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On January 31, 2020, Tennessee Wastewater Systems, Inc., filed a Joint Petition with Staff of the Tennessee Public Utility Commission to increase rates for wastewater services. Service rates were last increased on July 8, 2009. Click the link below for more detail.
Full Notice
TWSI has updated statewide and Williamson County bonding rates effective September 1st (October 1st billing cycle) to reflect the latest TRA mandated true-up. These rates are expected to remain in effect until the next true-up period, which is currently is set to be every 12 months.
All Adenus Utility Customers are now able to manage their accounts online! This includes checking your balance, viewing payment history, and making online payments. It's all part of our newly enhanced customer care section of the site. Give it a try by clicking the link below.
Try it out
A piece on Adenus (our parent company) was recently aired on select TV stations across the southeast. If you missed it, you can watch it by clicking the link below.
Watch the spot

On-Site Systems was formed in 1993 to accomodate the utility needs of the emerging decentralized wastewater industry in Tennessee. In the early years, regulators and developers were slow to accept the decentralized model that On-Site Systems was looking to provide. Since the late 90s, regulatory support for decentralized wastewater in Tennessee has gradually improved as the technology has proven itself to be a viable long term option for sewering new development. On-Site Systems established the first standards in Tennessee for professionally operating and maintaining wastewater systems through refining the technology and developing a Quality Control/Quality Assurance (QA/QC) Program.


In 2003, On-Site Systems became Tennessee Wastewater Systems to better reflect the service territory the utility was serving. Tennessee Wastewater has grown considerably since that time, reflecting the acceptance of decentralized wastewater as a viable solution in the marketplace. Tennessee Wastewater is the largest decentralized wastewater utility in the state in terms of customer base, permitted systems, systems in operation, and service territory footprint. It is the flagship utility for our industry and has created the blueprint for sustainability that many other utility districts, municipalities and service providers have since adopted. As Tennessee Wastewater approaches its 25th anniversary, we are reminded of the strides our industry has made and anticipate a very bright future in the years ahead.

(pictured above): the current Adenus office on Aviation Pkwy

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851 Aviation Parkway
Smyrna, TN 37167

Utility Customer Care: 888.3.ADENUS
Maintenance Hotline: 877.669.0786