NPR Interview-Road Salt
- From
- (deq)
Today | was interviewed by Rebecca Thiele of public radio WKAR-Kalamazoo.
The interview was prompted by the findings of Western Michigan University, Carla Koretsky, regarding
the impact of road salt on a small deep kettle lake within the City of Kalamazoo. We are funding a CMI
monitoring grant for Dr. Koretsky to conduct additional assessment of several urban lakes and the
associated watersheds. | provided the reporter with the 2 attached reports and the link for a another
report prepared by the USGS These reports all have sections
devoted to chlorides and correlate high chloride concentrations in lakes and streams with urban land
use.
Questions-roughly & answers- briefly-no particular order
1. From the 2007 NLA report, Mi lakes have higher conductivities and chloride concentrations than
lakes nationally and within the upper Midwest ecoregion. Why? Speculated that compared to
the rest of nation, particularly compared to the southern states, we have more sources including
road salt. Compared to other states in the upper Midwest ecoregion we have more lakes in
urbanized watersheds.
2. Will monitoring be conducted at other Kettle Lakes with urbanized watersheds to document the
extent of the problem? Acknowledged that elevated chloride levels have been documented in
urbanized areas of Michigan and concentrations in Woods Lake in Kalamazoo are problematic
which is why we are funding additional work to document the extent of the problem and
sources. We will routinely continue to monitor Michigan’s resources for chlorides but the site
specific nature of the problem precludes specific sampling for the issue. We do not have a
Water Quality Standard for chloride but we have not identified toxicity issues where elevated
concentrations have been found.
3. Will construction of roadside retention ditches solve the problem? Explained that best
management practices for the typical NPS pollutants our agency addresses may not be
appropriate for salt. | made sure the reporter had a contact in MDOT.
Air date for the story is unknown.
Mike Walterhouse, Environmental Quality Specialist
Lake Michigan Unit
Surface Water Assessment Section
Water Resources Division, MDEQ
517-284-5548
xxxEND_PAGE:executiveofficeemails21_b0311_0647_0648_2