by Julie Ann Madden
Because of Iowa’s population density bordering Union County, county officials are now required to enact an ordinance regulating stormwater discharges.
Union County Planning Director Dennis Henze informed the commissioners of this at their May 14 meeting.
He had been contacted by the South Dakota Department of Environment & Natural Resources (DENR) that Union County had reached a population threshold which requires this ordinance.
It’s based on the 2010 Census, explained DENR Surface Water Quality Program Administrator Kelli Buscher. When an area meets a certain population per square mile, it becomes classified as an urbanized area. Because of the population density across the border in Iowa, it pulled Union County into an urbanized area classification.
“Turner, Lincoln, Minnehaha counties and several cities have met that magical threshold, too,” said Henze.
As I understand it, it’s any time any soil’s disturbed, predominantly in construction sites, a stormwater discharge permit will be required,” said Henze, adding he will attend a meeting on this in the near future. “Dakota Dunes and Wynstone (developments) already have a policy.”
“Most contractors abide by it,” he said, explaining contractors install silt fencing at construction sites, barriers in ditches and gutters to prevent soil erosion into stormwater systems. “It hopefully keeps soils out of the rivers.”
“My understanding is you just have to adopt a county policy,” said Henze, adding he believes the DENR has a generic policy available for the county to use as a model.
This new ordinance may affect farmers, too, he said. “There may be regulations that require them to do something — especially with all the tiling that goes on and ditch cleaning. I don’t know yet.”
“It could create more inspections on our part,” said Henze, noting in the southern end of the county the culprit is wind erosion. “Wind really blows the sand around. That’s the biggest reason for silt fencing.”
Union County is part of the Sioux City Urbanized Area.
As defined by the Bureau of the Census, “an urbanized area is a densely settled core of census tracts and/or census blocks that have population of at least 50,000, along with adjacent territory containing non-residential urban land uses as well as territory with low population density included to link outlying densely settled territory with the densely settled core. It is a calculation used by the Bureau of Census to determine the geographic boundaries of the most heavily developed and dense urban areas,” according to EPA’s Stormwater Rule II Final Rule Urbanized Areas: Definition and Description.”