In 2010, the City of Kansas City, Missouri entered into a Consent Decree with the United States Environmental Protection Agency (EPA) to reduce the annual volume of overflows from the City’s sewer systems. KC Water’s Smart Sewer program is a 30-year, multibillion-dollar program to address this challenge through 2040.

Download our Smart Sewer FAQ handout or watch the short animated video below to learn more about the Smart Sewer program.

More Resources:

• How Do I Read My Water Bill?
• KC Water Common Billing Questions

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 constructed outfalls into our creeks, streams, and rivers. The discharge of water from combined sewer overflows is not uncommon, and some overflow from these systems is allowed under national discharge permits.

Separate sewer systems are not typically designed to overflow, but illicit connections, broken joints, pipes, and manholes can allow stormwater to enter the pipes, causing the separate system to overflow during heavy rainfall.

KC Water’s Smart Sewer program addresses overflows from both the combined and separate sewer systems by reducing the annual volume of combined sewer system overflows and reducing the occurrence of overflows in the separate sewer systems.

According to the U.S. Environmental Protection Agency, outfalls are locations where combined sewage exits pipes and other structures entering the environment.

Green infrastructure helps our community manage stormwater the way nature intended by capturing and utilizing rainwater where it falls. It decreases the amount of water getting into our pipes, improves water quality, and reduces flooding, pollution, and trash in our creeks, streams, and rivers.

Learn more about the KC Green Infrastructure program.

KC Green Infrastructure Resources:

• Green Infrastructure Story Map
• Green Stormwater Infrastructure Manual
• Smart Sewer Adaptive Management Plan

Inflow and infiltration (I/I) is a term used to describe rainwater and groundwater that enters sewer pipes through leaky pipe joints, broken pipes, broken manholes, and illicit pipe connections meant to carry wastewater only. Why reduce I/I?

As a part of KC Water’s Smart Sewer program, city-owned sewers and manholes in targeted areas throughout Kansas City are being restored to reduce the amount of I/I entering our wastewater system. These repairs will help protect our community’s environment by reducing the amount of stormwater and groundwater entering our separate sanitary sewer system, which will reduce the frequency of sewer overflows.

Sources of I/I

Public Vs. Private Solutions

• Public Solutions: The Smart Sewer program is working to restore sewer mains, service lateral connections and manholes throughout targeted areas of Kansas City.
• Private Solutions: Improper sewer connections on private property enable rainwater to enter the service lateral and can overload our separate sanitary sewer system. The Keep Out the Rain program finds and fixes these prohibited sewer connections for free.

No, Kansas City is separating stormwater and wastewater flows in only very small parts of its combined sewer system (less than 5%) because it is very expensive and disruptive to the public. Other cost-effective solutions to reduce overflows are being implemented within the combined sewer system.

Kansas City’s overall sewer system consists of combined and separate sewer systems. KC Water is responsible for: 

• 58 square miles of combined sewer system area
• 260 square miles of separate wastewater and stormwater sewer system area
• Approximately 653,000 people served, of which approximately 438,000 are City residents. The remaining 215,000 people reside in 27 tributary or “satellite” communities.

 Combined vs. Separate Systems

Combined Sewer System: When it’s not raining, a single pipe conveys wastewater flow to two of KC Water’s six treatment plants to be cleaned before it is discharged into the Missouri River. However, when it rains, the combined sewer system has to collect and carry both rainwater and wastewater. When these “wet weather flows” (a combination of wastewater and stormwater runoff) exceeds the conveyance capacity of the pipes in the system, it is designed to overflow diluted wastewater directly into local waterways.

Separate Sewer System: Like the name suggests, wastewater (also known as sanitary flow) and stormwater are each carried in separate piping systems in the separate sewer systems. In the combined sewer system, one solution for reducing the frequency and volume of combined wastewater overflows is to construct separate pipes to carry wastewater and stormwater. This work can be expensive and very disruptive to residents, businesses, and traffic. KC Water will be installing a second pipe system to separate stormwater and wastewater flows in ten strategic locations when it is cost-effective and other alternatives won’t sufficiently reduce combined sewer overflows. These ten locations make up less than 5% of the total combined sewer system area.

So, why separate the sewers? To help reduce the volume of combined sewer overflows and to protect our community’s environment by reducing the amount of stormwater entering our combined sewer system. On some sewer separation projects, green infrastructure is also being incorporated to treat flow from the newly separated storm sewers and to capture stormwater where it falls.

Smoke testing is used to find leaky pipe joints, broken sewer pipes and manholes, and illicit cross-connections between the separate stormwater and sanitary sewer systems. It involves blowing artificially produced smoke into the sewer system and seeing where it emerges. If the sewer is in good condition, the smoke will emerge from only manhole covers and house plumbing system vents on roofs. If the smoke emerges anywhere else, there is potential for rainwater and groundwater to enter the sewer system.

Download our Smoke Testing FAQ brochure in English or Spanish to learn more about smoke testing and what to expect if it is taking place near your property.

