
Many Merritt Island lots are narrow, with pools, docks or seawalls taking up yard space. When there is not enough room for a standard field at the right height, the contractor may suggest a different layout, a raised design with sloped edges, or a smaller-footprint system such as an aerobic unit. These choices affect both cost and upkeep, so ask to see the options side by side.
Protect your new drain field
- Pump the tank on a regular schedule.
- Keep cars, sheds, pools and pavers off the field.
- Plant only grass over it, and keep trees well away.
- Point gutters and pool drains away from the field.
- Spread out laundry over the week instead of doing it all in one day.