The Des Moines Water Works (DMWW) filed its latest legal response on Friday, May 5claiming Iowa Drainage Districts do not have an agricultural stormwater runoff exemption for water discharged from drainage tiles. The Clean Water Act (CWA), however, is specific and makes it clear runoff water from agricultural fields is not a point source under the CWA and requires no federal NPDES permit.

Related: Des Moines Water Works files lawsuit

The 66-page opposition brief states “…there can be no regulatory basis for concluding that all agricultural drainage is nonpoint.” DMWW argues that agricultural stormwater drainage that is collected and channeled by the drainage districts are point sources, not nonpoint sources under the CWA.

The Iowa drainage districts, in their brief, have demonstrated clearly that agricultural drainage is a nonpoint source.

DMWW appears to lack understanding of agriculture and nonpoint source pollution (NSP). In fact, it says in its brief that even EPA seems to be “confused” on what is NSP.

EPA declares “NPS pollution is caused by diffuse sources that are not regulated as point sources and normally is associated with agricultural, silvacultural and urban runoff, runoff from construction activities, etc…”

Pretty simple!

DMWW’s main argument is the agricultural stormwater runoff exclusion does not apply to drainage districts with tiles. It spends pages arguing the CWA’s core command is to prohibit discharges of pollutants from point sources. It claims there has been inaction by EPA and the State of Iowa for 40 years.

DMWW further claims that by not regulating drainage district tiles there will be open neglect of public health and safe clean water. It claims “…regulatory inaction does not change the statutory landscape. The time has come to address pollution from drainage and to apply the ‘core command’ of the CWA to the drainage districts as the statute dictates.”

The only problem with this expansive statement is that it is wrong. Congress and the courts have made it clear nonpoint source runoff pollution from agriculture is exempt from the CWA’s regulation of point sources. EPA, on its webpage, describing what is a nonpoint source, declares “Nonpoint source pollution generally results from land runoff, precipitation, atmospheric deposition, drainage, seepage or hydrologic modification.”(It appears DMWW lawyers do not understand the terms drainage, seepage and hydrologic modification.)

The DMWW brief incorporates many arguments, but the key is that it argues that agricultural stormwater does not include the discharge of groundwater. One is puzzled to figure out that stormwater does not seep into the ground and become groundwater. In fact, DMWW claims that stormwater is water that is not absorbed by the soil and only moves across the surface of the land. It claims “This does not include the groundwater that carries nitrate pollution.” DMWW would gut the agricultural stormwater discharge by saying only sheet flow on your farmland is exempted by the agricultural stormwater exemption. DMWW’s brief claims that it is undisputed that the discharge of nitrate is created by groundwater and not by stormwater.

Clearly the writers of the brief have no understanding of the amount of natural nutrients in the soil and that nitrates would be discharged without any addition of inorganic nitrogen to grow crops.

The brief describes EPA’s efforts in 1973 to exempt agricultural runoff from CWA permitting and how the courts reversed EPA’s action and declared discharges from agriculture could be point sources. Congress quickly corrected the court’s error. DMWW virtually ignores Section 319 of the CWA, which specifically deals with nonpoint sources of pollution. Section 319 explains how the states are to control nonpoint source pollution and virtually no one recognizes Section 319 allows the states to develop their own “regulatory” program to control nonpoint sources. Section 319 even requires the Attorney General of a state to sign off on whether there is sufficient regulatory authority by the state to control nonpoint sources.

DMWW essentially argues the drainage districts’ pipes and ditches are not nonpoint sources and do not enjoy the benefit of agriculture’s stormwater runoff exemption. DMWW argues that because agricultural stormwater is channeled through a drain, it automatically becomes a point source. This argument has been tried numerous times and has failed.

It is now up to the court, once again, to protect the agriculture stormwater runoff exemption. 

The opinions of the author are not necessarily those of Farm Futures or Penton Agriculture.