Conventional Septic Systems: Simple, Durable and Low Maintenance

How a Conventional System Works

All wastewater from the house flows into a buried tank. Solids settle to the bottom, grease rises to the top, and bacteria break down the waste. The liquid in the middle flows to a drainfield, a set of trenches with pipe or chambers in gravel or soil, where it soaks into the ground and the soil completes the treatment.

There is no air pump, chlorinator or control panel, and gravity does the work. On some lots the field sits uphill from the tank and a small pump doses it, an approach known as low-pressure dosing. That adds a pump and an alarm while keeping the rest of the system just as simple.

When a Conventional System Is an Option

A conventional field requires enough suitable soil between the bottom of the trench and rock or groundwater. Toward New Braunfels and the deeper soils east of the lake, and on some acreage around Blanco and Bulverde, the site evaluation often allows it. Closer to Canyon Lake, on thin soil over limestone, it usually does not, and the design calls for an aerobic system.

The soil test determines which system the lot can support. We can put you in touch with an engineer we trust for the site evaluation and design, which gives you that answer early. If you are comparing properties, it helps to know what each one is likely to need. See aerobic vs. conventional for a full comparison.

What We Handle on a Conventional Installation

• Site evaluation and system design by an engineer we refer you to
• Stake out the tank and field from the approved design
• Excavate the tank hole and drainfield trenches to the specified depth and grade
• Set the tank level and connect the line from the house
• Install the pipe or chambers and the fill material the design specifies
• Meet the county inspector before anything is covered
• Backfill, grade and clean up

Caring for Your System

Conventional systems are durable, but they still need reasonable care. Have the tank pumped every few years by a licensed pumping company, depending on household size. Keep vehicles off the drainfield, and direct gutters and downspouts away from it. Avoid grease, wipes and heavy use of a garbage disposal.