An easement is an area of private property that contains City-maintained infrastructure, such as water mains, sewer mains or stormwater mains. An easement is legally designated for specific uses, access, and travel-through by an entity other than the property owner. There are several types of easements including the sewer, water and public utility easements utilized by KC Water.

Download our Easement Access FAQ brochure to learn more about why crews need access to easements, who is allowed on your easement, and what to expect when work is taking place.

Water can make its way into your basement in a variety of ways. While checking for and sealing cracks in your basement walls and floor are important steps to keeping your basement dry, remember the origin of basement leaks can often be traced back to the drainage conditions outside your home. A combination of wastewater and rainwater can also backup into a building basement due to a faulty private service lateral, roof gutter downspouts and sump pumps connected to the private service lateral, when the conveyance capacity of the public sewer main is exceeded causing it to become surcharged, or when the public sewer main experiences an obstruction that limits flow conveyance and causes flow to back up into building basements through floor drains. If you believe this is the case, please report your basement backup to 311.

Download our "Why is my basement wet?" handout to help troubleshoot your wet basement and learn more about preventing future leaks.

Sewer Separation and Inflow & Infiltration Reduction

Kansas City has two kinds of sewer systems: combined and separate. Each can be a source of pollution.

• 

  In the combined sanitary system, stormwater and wastewater are collected in the same pipe and routed to a wastewater treatment plant. During heavy rainstorms or when snow melts, some of the wastewater may overflow and go directly to streams and rivers. Smart Sewer is separating portions of the combined sewer system in specific areas where it is cost effective to reduce overflows.

• In the separate system, rainwater and wastewater flow through completely separate pipe systems, one carrying wastewater to a treatment plant and the other taking stormwater to waterways.

However, leaky pipe joints, broken pipes, broken manholes, and illicit pipe connections can lead to infiltration and inflow of rainwater into the wastewater system, overwhelming capacity and causing sewer overflows and backups. Smart Sewer identifies places where stormwater enters the wastewater system and takes steps to correct, repair, rehabilitate or replace sewer systems.

Click here to view projects.

Neighborhood Sewer Rehabilitation

Cracked and broken sewer pipes in the combined sewer system that are 12-inches in diameter and smaller are being rehabilitated to restore their flow capacity and reduce the potential of sewer backups. The Smart Sewer Program’s 12 Neighborhood Sewer Rehabilitation projects were completed in 2021. Read a Smart Sewer Story to learn more about Neighborhood Sewer Rehabilitation projects.

Diversion Structure & Sewer Consolidation

As part of KC Water’s Smart Sewer program, diversion structures and sewers in the combined sewer system are being consolidated to reduce the number of places where wastewater is discharged into local streams. Consolidation projects typically result in fewer overflows during smaller rain events. Click here to view projects.

Green Infrastructure

Green infrastructure helps our community manage stormwater the way nature intended by capturing and utilizing rainwater where it falls. Green infrastructure can take many forms, depending on its location, and can be as large as a community park or as small as a rain garden. Its use in the program is to reduce the amount of stormwater entering the combined sewer system.

It also can improve water quality and reduce flooding, pollution, and trash in our creeks, streams, and rivers. Green infrastructure mimics how nature handles rainwater, increasing infiltration, evaporation, and transpiration in plants, and slowing runoff before entering the combined sewer system. It also replenishes groundwater and sustains plants, trees, and natural habitats while working with gray infrastructure to increase the capacity of our underground pipes. Green infrastructure also helps to filter pollutants from rainwater runoff before it is discharged into our creeks, streams, and rivers, thereby improving their water quality.

KC Water’s Smart Sewer program is installing a variety of green infrastructure installations in targeted areas throughout the City. Learn more about green infrastructure in Kansas City or click here to view projects.

Pumping, Storage, and Conveyance

KC Water’s Smart Sewer program is working on pumping and conveyance projects throughout our sewer systems to increase the amount of flow that can be conveyed to one of the City’s six wastewater treatment plants for treatment. These projects consist of pump station upgrades to increase capacity and reliability, as well as force main and relief sewer improvements to enable more flow to our wastewater treatment plants and reduce sewer overflows. Underground storage and conveyance pipes, above-ground storage tanks, open storage basins, and in-line storage facilities allow water to be held for a time and then released into the system once a storm passes and sewer flows recede. Click here to view projects.

Did you know an average 1-inch rainfall can produce more than 600 gallons of runoff from your roof? Installing a rain barrel can save you money on your water bill by collecting water and storing it for the dry summer months when you need it most.

Download our How to Build a Rain Barrel  handout to learn how to make one for yourself!

• Consent Decree Modification 3
• Consent Decree Modification 2
• Consent Decree Modification 1
• Consent Decree

• 2023 OCP Annual Report
• 2022 OCP Annual Report
• 2021 OCP Annual Report
  • March 2022 Program Update to City Council of Kansas City, Missouri
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• 2015 OCP Annual Report
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• 2004 OCP Annual Report

• 2020 OCP Semi-Annual Report
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  • 2013 Middle Blue River Green Solutions Pilot Project Report
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