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Home Buyer's Detailed Guide to Septic Systems - Buying a Home With a Septic Tank SepticAPedia ©

• Advice for buyers of a home with a septic system - what to do
• What is a septic system - how it works, what goes wrong
• What to ask about a septic system when buying
• How to make a visual inspection of the septic system
• How to test the septic system - dye testing, loading, probing
• When to pump the septic system - before purchase
• Where to get information about the septic system

This website answers just about any question you might have about buying or owning a house with a septic system.

This section gives critical advice to people buying a home with a septic tank and drainfield or similar septic systems. This home buyer's guide to septic systems tells what inspection, testing, and maintenance are recommended when buying a home with a private septic system. Learning a little about how septic systems work (described here) and about septic cleaning (removing septic waste), and testing a septic system before buying a new home can help you avoid installing a septic system or replacing the septic system as a big surprise.

Septic systems include buried septic tanks (sewage tanks) and drainfields - expensive and hidden from view such as in the photo at left. This document provides advice for home buyers who are buying a home with a private septic system: homes using a septic tank and drainfield or similar soil absorption system.

Here we explain how to reduce the risk of a costly surprise by asking questions, visually inspecting the septic system, and by testing the septic system. Chapters 1,2,3 in this file explain what a septic system is and outline step by step septic inspection and testing for home buyers.

Other chapters of this guide explain what goes wrong with septic systems, 5-recommends and describes septic inspection and test methods in more detail, explains how to be sure your septic inspection and septic test are conducted properly, tells you where to get more septic system information about a given property, and warns of unsanitary or dangerous site conditions.

If you need to know how to install a septic system, or if you find that you have a sewage pit (cesspool) this website provides articles explaining those topics too.

© Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

1-INTRODUCTION: to buying a home with a septic tank

2-YOU NEED TO KNOW AND DO: How Septic Systems Work. Here is the minimum you need to know and what you need to do (or have done) when buying a property with a septic system

Because of the potential repair/replacement costs involved, and because the system is buried and cannot be exhaustively inspected and tested, you want to do what you can to evaluate the condition of the septic system before you complete the purchase of the property.

Here's what to do: If you are buying a home with a septic tank and drain field, here's what you need to do, as succinctly as possible. Each of these steps is described in more detail below, and in even more detail in linked-to documents. Steps 1 and 2 are essential. Step 3 is usually a good idea. Step 4 depends on the results of steps 1,2,3 but is usually a good idea. Step 5 is not usually done but might be necessary. Step 6 is what you do if you're being really thorough.

Synonyms for "septic system" used by the general public include septic waste system, sewage systems, and water sewage systems, even Roman sewage systems. All of these refer to onsite systems which hold and separate sewage waste from its liquid effluent which is treated further and then disposed-of by any of a variety of means which we will discuss. At this site we also discuss special considerations for handling septic waste such as garbage disposal septic tank waste volume and what to do about it.

1. Ask About the Septic System - where is it, what's installed, what's the service and repair history
2. Make a Visual Site Inspection for signs of trouble
3. Perform a Septic Loading & Dye Test to see if it produces evidence of a failure. Hire a home inspector who knows how to perform and will include this test.
4. Pump the Septic Tank and inspect for additional clues, depending on what you learned at 1,2,3
5. Additional Septic System Physical Investigation might be needed
6. Get Outside Information Sources about Septic Systems if you're being really thorough
7. Neighboring Septic System Problems - advice for dealing with a neighboring septic system producing odors or seepage

The six home buying steps listed above are explained in detail at 5-HOW TO INSPECT & TEST but first you might want to review the basics about septic systems at 3-SEPTIC SYSTEM COMPONENTS and also 4-WHAT GOES WRONG.

3-SEPTIC SYSTEM COMPONENTS - the Basic Parts of a Conventional Septic Tank and Leachfield

The purpose of a septic system is to retain solid waste in the tank and to dispose of effluent waste water into the ground without contaminating the environment.

To accomplish this a septic system consists of the elements shown in the sketch above. In simplest terms, a septic system consists of a holding tank which retains solid waste and grease from household waste water, and an absorption system or "leach field" which disposes of liquid wastewater or "effluent" which leaves the septic tank for absorption below ground into soils at the property.

