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Phone: 913-715-8500

11811 S. Sunset Drive, Suite 2500, Olathe, Kansas 66061

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Engineering Public Projects: DLSMB Cogeneration

In May 2009, federal, state, and local officials broke ground on the largest "green infrastructure" project in the State of Kansas to be funded by the American Recovery and Reinvestment Act (ARRA) of 2009 -- nearly $18 million in a series of improvements to Johnson County's Douglas L. Smith Middle Basin Treatment Plant (DLSMB).

The facility is located in Overland Park, bordered by commercial and residential development. Originally constructed in 1979, it was recently expanded from 12 million gallons per day (MGD) to 14.5 MGD and upgraded to meet strict nitrogen and phosphorus effluent goals. As a result of that expanded liquid treatment capacity, additional solids processing capabilities were needed. Thus plans were developed to expand the anaerobic solids treatment system.

This project was “shovel ready,” which was a requirement for funding when the ARRA was approved in 2009. Through the Environmental Protection Agency's State Revolving Fund program, administered by the Kansas Department of Health and Environment, this project was awarded $17.8 million as a “green” project with $8.1 million of this amount as principal forgiveness or in other words, a grant.

The co-generation facility at the Douglas L. Smith Middle Basin Wastewater Treatment Plant produced 7,014,000 kWh of green power (power produced off the grid) in 2013.

The project was originally borne of the desire to increase solids handling capacity while reducing the carbon footprint. In December 2007, the Johnson County Board of Commissioners passed a resolution to reduce greenhouse gas emissions by one third by 2020, County-wide by 80 percent by 2050, and to reduce GHG from energy use in new and largely renovated County buildings to zero by 2030. The project, built by contractor BRB Contractors, Inc. of Topeka, Kan., was officially approved by the Johnson County Board of Commissioners in March 2009.

Components of the treatment plant improvements included the construction of a new anaerobic digester, a FOG (Fats, Oils and Grease) station to more efficiently receive and treat used greases and oils from restaurants and industries, and a cogeneration system to produce virtually all of the plant's annual operating energy from captured biogases.

This project has attracted a good deal of attention, starting with the groundbreaking ceremony attended by dignitaries from the Kansas Department of Health and Environment, U.S. Environmental Protection Agency, Johnson County, and several media crews from local newspapers and TV stations.

  • The Environmental Protection Agency had a film crew out to shoot video to put on their website.
  • In February 2010, Craig Hooks, assistant administrator for the EPA Office of Administration and Resources Management, made a site visit to tour the project. Prior to his visit, he had recently highlighted this project during testimony on Capitol Hill (page 5) regarding EPA’s progress in implementation of the ARRA program in 2009.
  • At the summer meeting of the National Association of Clean Water Agencies, this project received the National Environmental Achievement Award.
  • Kansas City’s KCTV Channel 5 featured this project as a part of its investigation series, Road to Recovery? Going Green.
  • This project also made Vice-President Biden’s list of “100 Recovery Act Projects that are Changing America.”
  • MARC Sustainable Success Stories Award
  • NEHA Sustainability Award

Engineering Public Projects - Gardner Lake: Frequent Questions

General Questions

Q: If I sign the petition for sewers, do I have to connect to the sewer system?

A: No. You can decide if and when you would like to connect.

Q: What are low pressure sewers?

A: Low pressure sewers are sewer systems where each individual home has its own grinder pump unit which pumps into a pressurized system, which in turn, flows into a nearby conventional gravity sewer system.

Q: Why can’t we have regular gravity sewers?

A: Gravity sewers are not suitable for most lake communities. Low pressure sewers were designed to be used in lake communities.

Q: Can sewage be pumped into my house from the main line?

A: This is very unlikely as there are two check valves in the system between the main and the house to prevent this from happening.

Q: If the sewer district is created, is there any way to have the district creation documents require that Gardner Lake residents have a vote on any future annexation proposed by Gardner?

A: No. Current state statutes do not allow Gardner Lake residents a right to vote on future annexation proposals by the City of Gardner and the sewer creation documents cannot require it.

Q: Is the grinder pump unit (GPU) noisy enough to be heard?

A: No. The GPU is very quiet and can’t be heard unless you stand directly over it. Even then, it is very quiet.

Q: Which portion of the system is my responsibility?

A: The four inch service line that goes from the home to the grinder pump unit is the responsibility of the homeowner. The pump, control panel, discharge line, and main line are all maintained by Johnson County Wastewater.


Q: Must I pay for maintenance or replacement of the pump?

A: No. There is no separate charge for this service. Johnson County Wastewater pays for normal maintenance and replacement of the grinder pumps. Funds for this are collected with the bi-monthly user charges paid by all Johnson County Wastewater customers.

Q: How reliable are low pressure sewers?

A: This is a very reliable technology that has been used widely for over 30 years. Johnson County Wastewater has around 350 pumps in use today, dating back to 1998. Based on this experience, on average, a home with a grinder pump will have a maintenance call once every five years. Johnson County Wastewater's maintenance provider typically responds within two hours on every call and will restore service very quickly once they arrive.

