Groundwater springs are the lifeblood of our trout streams.  Trout depend upon a steady supply of cold groundwater to keep streams cool enough in summer, and warm enough in winter.  Whether large springs or small seeps, every trout stream relies upon vital inputs of groundwater.

In recent decades the rising demand for permits to remove groundwater from our aquifers has outstripped the finite supply.  Once viewed as limitless, and still mistakenly viewed this way by some, many aquifers are being depleted by excessive and unsustainable pumping.  As aquifer levels drop, the volume of natural springs entering trout streams begins to decrease.  Where unsustainable pumping continues, eventually too little groundwater remains in the aquifers to supply trout streams with the minimal base flow required to support trout and other aquatic life.  For this reason, wild trout are a good indicator of the health and sustainability of our groundwater systems.  Trout are recognized by informed individuals as finny versions of “canaries in a coal mine”, which can warn us of dangerous changes occurring underground.  Minnesota Trout Unlimited continues to fight back threats to sustainable use of groundwater.

In addition to groundwater quantity, pollution of groundwater quality can damage trout, aquatic insects and other aquatic life, not to mention human health.  Elevated levels of nitrate are of particular concern.  Trout streams, because they are so closely tied to groundwater are protected by the same federal drinking water standard of 10 milligrams per liter (10 mg/l).  The Minnesota Pollution Control Agency is still working to develop a water quality standard protective of aquatic life in streams and lakes, but scientific studies suggest that a chronic value (4 day duration) of less than 5 mg/L nitrate is needed for protection of aquatic life in coldwater (trout) streams and lakes.

Sustainable Use of Groundwater

Applications for DNR groundwater appropriation permits allowing pumping of huge volumes for irrigation have soared in the past 10 years and use is exceeding sustainability thresholds in some areas.  Some of these aquifers support valuable fisheries, such as the Straight River.  Groundwater is a public resource which landowners may make “reasonable use” of.  The amount which constitutes a reasonable use amount is set by statute and amounts above this require a permit from DNR.  State law requires DNR to permit only amounts which are sustainable and which do not deplete the aquifer or negatively impacts connected aquatic systems such as trout streams.

Legislative proposals to undermine sustainable management of finite groundwater supplies have returned in the 2018 legislative session.  As of April 24, 2018 these problematic proposals are included in the House Omnibus Environment Bill, HF 3502.

HF 3502 would:

  • Require DNR, rather than the applicant, to pay for a test well needed to determine if the high volume sought is sustainable (section 40)
  • Prohibit DNR from imposing conditions or requiring testing when a landowner transfers his/her permit to a new owner, even where the old permitted amount is no longer sustainable (section 39)
  • Require DNR demonstrate that any data used to restrict water usage “supports or verifies the decision”; existing law already requires decisions based on data and DNR does share data with applicants, but this add raise the bar, burden and costs (section 41)
  • Require DNR to conduct expensive economic impact studies for each permit application, even though it has no economists on staff and the central issue – is there is or is not enough water available – is factual, not economic (section 41)

MNTU opposes these attempts to curtail the sustainability standard for the use of groundwater.  The provisions are found in sections 39 to 41 of HF 3502 (lines 43.8 to 43.28).  Use the link below:

Groundwater Protection Rule – Nitrogen Fertilizer

Attack on Groundwater Protection ActApril 16, 2018

Bills to block adoption of a nitrogen fertilizer rule by the MN Department of Agriculture were heard in the House and Senate on Monday April 16.  For background on the proposed rule read our April 16 blog HERE.

April 24, 2018 Update:

The provisions blocking adoption of the rule are currently in at least three House bills and two Senate bills:

HF 2887;

HF 3719, section 13;

HF 4133, section 34;

SF 2893, Art 2, sec 16;

SF 3536, section 31;

Governor Mark Dayton has indicated he will veto these provisions.

Read Governor Dayton’s letter to the House Agriculture committee chairs HERE

Read the letter from MDA Commissioner David Frederickson to Senate leaders HERE

Read letter of MNTU and partners to House HERE

Read letter of MNTU and partners to Senate HERE

The Rule and map of vulnerable areas:

The proposed nitrogen fertilizer rule and a wealth of information on the draft rule can now be found on the Minnesota Department of Agriculture’s website at:

The MDA map of vulnerable areas dramatically illustrates why Trout Unlimited should be concerned about this issue: