Recycling Treated Municipal Wastewater for Industrial Water Use

Section 3
Inventory of Major WWTPs and Potential Industrial Reuse Demands
Craddock Consulting Engineers 3-41
In Association with CDM & James Crook
WWReuseTM1_Sec 3_final.doc
Factors Influencing Potential for Industrial Reuse
The Western Lake Superior watershed has similar water availability indices as
described for the Rainy River watershed. The northern half is in Area 6 and the south
half is in Area 4. Both of these areas have limited bedrock aquifers. The north half has
limited water supplies in all three aquifer zones, while the south half has productive
surifical aquifers and less productive buried sand aquifers. The north half of the
watershed is the least prone to ground water contamination, while the south half has
some pockets of medium to highest susceptibility of contamination.
Limitations on pollutant discharges will continue to be a focus for this watershed.
This region of Minnesota is a treasured recreation area and also provides resources for
the state’s mining and forest industries. The Lake Superior Basin Plan, completed in
2004, provides recommendations for policy and initiatives to enhance and protect this
watershed and the industries that contribute to the economic vitality of the area. The
partnerships and mandates associated with the Great Lakes Water Quality Agreement
and related programs are expected to continue to influence the management of the
watershed in response to the region’s growth. One example is the Zero Discharge
Demonstration Program, which is devoted to the goal of zero discharge of nine
persistent bioaccumulative toxic substances.
3.3 Metro Area Inventory
The range of industries in the Minneapolis/St. Paul metro area provides a perspective
on the full range of industries that can be present in a community. Unlike the analysis
of industrial demands outside the metro area, the inventory for the metro area
includes industries that use a municipal potable supply and/or withdraw from
ground or surface waters at lower thresholds than required for an appropriations
permit (1 mgy or 100,000 gpd). The Met Council monitors all industries that discharge
to the metro area regional sewer system. The database for the industrial users
permitted by the Met Council was used to identify the industry, the type of industry,
the facility location, and the amount of water that enters the facility. Some industrial
users may consume most of this supply and others may discharge all of it to the sewer
system. The water use data evaluated for this project is the industrial water demand –
what comes into a facility.
Metro Area Overview
The industrial customer inventory for the metro area is represented by a diversity of
industries and a prevalence of potential industrial reuse customers along the river
corridors. Figure 3.18 presents the industries with water permits (MDNR
appropriation permits) and Figure 3.19a locates the larger set of industries in the
metro area, represented by the Met Council’s Industrial User permit program.