Recycling Treated Municipal Wastewater for Industrial Water Use

Section 2: Recycled Wastewater Demand & Supply
Recycling Treated Municipal Wastewater for Industrial Water Use
Treated Wastewater Supply – Lower Mississippi River Watershed
There are 12 municipal WWTPs in the Lower Mississippi River watershed with design capacities greater
than 1 mgd. Table 2.5 summarizes the design capacity and historic flows for the plants. There are three
facilities within 70% of the design capacity: Owatonna, Plainview-Elgin, and Rochester. Rochester is
nearing completion of construction for an expansion to 24 mgd. In 2005, approximately 40 mgd of treated
wastewater was discharged into the Lower Mississippi River watershed from these 12 facilities. Smaller
WWTPs account for 16% of the combined capacity of WWTPs discharging to surface waters in the
Lower Mississippi River watershed. This would equate to an annual average flow of 15 mgd if these rural
communities grew to use the full capacity of their WWTPs.
Table 2.5. Larger WWTPs in the Lower Mississippi River Watershed
Facility Name
Permitted
Capacity,
mgd
2005 Annual
Average Flow,
mgd
Flow as % of
Design Capacity
Faribault WWTP 7.0 3.7 53%
Lake City WWTP 1.5 0.6 37%
Met Council - Empire WWTP* 24.0 8.5 35%
Met Council - Rosemount WWTP* 1.3 0.9 70%
Northfield WWTP 5.2 2.1 40%
Owatonna WWTP 5.0 3.5 71%
Plainview-Elgin Sanitary District WWTP 1.4 1.1 74%
Red Wing WWTP 4.0 2.1 51%
Rochester Water Reclamation Plant 19.1 13.5 71%
Stewartville WWTP 1.1 0.5 48%
Whitewater River Regional WWTP 1.1 0.7 63%
Winona WWTP 6.5 4.0 61%
Total 77 41 53%
*The Rosemount WWTP is located in the Lower Mississippi River Watershed, but discharges into the Mississippi River-
Headwaters watershed. In late 2007 the Empire WWTP will move its discharge near the Rosemount WWTP discharge and
the Rosemount WWTP will be phased out. The Empire WWTP and Rosemount WWTP design capacities are used, instead
of permitted capacities.
Source: MPCA, 2005
Proximity of Industries Relative to WWTPs – Lower Mississippi River Watershed
A total of 56 industries are permitted to withdraw ground and/or surface water in the Lower Mississippi
River watershed and 25 of these are located within 4 miles of a larger municipal WWTP. Figure 2.12
presents the location of the industries and WWTPs in the Lower Mississippi River watershed. Table 2.6
summarizes the industries within a 4-mile radius of a WWTP. Appendix II-1 (Appendix C) provides the
full industry list.
Winona has the largest number of industries in close proximity to its WWTP. Water is used for metal
processing by Badger Foundry Company and Peerless Chain Company, non-metallic processing by RTP
Company, industrial process cooling by Cytec Engineered Materials, and agricultural processing by
International Malting Company. Red Wing and Faribault are two other cities with multiple industries
within the proximity of their WWTP.
There are several agricultural processing facilities within 4 miles of a WWTP. The larger agricultural
processing water users are Associated Milk Producers (2.7 mgd) near the Rochester Water Reclamation
Plant, International Malting Co. (1 mgd) in the Winona area, and Marigold Foods (0.3 mgd) near the Met
Council’s Empire WWTP.
Metropolitan Council Environmental Services 21