Residential Systems

Approximately 23% of all homes in the United States are served by private sewage treatment systems. There are approximately 9,000 private sewage treatment systems in Johnson County. The Residential On-Site Program issues permits for private sewage treatment systems where property owners are not served by a public wastewater collection system.

This program oversees the construction of new private treatment systems and the repair or replacement of existing systems.

Sewage Treatment System Design

Private sewage treatment systems typically consist of two parts, the two-compartment septic tank and the soil absorption area or lateral field. The septic tank receives and provides primary treatment for the raw sewage. Primary treatment in the septic tank is the separation of liquids and solids. Three distinct layers are formed in the septic tank: the scum layer, sludge layer and clear layer. 

Obtaining Installation Permit

Obtaining a permit to install a private sewage treatment system is a multi-step process involving applications, fees, soil analysis and inspections.

Application and Fee

A completed Soil Profile Analysis application and the current fee must be submitted by the lot owner or their authorized representative to start the permit process.  Applicable fees can be found on the Forms and Fees page.

Soil Profile Analysis

Once the application and fee have been submitted, the soil profile analysis is performed by an Environmental Health Specialist on each lot prior to the design and construction of the private sewage treatment system. The purpose of the analysis is to determine the suitability of the soil for absorption and treatment of the effluent.

The soil is analyzed to a depth of five feet. The properties of the soil, such as texture and structure, are determined as well as the depth of ground water, seasonal water table or bedrock.

A completed application, along with the fee, must be submitted by the lot owner or authorized representative before the analysis can be scheduled. The applicant is responsible for hiring a backhoe operator who will schedule the time of the analysis with the Environment Division and meet the environmental health specialist at the site.

It is recommended that the homeowner and/or builder attend the meeting on site. The backhoe operator will dig as many pits as necessary, in appropriate locations, in order to find the best soil conditions on the existing lot. Soil samples are obtained from the pits for analysis and future reference, and the pits are backfilled by the backhoe operator.

The applicant will receive a letter containing the results of the analysis and stating the options for the type of private sewage treatment system that can be permitted for that particular lot.

Plan Review

When applying for a private sewage treatment system installation permit, a second application and fee must be submitted to our office.  This application is for the Installation Permit. 

Application for System Installation

The fee can be found on the Forms and Fees page.  Along with the application and fee, the following materials must be submitted for review:

  • A completed installation application, including the site address,
  • One set of house plans, and
  • A design plan for the treatment system

The design plan for the private sewage treatment system must be prepared by a installer or designer licensed by JCDHE or a licensed engineer. The design plan shall be drawn to scale, no greater than one inch equal to fifty feet (1" = 50'), and shall include, but not be limited to, the following information:

  • Location of the soil profile pits,
  • Size of lot, dimensions, and relative location of proposed or existing structures,
  • Proposed location of the treatment system, and
  • Proposed location of a replacement area for the system, consisting of at least 5,000 square feet.

The plan review will be conducted by an environmental health specialist. The time required for the plan review will vary according to the type of sewage treatment system that has been designed. Most plan reviews can be completed within five days.

Permit for Installation

The permit to install a private sewage treatment system is issued after the plan review has been completed. The permit is approved by an Environmental Health Specialist prior to issuance to the homeowner or authorized representative.

The permit will contain the site address and specifications regarding the size and installation requirements for the private sewage treatment system. Additional specifications and requirements for the installation of private sewage treatment systems are included in the Johnson County Environmental Sanitary Code.

The permit applicant will be contacted when the permit is ready. A permit fee must be paid at the time the permit is issued. House plans that were submitted for the plan review will be returned, and the applicant will receive two copies of the permit, one to post and one to submit to the appropriate building permitting agency.

Finding a Sewage Treatment Professional

JCDHE licenses the individuals who design and install private on-site sewage treatment systems in the areas of Johnson County served by the Johnson County Environmental Sanitary Code.  JCDHE also licenses the disposal contractors, also known as pumpers, who pump and clean septic tanks and transport sewage to disposal sites.

The licenses are renewed annually. These individuals are listed on this site for the convenience of system owners. JCDHE does not endorse any particular individual or company.

Resale of Property Containing a Sewage Treatment System

Another benefit of our program is the resale inspection. This is an inspection of the existing private sewage treatment system serving a residential property, which is required to be completed prior to a property being bought or sold. The buyer or seller may request the inspections.