Purdue Residential Onsite Wastewater Disposal:  Septic system information to protect your family and the environment

Designing a New System

It is very important to make your septic system large enough for possible future needs. In the future, you might:
  • Install a jacuzzi
  • Have lots of babies
  • Sell your home to a larger family
  • Take in several orphans
  • Care for your elderly parents
  • Start a laundering service
  • Develop a case of chronic diarrhea!

Men with plan
Your contractor must design your septic system so it can handle the flow, both now and in the future. Many site-specific factors must be considered.

RWASTE V: Indiana Onsite Wastewater System Design

This program should give you a better idea of what your contractor has to consider when designing your septic system. RWASTE V recommends a specific type of system best suited to a particular set of site and soil conditions, and provides specific design information. The program estimates the amount of gravel needed for construction as well as suggesting system layouts which will best fit the shape and size of disposal area available. The program will also size the pump and piping needs for pressure distribution systems. The design recommendations must then be reviewed and altered to fit the actual features of the site by a consulting engineer.
Click to begin RWASTE V

Click to begin RWASTE V


Educational Tutorials

If you want to learn more about conventional septic system design, see this tutorial:

Purdue Extension Publications

The Purdue University Cooperative Extension Service has published several booklets on proper design and construction of the home septic field. These publications are available from the Farm Building Plan Service and are also available in html format:
Typical conventional septic system.

SAMPLE DESIGN: Typical conventional septic system.