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Groundwater analysis finds aquifers strong in Park Rapids, Pineland Sands

| Posted in: Land Sustainability & Stewardship

For nearly 60 years, R.D. Offutt Farms (RDO) has farmed in Central Minnesota’s sandy soils. These soils are ideal to grow potatoes and are well suited for irrigation to sustain crops in between rainfalls. As stewards of natural resources, we wanted to look at groundwater conditions following the drought year of 2021.

What is an aquifer?

An aquifer is a collection of wet, underground rocks that allows water to pass through it slowly. A well can be used to pump water from an aquifer so people can use the water for drinking, watering crops, and other purposes. Natural groundwater recharge occurs as precipitation falls on the land surface, infiltrates into soils, and moves through pore spaces down to the water table. In Minnesota, groundwater supplies 75 percent of the state’s drinking water and 90 percent of agricultural irrigation needs. Source: Minnesota Department of Natural Resources.

In June 2023, R.D. Offutt Farms hired Foth Infrastructure & Environment, LLC., to conduct an independent study to review groundwater levels and changes over time within a 10-mile radius in the Pineland Sands region.

The Pineland Sands area aquifers are critical in supporting the Park Rapids area. Aquifers are used for drinking water, domestic, industrial, recreational uses and agricultural irrigation.

Methodology

The groundwater analysis was conducted using publicly available data through the Minnesota Department of Natural Resources Cooperative Groundwater Monitoring Program. The focus of the study was data from 31 groundwater wells whose water levels have been continuously measured since the mid-1980s (and in many cases, the 1970s) and are still being measured today. RDO cooperates with the DNR to host groundwater monitoring wells throughout our farming operation; the agency collects the data as part of the monitoring network.

To provide an understanding of groundwater levels, the Foth study examined minimum, maximum, average, and standard deviation water levels over the course of 2022 and over the entirety of the well's recorded records. Many of these wells have had continuous monitoring instrumentation installed in them and have been reporting hourly data during the last five years.

Average yearly water level trends show little variation over decades of monitoring. Source: Foth Infrastructure & Environment, LLC.

Findings

Over the last several decades, water use in the Pineland Sands region has risen as the number of water appropriation permits issued by the Minnesota Department of Natural Resources (DNR) has steadily increased. This is in addition to non-permit users who may withdraw up to 10,000 gallons per day without needing a permit.

Key findings from the study included:

  • The data shows that groundwater levels have generally remained stable in the five-decade record that was analyzed, demonstrating that the groundwater system is resilient and water withdrawals for use are apparently balanced by replenishment through recharge from precipitation and connected surface water resources.
  • The study calls attention to data from 2022, a “key year” defined after historic drought conditions the year prior in the Pineland Sands region. Notably, the 2022 data is “broadly similar” to that from the 1970s and 1980s.
  • This qualitative assessment shows that impacts related to groundwater withdrawals within the area of review are temporary, and annual water levels rebound to average conditions following seasonal agricultural irrigation.
  • The Pineland Sands area is highly monitored and given the robust nature of the available dataset, decreasing groundwater levels should show up if they are occurring.

"We want to preserve water resources for generations to come.”

Warren Warmbold
Warren Warmbold, Vice President of Operations at R.D. Offutt Farms

Warren Warmbold, Vice President of Operations at R.D. Offutt Farms, grew up in Park Rapids and has lived in the area nearly his entire life. He said the report findings ring true to what he’s witnessed during his 45-year farming career, and that the seasonality of the Midwest is helpful to support agriculture.

“Unlike other parts of the country, farmers in Minnesota only irrigate as needed for about five months of the year – typically between May and September,” Warmbold said. “During the rest of the year, snow and rain saturate the ground in preparation for the next growing season.”

Warmbold went on to say that even with a naturally replenishing groundwater system, RDO understands the importance of water conservation.

“In the absence of rainfall, we rely on irrigation to sustain our crop … but we only give it the exact amount of water it needs, and not a drop more,” Warmbold said. “We want to preserve water resources for generations to come.”

To read the Foth analysis, click here: White Paper - Analysis of the Groundwater Levels around Park Rapids

To look at individual monitoring wells and associated data, click here: Cooperative Groundwater Monitoring