On-site Sewage Disposal System

Your Septic System

If the location of your home in Pueblo West is zoned A-3, you will be responsible to build and/or maintain your own septic system. It is one of the home ownership responsibilities that can have environmental consequences far beyond the boundaries of your property.

The technology employed in traditional on-site sewage disposal systems has been in use for many decades. A septic tank provides a place for the wastewater flow to slow down so that the solids can settle out. The remaining wastewater flows into the leach field where it percolates through soil, which cleanses it. It’s simple but only works if you follow the rules.

Groundwater Contamination Risk

The State of Colorado has empowered local Boards of Health to enforce the rules of on-site sewage disposal systems through the county Health Departments. These rules are very important because septic systems, if not installed or maintained properly, have the capacity to contaminate ground water.


The most common cause of septic system failure is lack of proper maintenance. A professional engineer or the Pueblo County Health Department will consult with you on design and installation, but maintenance is strictly up to you the homeowner, and maintenance is critical. A good recommended interval for having the septic tank pumped is about every five years. The Pueblo County Health Department can provide a list of licensed septic pumpers, or check the yellow pages in your telephone book. Whatever the pumping process costs, it is cheaper than the major expense of replacing a failed system.


If a septic tank fills up with solids, the solids will reduce the available tank volume to the point where solids are discharged in the outlet of the absorption field. Once in the leach field, the solids clog the soil openings (pores) and block the flow of liquid into the soil. This causes the system to fail and a major expenditure is required to replace the system.

Permitting a New Septic System

There is really only one reason for building a new septic system - the building of a new residence where there was no residence before. Colorado State Law 25-10-111 requires that before a person constructs, remodels, occupies or maintains any dwelling, building, or structure he must first complete a permit for an individual sewage disposal system.

Starting the Process

This process begins at the Pueblo County Health Department. You will need to bring in a current soil percolation test (a perc test) done by a Colorado Registered Professional Engineer, and you will need plans showing the maximum number of bedrooms in the proposed dwelling. Due to the information that will be asked, you should have the engineer contact the Health Department for details.


As the property owner, you may install your own system or you must use a licensed contractor. A list of currently licensed contractors is available from the Health Department.

Assistance & More Information

There are a variety of subtleties in this process. The County Health Department staff can make the intricacies of the process seem a little less intimidating.