Tri-State Field Conference 1980: Trip 4: Green Bay Metropolitan Wastewater Treatment Plant Tour

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay

Harold J. Day


This field trip will involve a tour of the Green Bay Metropolitan SewageTreatment Plant and a discussion of water quality in the Fox River and GreenBay. Improvements and maintenance of water quality requires wastewater treat- ment plants, reduction of non-point pollution, careful planning, and management of the system.

Good water quality has long been a concern of people in the Fox River Valley.Consistent with this concern, the Fox Valley Water Quality Planning Agency(FVWQPA) is developing a water quality plan to enhance and maintain the waterquality of the Fox River-Lake Winnebago watershed. The FVWQPA will firstevaluate the current situation. That assessment will then be used to developa water quality plan that is environmentally sound, economically feasible andsocially and politically acceptable to private enterprise, citizens andgovernments in the area.

The Fox Valley Water Quality Planning Agency

The FVWQPA was formed, through the cooperation of the Central WisconsinRegional Planning Commission and the Green Bay, Brown County Planning Commission,under section 208 of the Federal Water Pollution Control Act Amendments of 1972.That's why people sometimes refer to it as a "208 Agency." In response tolocal requests Governor Lucey designated the watershed for Areawide WasteTreatment Management Planning, and the U.S. Environmental Protection Agencyprovided $772,000 in funding to finance a two-year planning program as wellas during the ensuing years since 1977.

The Agency is governed by a board composed of 13 members, all elected local officials selected on the basis of population. Two advisory committees, the Technical Advisory Committee (TAG) and the Citizen's Advisory Committee (CAC),each composed of citizens chosen on the same basis as the Agency Board, workclosely with the Board on all aspects of the planning effort. In addition,an Areawide Planning Advisory Committee, with representatives from federal,state and local agencies, helps the agency coordinate its work with othergovernmental programs and authorities.

Local People Will Have Something To Say About This Plan

Local participation is necessary for the "208" program, both in developingtechnical and management alternatives, and selecting final recommendationsfrom fully detailed alternatives. For these reasons, the FVWQPA is activelyseeking to explain its work to the general public in the Fox Valley area.To obtain information about water quality problems and how they should be remedied, the Agency will be contacting individual citizens from time to time through Public Information Sessions. We'd like all concerned to attend these meetings and comment on the progress of our work.

In addition, formal review of the work of the Planning Agency will be continuously sought from local governmental units. When a final plan isdeveloped, it must again be submitted to each city and county government.The final plan must also be submitted to the Wisconsin DNR, the office ofthe Governor and the U.S. Environmental Protection Agency.

Not Just Another Study

The work of the FVWQPA is not just another study of the Fox River; rather,it is the first comprehensive effort to describe and remedy the impact ofthe many kinds of pollution in this watershed. Previous studies will beused if appropriate, but a considerable body of new information, particularlyrelating to what is called "non-point pollution," must be developed.

Non-point source pollution comes from other than a specific geographic pointor source. Examples would be the erosion from a half mile stretch of riverbank or the run-off from a heavily-developed urban area or a farm field.The impact of non-point pollution is especially difficult to assess becauseof the complexity of determining how much and what kind of material is gettinginto the water.

Point source pollution is the discharge from a single pipe or outfall. itenters the watershed at a particular point and thus can be measured andchecked for content quite easily.

Completion of this plan will give local governmental leaders their firstreal understanding of the current status of the total watershed so theywill be able to decide where to concentrate their efforts. The final planalso has to be expandable so later information on specific problems andnewer technologies can be incorporated into the overall management strategywithout making the current plan obsolete. indeed, part of the job now isto indicate areas where further work will be needed.

Management Planning-The Action Step

Results are what makes this work different from other studies of the FoxRiver and Lake Winnebago. Without action on what you've learned about thewatershed your effort is wasted.

The action part of this program comes with what is called management planning.The nuts and bolts of cleaning up the water, the implementing of the technicalsolutions developed is "management planning." When we say the plan will pro-pose a "management structure," we mean it will recommend the agencies to beresponsible for implementing the final 208 plan. This management structurewill most likely be made up of existing government agencies, but a newstructure might be suggested for a specific area or problem if one isneeded. The management structure also will include recommendations concerningthe legal authority and financial resources necessary for implementation andcontinued plan revisions, as needed.

Good management planning is essential for achieving maximum gain at theleast cost. In this case cost includes not only building and maintainingpollution control facilities but the costs accruing because the water ispolluted. Examples of such costs include, the increased expense of treatmentfor a municipal water supply or the costs incurred in terms of lost recreational potential.

Green Bay -Metropolitan Sewerage District Wastewater Treatment Facilities

One of the important treatment facilities on the Fox River is the Green Bayfacility. The following data and site plans are intended to help you understand what the Green Bay Metropolitan Sewerage District is doing to curbpollution.

The treatment plant is divided into three major areas of treatment. Thefirst stage is called Mechanical Treatment. The domestic waste enters thePumping Station about 70 feet underground. The sewage is then pumped tothe Headworks Building where large solids are removed by bar screens. Thesewage travels into primary settling basins where heavy solids settle to thebottom. These solids are called "sludge" and will be dealt with in thethird stage of treatment. The sewage then travels to the second stage.

