Onsite Disposal Systems

Onsite disposal systems - also known as onsite treatment, wastewater, or sewage systems - are designed to treat wastewater effluent on the same property where it is produced. When properly managed, onsite disposal systems can effectively remove or treat contaminants such as pathogens, biochemical oxygen demand, and nutrients in human sewage. However, errors in the planning, design, installation, operation, and maintenance of these systems can lead to serious human health hazards and environmental impacts.

States have identified onsite disposal systems as the third most common contributor to groundwater pollution and a significant threat to drinking water sources. Onsite systems can have a negative effect on the environment when they are located in sensitive ecological areas or when they are installed at densities that exceed the hydraulic and hydrologic assimilative capacities of regional soils and aquifers.

If these systems fail, wastewater can migrate to aquifers or surface waters and cause significant public health or environmental problems. The following resources and guidelines for managing onsite disposal systems will help ensure that new and existing onsite disposal systems function properly.

Click through an animated and interactive model created by the Guadalupe-Blanco River Authority and Texas A&M Agrilife Extension to explore how septic systems work.


Check out the resources below for more information about wastewater in Texas and what you can do at home to improve the water quality of our region.

Learn how septic systems work, general maintenance guidelines, and what resources exist in your county to assist with septic issues.
Regular maintenance is generally less expensive than the cost of repairing or replacing a malfunctioning system.
A foul odor isn’t always the first sign of a malfunctioning septic system. Learn how to detect issues with your septic system from Texas A&M AgriLife Extension and Texas Water Resources Institute.
Even with careful upkeep, problems can arise. Click here for more resources from Texas Commission on Environmental Quality (TCEQ) - from contacting local, licensed professionals to maintenance advice.

Check out the resources below for more information about wastewater and what your organization, city, or county can do to improve the water quality of our region.

Explore EPA resources for decentralized wastewater treatment systems and advanced wastewater technology.
Find numerous options for decentralized wastewater management and their various advantages and disadvantages.
Get EPA guidance related to onsite, decentralized wastewater systems for county decision makers, planners, and local public health officials.