PAOLA, Kan. — Ahead of the vote to potentially create Kansas’ newest city, the Miami County Board of Commissioners are hosting a series of study sessions to get expert testimony about how creating that city could affect the county overall. 

On Wednesday, Lesley Rigney, district manager and watershed coordinator for the Miami County Conservation District, spoke to commissioners about how warehouse development has affected water quality at Hillsdale Lake.  

“I think we can apply common sense and say 5,000-6,000 acres of impervious [land use] in a 30,000-acre watershed is going to have [a] significant impact on the system. I don’t think there is any chance that it wouldn’t,” Rigney said. 

During her testimony, Rigney referenced the Hillsdale Lake Watershed Protection plan and the 2013 Southwest Johnson County Area Plan, which state the area near Gardner Road and 199th Street was originally intended to be used for conservation development. Conservation development typically encourages development patterns where 40% or more of the space is devoted to conservation or left as open space.

Last week water experts from KDHE told commissioners private homes, businesses and warehouses all contribute to water runoff that can lead to pollutants entering waterways. 

Rigney said she would still be concerned if the property was developed into a large residential complex instead of a warehouse, but the amount of runoff from private homes and warehouses are not at the same scale. 

“To me it’s about the order of magnitude. We’re not seeing housing developments come in and take 100 acres of the best agricultural land in the area and pave over 100 acres at a time,” Rigney said. “There are ways to do both types of development that will create less damage to our streams systems. I do not think that we are doing that in either case right now.” 

Rigney said in the last decade (2010-2020) Big Bull Creek saw a 6% increase in urban land use and a 25% decrease in pasture land. In that same time Little Bull Creek saw a 27% increase in urban land use and a 20% decrease in pasture land. 

Rigney said water that comes off impervious surfaces like concrete instead of being absorbed into the ground can cause damage to banks throughout the watershed.

“If we don’t have base flow in the stream we have no water in there holding our banks stable year-round. That’s what happens in an urbanized watershed. An urbanized watershed, you cut that water table off,” Rigney said.

“Everything flows straight into the stream. It just basically works as a conveyance channel. It’s just moving water, it’s not a functioning stream system that’s supporting aquatic life.” moving water, it’s not a functioning stream system that’s supporting aquatic life.” 

With more development planned for Logistics Park KC, Rigney worries if no additional steps are taken to manage water runoff from large industrial developments, it could start affecting local wildlife. 

“Once this is built out as proposed by Logistics Park KC, a very quick and simple GIS analysis tells us that we will now be at the 20% impervious cover benchmark,” Rigney said. “We start to see impacts on sensitive streams that support sensitive aquatic habitats at 10%. Once you get to about 20-25%, you really start seeing stream systems that are unable to support aquatic life.” 

Rigney said right now the watershed is sitting at about 16% impervious cover. 

The Miami County Board of Commissioners will continue hearing expert testimony for the potential incorporation of the City of Golden on Wednesday, September 8 at 9 a.m.