Mill waste is also treated at the MSD facility. This waste originates fromAmerican Can and Procter & Gamble Paper Products Company. The waste comesindependently to the Pumping Station and is pumped directly to the secondstage for treatment.

The second stage of treatment is called biological treatment. In this stage,microscopic organisms ("bugs"), combined with sewage and air in the aerationbasins, assist in the removal of the organic pollutants from the wastewaterstream. After the bugs have done their work, the sewage travels to a finalsettling basin where the bugs or residual sludge are allowed to settle to thebottom. The now-treated water travels to a chlorine contact basin wherechlorine is added to destroy any disease-causing organisms. The treatedwater is then discharged into the Fox River. The bugs that have settled inthe final basin are called activated sludge and are pumped to a reaerationbasin where they again assist in removing the pollutants from the wastewater.The bugs that do not enter the aeration basin are pumped to the third stageof treatment called "Solids Processing."

In the Solids Processing phase, the return activated sludge is pumped to anair flotation thickener where the sludge is thickened by reducing the watercontent. The primary sludge is thickened by gravity in the gravity thickeners.The combined thickened sludges are pumped to thermal conditioning units-112-where the sludge is "cooked" under high temperature and high pressure tocause it to give up more of its entrapped water. The "cooked" sludge ispumped to vacuum filters where additional water is removed by the vacuumprocess. The sludge is then moved by conveyor to an incinerator where thesludge is burned, reducing it to ash. The ash is then transported to anapproved landfill. Gases generated in the incineration process are scrubbedso that the District will meet the most stringent air pollution standards.Heat is recovered from the incinerators and used for plant heating.

Major Equipment And Suppliers  

Location and/or Item Number Physical Size or Unit Capacity Manufacturer
Pump Station
2 Coarse bar screens 8' wide Link-Belt
4 GBMSD pumps 40 mgd (900 hp) Allis-Chalmers
3 Mill Pumps 11 mgd (150 hp) Allis-Chalmers
Basin Complex
2 fine bar screens grit removal equip. 8.75' wide Dorr-Oliver
4 Hydroclones 290 gpm Dorr-Oliver
2 Classifiers   Dorr-Oliver
 4 Primary basins 120' sq x 12' SWD Dorr-Oliver
 4 Contact aeration basins 73' x 244' x 20 SWD  
12 Aerators per basin 125 hp Mixing Equipment Co
4 Rearation basins 36' x 244' x 22' SWD  
6 Aerators per basin 75 hp Mixing Equipment Co
8 Final basins 125' sw x 14' SWD Dorr-Oliver
2 Chlorine contact basins 40' x 113' x 12' SWD  
W/2 Rapid mixers 10 hp Mixco
4 Process Air Compressors +55,000 scfm-2,500 hp Brown Boveri
Flotation Thickener Building
8 Thickener basins 20' Dia x 95' x 11' SWD Envirex
Gravity Thickener Complex    
2 Thickener basins 45' Dia x 10' SWD Dorr-Oliver
Solids Processing Building
 4 Thermal Conditioning systerns 150 gpm Zimpro
6 Grinders 150 gpm Robbins & Meyers
8 High pressure pumps 150 gpm  Zimpro
4 Air Compressors 315 scfm Cooper Panjax
Instrumentation   Honeywell
4 Vacuum filters 12' Dia x 16' long Envirotech
Incineration Systems 14 T/hr    
2 Furnaces 22' Dia x 7 Hth Envirotech
3 ID fans  250 hp Zurn Ind. 
2 Scrubbers   Arco
Instrumentation   Honeywell
2 Scum thickeners 35 gpm Envirotech
2 Process boilers 16,000 lb/hr. Cleaver Brooks
2 Heating Boilers 31,600,000 btu/hr. Cleaver Brooks
1 Waste heat boiler 32,000 lb/hr. Deltac
1 Deodorizing Burner 1.700 to 4.000 scfm Surface Combustion
Chlorine Feed System
16 Chlorinators 2,000-8,000# cap. Wallace & Tiernan
4 Automatic residual analyzers   Wallace & Tiernan
8 Evaporators  8,000# capacity ea. Wallace & Tiernan
26 Points of Injection   Wallace & Tiernan
Other Chemical Feed Systems 
Alum Ferric system 8.75 gpm BIF
polymer-liquid and dry 0.92 gpm BIF
Phosphoric acid 13 gpm BIF
Caustic soda 26 gpm BIF
Nitric acid   BIF
Decant & Equalization Basin Area    
2 Decant basins 60' Dia x 12' SWD Dorr-Oliver
2 Equalization Basins    60'Dia x 14' SWD  Dorr-Oliver
Miscellaneous Computer & general Instrumentation Fischer & Porter
Other Interesting Facts: Material used In construction
Concrete 90,000 Cu Yd Backfill: 133,000 Cu Yd
Rebar 7,000 Ton Electrical Conduit: 84 miles
Excavation 334,000 Cu Yd Electrical Wire: 338 miles

Return to Professor Dutch's Home Page

Created 30 August 2004, Last Update 20 January 2020

Not an Official UW-Green Bay site