JoCo Inflow

JoCo Inflow Logo

One of Johnson County Wastewater’s major investments to improve wastewater collection system performance is its Private Inflow and Infiltration program, now known as JoCo Inflow.

This voluntary program has helped thousands of Johnson County homeowners reduce the risk of basement sewer backups with no out-of-pocket expense to the homeowner

Thousands of private sewer lines are connected to the wastewater system. For the system to function properly, those private connections must be properly configured and maintained. 

Inflow and Infiltration occurs when rain and groundwater enter the sanitary sewer system. This excess flow should go into the storm sewer system, so when it enters our sanitary sewer system it overwhelms the system and results in private and public systems issues. This is a common theme for many wastewater utilities across the country, and addressing the excess wet weather flow requires public support and participation to mitigate the issue.


JoCo Inflow: How it works

What causes Private Inflow and Infiltration?

Private I&I is caused by the connection of sources on private properties (sump pumps, downspouts, area/driveway drains, uncapped cleanouts, foundation drains) to the public collection system.   

Private I&I reduces capacity in the sewer system. This can overwhelm the sewers with stormwater flow which can lead to: 

  • Basement backups 
  • Sanitary sewer overflows to adjacent watercourses 
  • Increase treatment costs 

What can I do to fix this?

Wastewater has implemented a 100% voluntary program called JoCo Inflow that will help remedy this problem at no cost to the homeowner

The program started in 1983 and expanded in 1986 creating the first large scale private I&I removal program in the United States. Since then, we have inspected more than 55,000 properties and removed about 17,000 sources. Currently, Wastewater removes approx. 150-200 private I&I sources per year. 

Get Started


See If Your Home Qualifies

Properties within the Johnson County Wastewater service area may have been constructed with a private I&I connection allowing unwanted groundwater to enter the sanitary sewer. 

Complete this form to schedule a time for a JoCo Inflow representative to perform an evaluation.

A JoCo Inflow representative will perform an evaluation of your property with no out-of-pocket expense to determine if your home qualifies. 


Schedule Maintenance Work

If we find that your property’s connection to the sewer system needs maintenance during the evaluation, you may select a plumbing company from a list of pre-qualified plumbers provided by Wastewater.


Choose Your Plumber

Wastewater has a list of qualified local plumbers who are experienced with these repairs and can perform the work on your property. If you have a plumber not listed that you would like to have perform the repairs, please contact the Wastewater representative and they can discuss the procedures for contracting with your plumber.


Work Is Completed

The plumber will schedule the work at a time/date agreeable to the property owner. The work typically takes one business day to complete.



Wastewater or an authorized representative will verify the work was done properly.

How does the sewer system work?

Wastewater Sewer Basics
  1. Manholes grant access for cleaning and inspecting sewer lines. They can join pipelines that would otherwise not connect due to elevation differences.
  2. Sewer Mains receive sewage from lateral lines and use gravity to channel sewage toward the treatment plant. They are sometimes referred to as gravity mains.
  3. Sewer Laterals connect properties to the public sewer system and are typically the property owner’s responsibility.
  4. Lateral Clean-outs give access to lateral lines and can be found in yards, basements and crawl spaces.
  5. Interceptor Mains receive the contents of the sewer mains, carrying the effluent to the treatment plant. These are generally the largest lines within a collection system.
  6. Pump Stations move wastewater when gravity conveyance is not an option.
  7. Force Mains connect a pump station to an interceptor sewer.
  8. Wastewater is cleaned at the treatment facilities using a series of basins.
  9. Outfalls discharge treated water back into the environment.

Frequently Asked Questions

Why did Wastewater create the JoCo Inflow Program?

Johnson County, like many other municipalities across the nation, has identified the strain that additional rainwater and groundwater adds to the sanitary sewer system. The sanitary sewer system was designed to convey domestic sewage to the wastewater treatment facility and does not have the capacity to convey and treat wet weather flows. During periods of moderate or heavy rainfall, sewer systems can reach capacity, overflow, and discharge a mixture of wastewater and stormwater out of manholes or backup into basements. Separate sewer systems are not typically designed to overflow, but illicit connections on private property, broken joints, pipes and manholes can allow stormwater to enter the pipes, causing the separate system to overflow during heavy rainfall. The JoCo Inflow program is designed to identify and eliminate illicit connections on private property and ultimately reduce the excess wet weather flow.

What is causing the excess flow in the sewer system?

The sanitary sewer system in Johnson County is designed to carry the wastewater that flows from homes and businesses and is not designed to handle storm water. Due to the age of the system, past construction practices, and system deterioration, groundwater/stormwater leaks into the system. The sanitary sewer system becomes overloaded during heavy rain events and the system surcharges and overflows into streams and creeks and backs up into basements. 

What is sewer overflow?

During periods of moderate or heavy rainfall, sewer systems can exceed capacity, overflow, and discharge a mixture of wastewater and stormwater out of manholes or backup into basements. Separate sewer systems are not designed to overflow, but illicit connections on private property, broken joints, pipes and manholes can allow stormwater to enter the system, causing the separate system to overflow during heavy rainfall. The JoCo Inflow program is designed to identify and eliminate illicit connections on private property and ultimately reduce the excess wet weather flow.