Q: Whom should I call if there is a problem with my grinder pump unit?

A: Every control panel displays the 24 hour service phone number of our maintenance provider. Currently, every year Johnson County Wastewater sends out a letter and refrigerator magnet with the maintenance number listed.

Q: How do I silence my alarm once it has activated?

A: There is a button on the bottom of each control panel. Once you push it, the audible alarm will stop. However, the visual alarm will stay lit.


Q: What happens if the electricity goes out?

A: First, you need to reduce water use as much as possible because there is limited storage in the pump unit, and if that storage is exceeded, the sewage will back up into your house. If the power is out for more than four hours, please call the 24 hour service phone number and a technician will be sent to hook a generator to your pump to pump it down. The technician can pump down the system twice a day, but due to limited storage in the pump unit, they are only pumping out about 30 gallons at a time. So, you should reduce water use as much as possible.

Q: How much electricity does the grinder pump unit take to operate?

A: According to the manufacturer, it takes the same amount of electricity to run a 40 watt light bulb 24 hours a day, or about $28 per year.

Q: What is the required capacity of the electrical circuit to accommodate the GPU?

A: 240 volts, and 20-30 amps. It may be necessary, at the homeowner’s expense, to upgrade to a 100 amp service if the existing service is less than 100 amp.


Q: Will the streets be repaired if the sewer line cuts through them?

A: Yes. Under the construction contract, the contractor must repair the roads, where they are damaged by the construction work, back to their original state.

Q: Where will the main lines be installed?

A: Generally, the mains are installed parallel to streets in street right-of-way, but not in the streets, except at locations where the main crosses the street.

Septic System

Q: If the sewers are installed and my septic system/holding tank is failing, will I have to connect to the existing sewers?

A: Yes. If there is a major problem with your septic system or holding tank, you will be required to hook to the existing sewer system at that time in accordance with the Johnson County Environmental Code under the jurisdiction of the Johnson County Health and Environment Department.

Q: Our home has a separate grey water (clothes or dishwater) discharge. Will these flows be directed to the sanitary sewer system?

A: Yes. If you decide to connect to the sewer system once the main lines are in, you will be required to reroute all wastewater to the grinder pump unit at that time.

Q: If I sell my house, must I have an inspection of my septic system?

A: Yes. Under county code requirements, every time a house changes ownership in the unincorporated area of Johnson County, the septic system must be inspected by the Johnson County Health and Environment Department.

Q: What happens if the Health and Environment Department finds a problem with the septic system?

A: If it is a minor problem, like a missing baffle or tee in the tank, it can be fixed without major expense. However, if there is sewage surfacing or a cracked tank, then a holding tank will be required if the property is within 200 feet of the lake. Also, if a sewer is available, the property owner will have to connect at that time.


Q: What happens if the cost of the project is greater than what is budgeted for the project?

A: Prior to the initiation of construction, if it is determined the project cost exceeds the budget cost by more than 10 percent, all property owners in the district will be notified of a public hearing to reconsider the project. After the hearing, the Board of County Commissioners will determine whether to complete the project. If the Board does not authorize completion of the project, any costs for engineering, right-of-way acquisition, etc. incurred, will be assessed to the properties in the district. If the Board authorizes completion of the project, property owners will be assessed the higher costs.

Q: How much does the grinder pump unit cost?

A: Currently, these pumps cost around $3,500 each. The total amount of an installed unit is approximately $7,500 to $8,500. This is a cost financed by the homeowner, not Johnson County Wastewater.

Q: How much will I have to pay if the sewer system is approved?

A: Every assessed lot would pay an estimated lump sum amount of $2,148. You can also choose to have this cost put on your tax bill over a 20-year period at an estimated 2.75 percent interest rate. The resulting estimated amount would be $141 per year for 20 years.  If the final cost of the project is more or less than these estimates, you will be assessed the actual costs.

Engineering Overview: Maps

Consolidated Main Sewer District Map

Johnson County's existing sanitary sewer infrastructure dates back to 1946. To help maintain this system and keep pace with Johnson County's rapid suburban development, Johnson County Wastewater uses new and emerging GIS (Geographic Information Systems) technology. Such systems enhance the ability to quickly access information concerning Johnson County Wastewater's infrastructure without the use of paper maps. Detailed information on the sewer system engineering records can be accessed through Johnson County's AIMS website. Be assured that our information is current as the databases are updated daily.

AIMS (Automated Information Mapping Systems) is the name of Johnson County's GIS. Current and future utilization of AIMS and Johnson County Wastewater's AIMS data layers greatly enhance staff's ability to access up-to-date information concerning the department's infrastructure without the use of paper maps. The use of GIS reflects a collaborative effort that uses data from city, county, regional, state, and federal resources.

