OLIVIA — Southern Minnesota Beet Sugar Cooperative will be allowed to discharge its treated wastewater into Renville County Ditch 45 during April as part of a compromise agreement reached Tuesday.
The Renville County Board of Commissioners, acting as the Drainage Authority, approved the extension of the September-to-March drainage period into April with conditions proposed by the cooperative.
Downstream landowners have opposed an extension of the discharge period into April due to concerns that it could adversely affect field drainage during a critical time for planting.
The approved conditions will require that the cooperative immediately stop its discharges if the level of water in the ditch at two culvert locations — 242nd Street and County Road 6 — exceed specified trigger points during April discharges.
At the upstream culvert, 242nd Street, the trigger point is an elevation of 1,052.4 above sea level, which is 1.5 feet below the ditch freeboard level. At that elevation, the flow is 25% of capacity at the location, according to information provided by engineer Paul Swenson with Barr Engineering. The trigger point at County Road 6 is an elevation of 1,049.8.
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The agreement requires that the cooperative clearly mark the elevation levels at the two culvert sites so that the flow levels can be observed by the public. The company will monitor the elevations on a daily basis. It will also look at making the data available on its website or in some other manner available to the public.
The proposed trigger points are designed to assure that flows from the cooperative do not adversely affect the efficiency of private, farmland drainage systems flowing into the ditch.
“We heard the farmers’ feedback,” said Sagar Sunkavalli, environmental director with Southern Minnesota Beet Sugar Cooperative, when introducing the compromise proposal.
Farmers had unanimously voiced opposition to the April discharges at a hearing held March 22. Concerns remain, but the compromise also found support with some landowners.
Landowner Mark Chan said the limitations were acceptable to him as they addressed his concerns about field drainage.
Yet others still expressed concerns.
Joel Bakker said that he remains concerned about the potential to slow field drainage. He said that engineers are not basing their calculations on real-time observations of the fields as he and other landowners do.
Don Buesing, who farms a low area on the system, said he is worried that the ditch is being undercut and that wintertime discharges from the cooperative play a role.
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“We look at it and think they are wearing our ditch out,” he told the commissioners.
The commissioners approved the new agreement on a 3-1 vote, with member David Hamre opposed and members Greg Snow, Doug Erickson and Randy Kramer approving it.
“I feel the beet plant is trying to do right here,” said Snow, who introduced the motion to approve the agreement.
Commissioner Bob Fox was not present at the meeting. At the March 22 meeting, he had voiced concerns about an April extension.
Studies by Barr Engineering for the cooperative and by Bolton & Menk Engineering both concluded that the ditch had capacity to handle April discharges without adversely affecting field drainage, provided there were restrictions during certain flow periods.
Last month, engineer Shaun Luker with Bolton & Menk had concluded that “care should be taken” in allowing the additional discharge based on the 3.6 million gallons-per-day maximum as allowed by the co-op’s discharge permit. He said his review of the most recent proposal led him to believe it represents a good compromise and should not adversely affect field drainage.
Based on a study of precipitation records in the watershed, it’s calculated that the cooperative will be able to discharge 90% of the time in April within the new parameters. It will be assessed a higher percentage of benefits for the system as a result of the extended discharge period.
The sugar cooperative is seeking the additional discharge time to help reduce the volume of water that must be stored on ponds on the factory site in Renville. Sugar processing continues through April.
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This debate over April discharges is the result of action last year by the Minnesota Pollution Control Agency to approve a new discharge permit for Southern Minnesota Beet Sugar Cooperative. It allowed the co-op to increase its daily discharge into County Ditch 45 from 2.3 million gallons to 3.6 million gallons per day from Sept. 1 through April 30.
The discharges in April must stop if the waters in Sacred Heart Creek warm to 55 degrees Fahrenheit since it would disrupt fish spawning.
However, the MPCA permit gives final authority to the Renville County Drainage Authority. In July, the commissioners approved the increase in daily discharges to 3.6 million gallons but they had limited discharges to the period of Sept. 1 through March 31.