Why should I participate in the JoCo Inflow Program?

Participation in the JoCo Inflow program will help reduce unwanted groundwater and stormwater from entering the sanitary sewer system. These efforts aid in reduction of flows to the Wastewater treatment facilities and will help protect properties from sewer backups. Eliminating wet weather-induced flows reduces the volume of rainwater being transported through the system and ultimately the costs associated with treating the excessive flows. Studies conducted by Wastewater, and other communities across the country, have proven that eliminating these connections from private property is much more cost effective than the alternative of building larger sewer pipes and treatment facilities.

What does the evaluation process look like for my property?

The property owner will receive a letter in the mail asking for participation in the JoCo Inflow program; this is a voluntary program with no out-of-pocket expense to the property owner to reduce rainwater and groundwater from the sanitary sewer system. The letter will come from Wastewater and will be addressed to the owner per county records. In the event the property is a rental, the owner or tenant can schedule the evaluation.

Complete this form to schedule a time for a JoCo Inflow representative to perform an evaluation.

An evaluation crew will visit the property and inspect the basement or crawlspace area, walk around the outside of the house, take photos, and ask questions regarding the history of the property as related to stormwater runoff and the sanitary sewer. The focus of the evaluation will be on the basement, crawl space (floor drains, sump pumps) and exterior of the property (area drains, driveway drains and downspouts). 

If you do not have any of the listed features, participation in the program is still beneficial to the program and will provide valuable information. If you think your property is compliant (no stormwater/groundwater connections to the sanitary sewer system), Wastewater would still like to confirm this by conducting an evaluation. 

What happens if the property needs a JoCo Inflow repair? What is the process?

This program is 100% voluntary. If a source is identified, you will be notified and can choose to move forward with the repair.

You will have the ability to select a plumbing contractor from a list of licensed, prequalified plumbers to complete the work or you can elect to have the program manager assign one for you. There may be a need for the selected plumber, property owner and project representative to meet at an agreed time and date to review the repair procedures to ensure all parties are informed. After the consultation, the plumber and owner will schedule a day(s) for the work to be completed. Once the work is complete, a project representative will verify that all work was done to specifications and meets Wastewater standards. All repairs completed under the program will have a one-year warranty provided by the selected plumbing contractor. 

How much will it cost to participate in the JoCo Inflow Program?

There is zero out-of-pocket expense to participate in the JoCo Inflow Program. Wastewater will pay the selected plumbing contractor directly for all approved repairs. 

Is participation in the JoCo Inflow Program mandatory?

No. The JoCo Inflow Program is a voluntary program. Participation is highly encouraged to reduce wet weather flows and to reduce the need and cost of larger capital projects. 

Reduction of the unwanted wet weather flows may also reduce the chances of future basement backups for you or your neighbors.

My home doesn’t have a stormwater connection to the sanitary sewer. Do I need to participate?

All properties within the project area need an evaluation even if the property does not have a stormwater connection to the sanitary sewer.

What else is Wastewater doing to address the problem?

Wastewater has a routine cleaning program to remove blockages that could restrict flow, systematically repairing sewer pipes and manholes, and upgrading pump stations and treatment plants. Wastewater makes a concentrated effort to take a cost-effective approach to maintain affordable rates. 

Is this problem unique to Johnson County?

All sewer agencies face the challenge of maintaining a sanitary sewer system that prevents the introduction of groundwater/stormwater during heavy rain events. Many municipalities across the county are taking measures to either reduce groundwater/stormwater from their systems or build systems large enough to handle the excess flows.

My family/friends did not receive a notice, why not?

Wastewater is taking a strategic approach to repairs to the system and has identified the highest priority areas that have a greatest amount of groundwater/stormwater that’s entering our system. We will be working in these areas to identify and remove sources of groundwater/stormwater from the system. You can refer family and friends to the Wastewater website to get more information. 

Who can I contact to get more information on the program?

You can get more information on the Wastewater website or contact a JoCo Inflow program team representative by calling 913-715-8550 or emailing

How is this program being funded?

Wastewater has budgeted for repairs to the system, and all work performed under the JoCo Inflow program will be funded by Wastewater.  

How long does the repair process take to complete?

Most repairs can be completed within one business day and will be performed on a mutually agreed date and time. 

Can I have the plumbers do additional work while they are on my property completing a repair?

A property owner can have the plumbing contractor perform additional work as negotiated and paid for by the property owner. Wastewater will only pay for designated approved repairs under the program. 

What happens if I choose not to participate?

The JoCo Inflow program is voluntary. Failure to reduce wet weather flows will require Wastewater to make system improvements that are more expensive and could result in higher customer rates.  

Who is the JoCo Inflow team representative who will perform the evaluation and will they have ID?

The JoCo Inflow team is made up of Wastewater staff, and consultants, which include TREKK Design Group and HDR Engineering. Each team member will have an ID badge on their person indicating they are an authorized JoCo Inflow contractor or Wastewater employee.

Who is responsible for the general maintenance and upkeep of JCW’s sewer easements?

The property owner retains the right to use the surface of the sanitary easement, so long as the use does not interfere with the installation and maintenance of the sanitary and no buildings or structures are erected within the easement. The property owner is responsible for mowing and general upkeep of the easement area.