Septic tank location sketch How to Find & Use Records to Locate the Septic Drainfield

How to obtain records and revew documents to find the septic tank, drainfield, or soakaway bed. We explain where to go to ask for records that can document the "as approved" as well as the "as built" septic system design. We warn that because of discoveries that may be made during site excavation to install a septic system tank or drainfield, the "as built" results do not always agree with the "as approved" or "as planned" design.

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How to Use Septic System Records to Find the Drainfield - Whom to Ask - How to Find the Septic Leach Fields - Part 3

LARGER IMAGE: this simple sketch of septic tank location can save future trouble.

Finding a hidden, buried septic component: Since the septic system's drainfield is normally a buried system, knowing just where it is located can be tricky.

Since haphazard excavation by hand is an enormous labor and haphazard excavation by backhoe can unnecessarily destroy both a septic system and homesite, making a sketch of just where a septic tank, distribution box, and drainfield trenches or pits are located is an important document to prepare and keep with a property.

Older properties: If the property is an older one but you are a new owner, you might find that the previous owner left a drawing or sketch of the location of septic system components. Ask the owner to leave any sketches with you; if they don't have a sketch but have an idea where septic components are, walk the property with them and make your own sketch.

Often we find a rough sketch of septic system component locations, at least that of the septic tank, drawn right on a basement or crawl space foundation wall or floor joist overhead where the building sewer line exits the foundation wall.

A previous service person or contractor knew that that was a reliable place to leave a drawing since anyone looking for the system in the future was likely to start by finding where the sewer line left the building.

Septic Drawings may be inaccurate: A septic system drawing is a big help, though it may be inaccurate. Even if septic system and drainfield layout drawings were filed, the "as built" drain field may not quite be the same as the plan filed since obstructions can be discovered during drain field installation. If the excavator hit unexpected bedrock, boulders, or water, may have adjusted the final location of various components to work better at the site.

The sketch at left uses a simple but accurate measurement triangle to locate the center of the septic tank.

Detailed sketch of septic component locations

The sketch at left shows that giving accurate location of septic components needs simply the identification of key components and distances. It does not have to be beautiful, to scale, nor expensive. How to Measure the Distance From the House to the Septic Tank gives details of making a septic location sketch.

Don't count on the local health department or building department to have drawings that accurately place the fields. As we explained above, the "as built" may not be the same septic plan as the "as approved".

One municipality we encountered had deliberately destroyed 50 years of septic and other building plan documents because they were tired of being pestered by homeowners wanting that information and then complaining when it proved inaccurate.

Try calling local septic system installation contractors in your area to ask if they have done work on the property.

Speak with contractors listed under Excavation, Plumbing, and Septic System Service since the excavator who has installed or worked on the property of your concern might be listed under one but not all of those categories. Neighbors may also know who has worked on septic system installations or repairs in the area.

This article series and our accompanying septic system location videos explain how to find the leach field or drainfield portion of a septic system. We include sketches and photos that help you learn what to look for, and we describe several methods useful for finding buried drainfield components. (Septic drain fields are also called soil absorption systems or seepage beds.)

More videos on septic system location & maintenance are at SEPTIC VIDEOS.


Continue reading at SURPRISING DRAINFIELD LOCATIONS or select a topic from the More Reading links or topic ARTICLE INDEX shown below.

or see SEPTIC COMPONENT LOCATIONS for help finding the septic tank, distribution box, drainfield, soakaway bed

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RECORDS to LOCATE the DRAINFIELD at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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