A new WOTUS rule has been released. These new definitions replace the 2015 Obama era rule. Many agriculture organizations are celebrating the new rule. Photo of the Chippewa River (Minn.) by Andrea Johnson.

ST. PAUL, Minn. – Last month, the Environmental Protection Agency (EPA) and the Department of the Army finalized a new Waters of the U.S. (WOTUS) rule. The new WOTUS rule replaces the 2015 rule and is intended to clarify what waters are and are not covered by the Clean Water Act.

“Waters of the U.S. has a long history of definitional changes over decades of Clean Water Act implementation,” said Melissa Kuskie, manager of the certifications, environmental review and rules section for the Minnesota Pollution Control Agency (MPCA). “What was just finalized was another update to the definition of Waters of the U.S.”

The definitions laid out by WOTUS are important because they are the rules used by the EPA to enforce the Clean Water Act.

The new WOTUS rule was signed on Jan. 23, 2020, and will take effect 60 days after it is published in the Federal Register. Prior to approval, state agencies, including the MPCA and the Minnesota Department of Natural Resources (DNR), were able to weigh in on the rule and send comments to the federal level.

One main concern was lack of scientific validity behind the approach, particularly on using flow instead of connectivity to define a tributary. The MPCA and DNR explained several concerns in a comment letter submitted in April 2019.

“What was recently finalized definitively removed waters like ephemeral streams from WOTUS. Ephemeral streams are streams and features that only tend to flow when there are significant rain events,” Kuskie said.

Also excluded from this WOTUS rule are isolated wetlands. These would be waters that have no direct connection to a stream, river or other body of water.

“Previously, the answer as to whether those bodies were or were not WOTUS would for the most part be ‘it depends’ and that is certainly a complicated answer,” she said.

The new rule also states that groundwater is not WOTUS.

“Now, groundwater had not typically or traditionally been considered WOTUS, but there have been court cases over the past few years of attempts to assert a connection,” she said. “This rule explicitly says groundwater is not WOTUS.”

Another change to WOTUS was the addition of a ditches category or definition. In the previous rule, ditches were not defined. Now they are defined as artificial channels used to convey water and are not jurisdictional unless they are made adject to another body of water.

An important thing to note for agriculture is that the exemptions to WOTUS have not been changed.

“WOTUS has long had exemptions for different types of agricultural land or prior converted crop lands. Things like that had always been excluded from the definition of Waters of the U.S., and that hasn't changed,” she said.

Artificial lakes and ponds that have been constructed upland remain excluded. This can refer to water storage reservoirs or livestock watering ponds.

While the new WOTUS rule is being celebrated among national agriculture organizations, the new rule will not have a significant impact on how waters are defined and regulated in Minnesota.

Individual states can set their own regulations to define Waters of the State and regulate those as they see fit.

“It's Minnesota statute 115.01 subdivision 22, and it says that Waters of the State are defined as all streams, lakes, ponds, marshes, watercourses, waterways, wells, springs, reservoirs, aquifers, irrigation systems, drainage systems, and all other bodies or accumulations of water, surface or underground, natural or artificial, public or private, which are contained within, flow through or border upon state or any portion thereof,” Kuskie said.

Minnesota’s definition of waters is designed to be broad and cover more bodies of water, but that does not mean the MPCA is enacting control over every body of water.

The MPCA is most particular about water quality standards. Setting use and limitations on water bodies based on their quality and working to either improve or maintain quality.

For Minnesota’s agriculture industry, the new rule does not change much. Farmers are not going to see any increased regulation due to the new definition and can continue with business as usual.