Recycling Treated Municipal Wastewater for Industrial Water Use

Section 2: Recycled Wastewater Demand & Supply
Recycling Treated Municipal Wastewater for Industrial Water Use
Factors Influencing Potential for Industrial Use of Recycled Wastewater
The availability of higher quality ground water, typically sought first for municipal and industrial
purposes, is a key factor in planning for growth in most of Minnesota. The summary of watershed
inventories presented in Table 2.11 includes the assessment of indicators favoring recycled wastewater
applications. This high level assessment indicates several areas of the state with limited ground water
supplies. These areas are in the Des Moines River and Missouri River watersheds, in the southwest part of
the state, northwestern Minnesota in parts of the Red River of the North watershed, and in the Rainy
River and Western Lake Superior watersheds, in north central and northeastern Minnesota. The water
requirements for ethanol facilities in the southwest part of the state have prompted agencies and industries
to work together to meet immediate water demands while protecting the aquifer supplies for long-term
use.
There are also community-specific water supply limitations in quality and quantity. Ground water
contamination is found throughout the state and certain aquifer characteristics make some aquifers a less
reliable supply, as in the karst area of the Lower Mississippi River watershed. In general, the water
quality of an area and susceptibility to contamination must be assessed on a site specific basis.
Community-level planning has usually been used to assess water supply needs in Minnesota. Planning has
moved to the watershed level as observed in the state’s water-limited areas of the Des Moines River,
Missouri River, and Red River watersheds. Water supply planning, including identification of future
water supply limitations, has encompassed a regional scale in the 7-county Twin Cities metro area, as
directed under Minnesota Statutes, Section 473.1565.
As the state moves forward with TMDL development and new WWTPs or existing ones are expanded,
evaluations of wastewater recycling facilities to reduce pollutant discharges are expected to become more
prevalent. However, municipalities will not be able to recycle without partners – industries and other
wastewater recycle customers need to commit to meeting their water demands with this alternative
supply. As observed in the expansion of the ethanol industry and the construction of the Mankato Energy
Center – a limited water supply was the key factor that led to consideration of a recycled wastewater
supply. While other drivers may lead to wastewater recycling partnerships between municipalities and
industries, the most significant driver in the near-term is expected to be water supply limitations,
principally ground water supplies limited by quantity or quality issues.
34 Metropolitan Council Environmental Services