Let's just outline these main septic system parts in a little more detail:

1. The main waste line or "sewer line" connects the home's plumbing to the septic tank.
2. The septic tank which is often buried just a few feet from the house foundation wall, receives all waste (solid and liquid) and has the main job of retaining solids and grease. Solids settle to the bottom of the tank as sludge. A floating scum and grease layer forms at the top of the tank. Baffles at the tank inlet and outlet reduce the velocity of liquid moving through the tank and prevent solids and floating scum from leaving. Clarified effluent is allowed to flow out of the tank into a soil absorption system. In some states (Connecticut since January 1991) septic tanks now consist of two compartments in order to do a more effective job.
3. A effluent distribution pipe direct the flow of effluent from the septic tank to the leaching system, often connecting first to one or more distribution boxes which in turn distribute flow of effluent evenly into the leaching system.
4. A leaching system, or soil absorption system, also called "drainfield", a soakaway system, leachfield, or seepage bed disperses the sewage effluent into the surrounding natural soils. There are many types of leaching systems but the most common is a network of perforated pipes buried in gravel-filled trenches. The specific type utilized on a particular property depends on the soil conditions and the amount of space available.
   
   Galleries or "septic galleys", seepage pits and sand beds have historically been used.
   
   Most distribution piping and leaching systems are "gravity" systems, meaning the flow runs through piping and distribution boxes without the assistance of any mechanical device, such as a pump or siphon, but some homes pump their effluent uphill into a mound system.
   
   Advanced wastewater treatment systems are also available to handle difficult sites.
   

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Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

HOME BUYERSGUIDE
1-INTRODUCTION
2-YOU NEED TO KNOW AND DO
3-SEPTIC SYSTEM COMPONENTS
4-WHAT GOES WRONG
5-HOW TO INSPECT & TEST
  5-1. ASK ABOUT THE SYSTEM
  5-2. VISUAL INSPECTION
  5-3. LOADING & DYE TEST
    WHAT'S A DYE TEST?
    TEST LIMITATIONS
    FLOODING TESTS
    PROBE TESTS
  5-4. PUMP THE TANK
  5-5. ADDED INVESTIGATIONS
  5-6. ASK OUTSIDERS
  6-FINAL OVERVIEW
  SEPTIC FAILURE LAWSUIT

More Reading

• Sketches of the Septic System Components Private Sewage Disposal Systems - Septic Drawing Library
  Septic Systems - an Engineer's View
  Septic System, Septic Tank, & Cesspool Safety Warnings for Septic Inspectors, Septic Pumpers, and Homeowners.
  CESSPOOLS if you don't know what they are.
  Don't Flush these things into a septic system
  DRYWELLS if you don't know what they are.
  SEPTIC SYSTEMS ONLINE BOOK Online Book, Inspection, Test, Diagnosis, Repair, & Maintenance: Our Online Septic Book: Septic Testing, Loading & Dye Tests, Septic Tank Pumping, Clearances, details of onsite waste disposal system inspection, testing, repair procedures.

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building design, inspection, and repair, and about indoor environment testing, diagnosis, and cleanup are at the InspectAPedia Bookstore.
• ...

More Information on Building Diagnostic Inspections and Repairs

• The Septic System Information Website
• Directory of Professional Inspectors available via Internet (Some of these inspectors offer septic system testing and inspection)
• Diagnosing Clogged Drains: A First Step for Homeowners
• Performing a Septic Loading and Dye Test - How to perform this test (separate document)
• Septic Tank Pumping Guide: When, Why, How to pump the septic tank
• Table of Required Septic Tank Sizes: Septic Tank Capacity vs Usage in Daily Gallons of Wastewater Flow & How to Calculate the Size (in gallons) of a Septic Tank.
• Septic Systems - an Engineer's View
• How Big Should the Leach Field Be? - table of soil percolation rate vs. field size
• Home & Outdoor Living Water Requirements
• Table of Required Clearances: Distances Between Septic System & Wells, Streams, Trees, etc.
• Septic System Inspection Methods and Procedures, - online illustrated class for building and septic inspectors
• Septic Systems Inspection, Testing, & Maintenance- online textbook. Detailed how to inspect, maintain, repair information

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