Kansas Open Records Act Policy - Please Read Carefully

"No person shall knowingly sell, give or receive, for the purpose of selling or offering for sale, any property or service to persons listed therein, any list of names and addresses contained therein, or derived from public records..." K.S.A. 21-3914. Violation of this law is a Class C Misdemeanor and can subject the violator to prosecution and imprisonment up to 30 days and a fine of $500. Violators will be reported for prosecution. By accessing this site, the user makes the following certification pursuant to K.S.A. 45-220(c)(2): "the requester does not intend to, and will not:

  1. Use any list of names or addresses contained in or derived from the records or information for the purpose of selling or offering for sale any property or service to any person listed or to any person who resides at any address listed; or
  2. Sell, give, or otherwise make available to any person any list of names or addresses contained in or derived from the records or information the purpose of allowing that person to sell or offer for sale any property or service to any person listed or to any person who resides at any address listed."

Johnson County Wastewater Data Disclaimer - Please Read Carefully

It is understood that while the Automated Information Mapping System's (AIMS) participating agencies and information suppliers have no indication and reason to believe that there are inaccuracies in information incorporated in the base map, AIMS AND ITS SUPPLIERS MAKE NO REPRESENTATIONS OF ANY KIND, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE, NOR ARE ANY SUCH WARRANTIES TO BE IMPLIED WITH RESPECT TO THE INFORMATION, DATA, OR SERVICE FURNISHED HEREIN.

In no event, shall Johnson County Wastewater become liable to users of these data, or any other party, for any loss or damages, consequential or otherwise, including but not limited to time, money, or goodwill arising from the use, operation, or modification of the data. In using these data, users further agree to indemnify, defend, and hold harmless Johnson County Wastewater for any and all liability of any nature arising out of or resulting from the lack of accuracy or correctness of the data or the use of the data.

To assist Johnson County Wastewater in the maintenance of the data, users should provide their department information at the address shown below concerning errors or discrepancies found in using the data.

Johnson County Wastewater
Attn: AIMS Coordinator
11811 South Sunset Drive, Suite 2500
Olathe, KS 66061-7061

  • Please acknowledge Johnson County Wastewater and AIMS as sources when this data is used in the preparation of reports, papers, publications, maps, and other products.
  • To ensure that appropriate documentation and data limitations are provided, these databases should not be redistributed to any other parties.


  1. You must be a JCW  customer or property within JCW service area.
  2. Your home must have experienced a confirmed sanitary sewer basement backup as a result of an intense rain event.
  3. The backup must have been the direct result of capacity problems in the sanitary sewer system.

This program is intended to help protect your home from future backups during heavy rains. A backup device or plumbing modifications will not resolve:

  • Sanitary sewer service lateral issues (roots, cracks or broken pipe.)
  • Basement water problems caused by cracks in walls, floors, window well leakage and surface water flooding.

>> Getting started

Contractor Qualifications

Johnson County Wastewater has compiled a list of contractors for your convenience only. Contractors on the list are interested in the program and have attended an informational meeting about the program.

You’re not obligated to employ a contractor on the list. You have a right to obtain a bid from any contractor.

Contractors performing work under this program shall maintain commercial general liability, including completed Operations coverage with a minimum limit of $500,000 combined single limit property damage and bodily injury liability, and Worker's Compensation coverage, if required by the State of Kansas or Missouri, depending on the place of business. Missouri contractors who maintain Worker's Compensation coverage shall have an "All States" endorsement included on their coverage.

Johnson County Wastewater does not endorse or recommend contractors for the purpose of installing backup prevention devices or the installation of sewage ejector pump systems. Any contractor who generates numerous complaints from property owners or neglects to perform quality workmanship shall be removed from the list at the discretion of Johnson County Wastewater.


JCW does not specify any make or model of backup prevention device or preferred method.

  • The contractor is responsible for all permits and city inspections.
  • The plumbing contractor should take photos of the work and provide copies with the plumber’s final invoice.
  • All work performed under the Backup Prevention Program will be warranted by the contractor for a period of not less than one (1) year following the date of installation.

>> Recommended annual maintenance on the Backup Prevention Device

Common Options for Backup Prevention

JCW’s Backup Prevention Program is voluntary and options should be discussed with your plumbing contractor. There is no one size fits all option .

JCW does not specify any make or model of backup prevention device or preferred method

Backwater Valve Options

A contractor may recommend a backup prevention valve on the sanitary sewer service line (typically before it exits your home). The contractor will remove small portion of your basement floor to expose the service line and install the valve. The valve will require regular maintenance, so we recommend putting the valve in a location that’s easily accessible.

Typical Backwater Valve Installation

Typical Backwater Valve Installation

JCW recommends discussing the type of valve the plumber recommends. Links to websites for some common backwater valves below:

Sewage ejector pump

A contractor may recommend a sewage ejector pump as an alternative to a backup prevention valve when floor and laundry drains are the only basement plumbing fixtures. Sewage ejector pumps go in the basement. The drain lines from the floor drains and sinks are connected to its basin. The pump inside the basin has a float system that when activated will move solids and liquids to a higher elevation before it enters the home’s sanitary plumbing again.

Typical Sewage Ejector Pump Installation

Typical Sewage Ejector Pump Installation

>> Contractor qualifications