There are a number of reasons why the rule focuses on agricultural areas and not urban areas. First, only a small percentage of the nitrogen fertilizer sold in Minnesota is applied to lawns, golf courses and parks. The MDA estimates that 94 – 95% of the nitrogen sold is applied to agricultural crops. The rate of nitrogen application to lawns is only 25% of the rates normally used on corn and other high nitrogen using crops. Second, the fact that nitrate leaching from fertilizer applied to lawns can range from low to very low. Lawns are perennial and have a dense root structure, so nitrate leaching losses are very similar to agricultural perennial crops and native prairie. Third, most of the concerns related to lawns are related to phosphorus rather than nitrogen. Unneeded phosphorus inputs were drastically reduced (80 – 85%) when the MN Phosphorus Lawn Fertilizer Law was passed in 2005. As part of that law, it is illegal to apply any fertilizer on impervious surfaces. The Phosphorus Lawn Fertilizer Law greatly reduces the risk of nitrogen entering storm water and other surface water bodies.
Public water supply wells are monitored for water quality under the Safe Drinking Water Act administered by the Minnesota Department of Health (MDH). This data is used by the MDA and MDH to evaluate nitrate levels and water quality trends. The MDA may also install a local groundwater monitoring network in a Drinking Water Supply Management Area (DWSMA).
Public water supply wells are monitored for water quality under the Safe Drinking Water Act administered by the Minnesota Department of Health (MDH). This data is used by the MDA and MDH to evaluate nitrate levels and water quality trends. The MDA may also install a local groundwater monitoring network in a Drinking Water Supply Management Area (DWSMA).
The purpose of the rule is to minimize potential sources of nitrate pollution in the state’s groundwater and to protect our drinking water. The rule is one tool, for specific situations, that is part of a larger strategy to reduce nitrate from fertilizer in groundwater.
The purpose of the rule is to minimize potential sources of nitrate pollution in the state’s groundwater and to protect our drinking water. The rule is one tool, for specific situations, that is part of a larger strategy to reduce nitrate from fertilizer in groundwater.
The authority for the rule comes from the Minnesota Groundwater Protection Act, Minnesota Statute 103H. The MDA has the authority to issue administrative, civil, and criminal penalties against those who violate the rule under Minnesota Statute 18D.
The authority for the rule comes from the Minnesota Groundwater Protection Act, Minnesota Statute 103H. The MDA has the authority to issue administrative, civil, and criminal penalties against those who violate the rule under Minnesota Statute 18D.
The MDA held informal and formal comment periods, 17 listening sessions across the state and received more than 800 written comments. The Groundwater Protection Rule became law in June, 2019. Application restrictions are posted on the MDA’s website by January 15 each year and the fall application restrictions begin September 1. See question 11 below for more detail on the fall and frozen soil restrictions.
The MDA held informal and formal comment periods, 17 listening sessions across the state and received more than 800 written comments. The Groundwater Protection Rule became law in June, 2019. Application restrictions are posted on the MDA’s website by January 15 each year and the fall application restrictions begin September 1. See question 11 below for more detail on the fall and frozen soil restrictions.
There are two parts to the rule. Each part contains separate provisions. Depending on where you farm, you may be subject to one part of the rule, both parts, or neither part.
Part 1: You are subject to Part 1 of the rule if you farm in a vulnerable groundwater area or in a Drinking Water Supply Management Area (DWSMA) that has 5.4 mg/L or higher of nitrate. This means you cannot apply nitrogen fertilizer in the fall and on frozen soils in those areas.
Part 2: You are subject to Part 2 of the rule if you farm land in a DWSMA with elevated groundwater nitrate concentrations. These areas will be designated a mitigation level 1, 2, 3 or 4.
