Wastewater Department


Collection System

The collection system is comprised of 5 lift station and about 22 miles of sanitary sewer main ranging in size from 6”-15” diameters.  The city is responsible for maintaining the sewer mains with the use of its trailer mounted jetter unit as well as contracting out root cutting and cleaning services to maintain the integrity of the sewer system.

Treatment Plant Overview

The wastewater treatment plant currently has a design daily flow of .680 MGD with a daily maximum flow of 1.525 MGD.  In 2016 the average daily flow was .526 MGD, which is discharged into the Oconto River.  The existing treatment facility uses trickling filters as its main treatment unit.   As the water enters the plant it enters and flows thru a fine mechanically cleaned bar screen and compactor, grit removal, clarigester, trickling filters, and a final clarifier with a solids contact unit.  Before the water enters the Oconto River it flows thru a seasonal (May 1st-September 31st) disinfection system.  This disinfection is achieved with the use of UV disinfection system.  Phosphorus treatment is accomplished with the aid of ferric chloride addition in the final clarifier.  Solids are treated in the anaerobic digestion unit of the clarigester.  Excess solids produced within the digester are pumped into the sludge storage tank, where they are then spread onto DNR approved agricultural lands.

Laboratory and Pretreatment Program

The treatment plant is equipped with a laboratory to perform the majority of the process control analytical testing.  Testing that is performed by the staff includes Biochemical Oxygen Demand (BOD), Total Suspended Solids (TSS), pH, Total Phosphorus, and Fecal Coliforms; which is required to meet our WPDES permit from the Wisconsin DNR.WASTEWATER OPERATOR

Maintaining your Pipes and the Cities Pipes

Fats, oils, and Grease (FOG) should never be poured down any drain, as they can cause clogged pipes, backups, and lead to costly repairs for both the homeowner and city owned sewer.  FOG materials can harden quickly once poured into the drain and cause a buildup in your pipes eventually leading to a clog and a backup.  All FOG materials should be disposed of in a trash can.

“Flushable” wipes are becoming an increasing problem within the sewer mains and causing backup events to occur.  These wipes should never be flushed even if the product label says “flushable”, and disposal should be in the trashcan.  Typical issues that “flushable” wipes cause is clogging of pumps and sewer main blockages.  These wipes do not breakdown once in the sewer system and they become balled up with other wipes and eventually they cause a blockage.  There are many common items found within the sewer system that should not be flushed.  These include, but are not limited to “flushable wipes”, baby wipes, paper towels, towelettes, cleaning wipes, feminine products, floss, clothing items, fishing line, plastic bags, and diapers.  All of these must be placed in the trashcan, not flushed.  The only things that should be flushed is human waste and toilet paper.

Meter Reading & Billing

Similar to reading your electric meter, Oconto Falls Municipal Utilities crew members collect usage data from your water meter with an automatic meter reading (AMR) device. Our data collection devices read your meter from a distance and store that information in a format that is then downloaded into our billing software to help produce your monthly billing statement. The usage from your water meter is then transfered into sewer data and you are billed based off of your water usage.

In some cases or during certain times of year when we are not able to get close enough to your meter, our data collection devices are not able to communicate with your meter to deliver consumption data. In that event, we provide you with an estimated billing statement, based on your normal usage history for that time of year. Any difference between the amount actually used and the estimated amount billed is corrected automatically when the next regular meter reading is obtained.  Ultimately, you pay only for the amount of sewer actually used.

During the summer months (on your August, September, and October 1st bills) our residential customers receive a seasonal sewer credit to account for the amount of water that does not enter our sewer system due to outside water use. Customers may also receive a pool fill credit if they inform the Utility office of the beginning and ending water reading after filling their pool. If you have questions on how this works, please contact the Utility office.

View our Residential, Commercial and Industrial Sewer Rates