Everybody Wins at Ho-Chunk Casino in Wisconsin

Meeting nutrient removal requirements at widely varying biological loads

At the Ho-Chunk Casino owned and operated by the Ho-Chunk Indian Tribe, thousands of people try their luck. However, at the wastewater treatment facility, customers, suppliers, and engineers win.

Challenge

Due to the increase in tourism and the development of residential communities, the Ho-Chunk Nation Indian Tribe realized they would need to install a new wastewater treatment facility to meet future and current requirements.  Also, with the strength of waste almost three times above the norm for domestic waste streams the existing system was in jeopardy of failure.

 

Solution

With the need for nutrient removal and the requirement to handle widely varying biological loads, the OMNIFLO® Sequencing Batch Reactor (SBR) process was the logical choice.  Additionally, the OMNIFLO SBR process was a beneficial option because of its ability to be operated remotely via a computer SCADA system, thus reducing on-site staffing for operation. 

The design can handle a wide range of loadings, and achieve nitrification, denitrification and biological phosphorous removal.  This is critical in this application since the wastewater is high in BOD and total nitrogen.

" We were pleased that the project went so smoothly. Even though we made some changes along the way, the design build concept was very effective. "

Carol Rollins, Ho-Chunk Nation’s Environmental Health Services Department Black River Falls, WI

Results

The original two-tank OMNIFLO SBR was designed to treat 150,000 gallons-per-day (gpd). In the year 2000 the facility was upgraded by adding two more SBR tanks, which increased their treatment capacity to 300,000 gpd. The treatment process begins with the influent wastewater being pumped from the Ho-Chunk Nation Casino to the OMNIFLO SBR facility. The system includes an influent holding tank, SBR tanks equipped with jet aeration, and a sludge holding tank fitted with coarse bubble diffusers. In the SBR, equalization, aeration, clarification, and decanting occur in a timed sequence. By varying the operational strategy, aerobic, anaerobic, and anoxic conditions can be achieved. The design can handle a wide range of loadings and achieve nitrification, denitrification, and biological phosphorus removal. This is critical in this application since the wastewater is high in biochemical oxygen demand (BOD) and total nitrogen.

The project moved from concept to completion in six months with start-up of the facility in March 1998.  Since then the facility was expanded which more than doubled their treatment capacity.

 

Over 35 Years and 700 Installations & Counting

​Evoqua's SBR systems with Jet Tech technology have helped municipalities and industries overcome wastewater challenges for over 35 years across 700 successful installations. Today, Evoqua's SBR systems are successfully treating wastewater in plants ranging from 0.01 MGD to 60 MGD. Evoqua's product experts provide process knowledge and expertise to deliver SBR systems that provide superior consistent performance, flexible design and simple operation under the most demanding wastewater treatment conditions.