Return to homepage of -- 'General Mills vs Minnesota DNR' --

Below is posted the Feb. 2000 update from DNR Waters on once-through cooling systems. ----- ds

Once-Through System Update
DNR Waters, February 2000

In 1988, there were approximately 125 water appropriation permits for office buildings and other types of structures that used ground water for heating and air-conditioning purposes. These “once-through systems” pump water through the heating, ventilation or air conditioning (HVAC) equipment and then discharge the water without recirculating or reusing the water for another purpose. In 1989, 11 billion gallons of ground water was used for once-through systems and accounted for 19% of the total ground water use in Hennepin and Ramsey Counties.

The 1989 Legislature determined once-through systems were not the best or most efficient use of Minnesota’s valuable ground water resources and passed legislation (M.S. 1030.271, Subd. 5) prohibiting new permits for once-through systems. The 1990 Legislature required existing systems to be phased out to protect water supplies for future higher priority uses. Once-through systems pay $200 per million gallons in annual water use fees (versus a maximum of $4.50 per million for other users) and systems must convert to water efficient HVAC alternatives at the end of the design life for the equipment, but no later than the year 2010.


Systems Converted: 74

Systems Scheduled to Convert between 2000-2010: 30

Conversion Not Required (<5 million gallons per year): 30

Exemption from Conversion Requirement (M.S. 103G.271, Subd.5, Para.C, Item 4): This exemption was sought by H.B. Fuller in 1992 and requires applicants to spend double the cost of conversion on development of a nature preserve. General Mills is seeking an exemption under this section and has filed a law suit against the DNR rather than requesting a permit amendment.


1989 --- 11.06 billion gallons
1990 ---- 8.34 billion gallons
1991 ---- 8.44 billion gallons
1992 ---- 6.32 billion gallons
1993 ---- 7.09 billion gallons
1994 ---- 7.67 billion gallons
1995 ---- 6.22 billion gallons
1996 ---- 5.32 billion gallons
1997 ---- 5.03 billion gallons
1998 ---- 5.27 billion gallons

Additional Information Contact: DNR Waters Director Kent Lokkesmoe (651) 296-4810 or Water Appropriation Permit Program Manager Jim Japs (651) 297-2835

website by dave stack , --- last update 00nov18