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CITY OF SOUTH BEND I OFFICE OF THE CLERK
<br /> He went on, When I went for a walk with my family on January 5th at Potato Creek State Park, we
<br /> were very surprised. When we got back to the car, we had a lot of ticks on our dog. This was a
<br /> relatively warm day, it was about fifty (50) degrees Fahrenheit. But, there had been freezing
<br /> temperatures prior to that time. So, these (referencing a slide in the presentation) are deer ticks.
<br /> They are a small tick that carry Lyme Disease in some cases. They actually have an anti-freeze
<br /> component to their life cycle. So, a short period of freezing temperatures or even longer will not
<br /> kill them. And when the warm temperatures come on a particular day, they become almost
<br /> immediately active. So,this suggests that there may be recreational opportunities for people in the
<br /> winter time because it's warmer but there are also hazards that will emerge at this time.These ticks
<br /> could be a serious health threat if they carry Lyme Disease.
<br /> He continued, We also see changes in precipitation, as I've shown you already. So, if you would
<br /> remember, we have increasing winter precipitation and increasing spring precipitation, but it is
<br /> warmer, so the phase of this precipitation will be different. We have the rain versus snow aspect
<br /> of this. So, this metric we compare the percent precipitation falling as snow. So, we look at all of
<br /> the precipitation that falls from November to March and we look at what fraction of that is falling
<br /> as snow. So again,looking at just St.Joseph County, about forty percent(40%)of the precipitation
<br /> that comes in the winter time falls as snow, historically. Again, if we go out all the way to the
<br /> 2080s and look at the RCP eight-point five (8.5), the worst-case scenario, we see about sixteen
<br /> (16) days. We still have a snow occurring in South Bend, so winter will not go all the way away
<br /> and we will still have snow, but we will have significantly less in those months. This has some
<br /> very significant impacts and I think we have had some recent experience with things I will show
<br /> you in just a moment. Winter flooding and stormwater impacts is one (1) impact pathway that
<br /> absolutely is affected by this. Water may be positively affected in that we may have greater
<br /> recharge coming in the winter months. So, we are going to have a lot of events where we have
<br /> snow and then rapid melting. Thinking back to this winter, actually this is very much an analog
<br /> for how climate change might look. We have snow, but it doesn't last very long. So, higher soil
<br /> moisture in winter and spring is very likely to be there because instead of that snow being stored
<br /> on the surface, we have melting that increases the soil moisture. That creates precursors for these
<br /> large flooding events.We also expect to see erosion in transported nutrients from farm lands.These
<br /> fallow fields are no longer covered with snow and the snow armors the landscape and stops those
<br /> nutrients from being washed into the rivers. So, if we have intense rain storms in the winter time,
<br /> which we expect, maybe even thunderstorms in the winter time, then we expect to see a lot more
<br /> nutrients washed into the rivers which ultimately effects the Great Lakes and many other water
<br /> bodies down-stream.
<br /> He went on, So these are just a few pictures. This is the aftermath of record-breaking rain fall that
<br /> occurred in August 2016. This is my son and a neighbor canoeing on our park. We had about eight
<br /> (8)inches of rain that occurred in twenty-four(24)hours. That is about a 1,000-year rainfall event.
<br /> Then, we had record-breaking flooding of the St. Joseph River in South Bend in February 2018.
<br /> According to the calculations that my graduate students and I did, this was a 2,5000-year flood.
<br /> This was caused by an intense rain on snow. So, we had a lot of snow on the ground that rapidly
<br /> melted, sort of priming the pump if you will, then we had over five (5) inches of rain over three
<br /> (3) days which created this perfect storm of flooding. My neighbor was severely impacted. This
<br /> (referencing a picture in the presentation) is my basement with 8,000 gallons of water in it. That
<br /> is about knee-deep. So, the sewers were blocked up and there is a floor drain but it's trying to
<br /> prevent the sewage from coming into the house. So, nothing could get out and the ground water
<br /> was coming in from the sides and not having anywhere to go.There were many finished basements,
<br /> EXCELLENCE ACCOUNTABILITY INNOVATIONINCLUSION EMPOWERMENT
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<br /> 455 County-City Building 227 W.Jefferson Bvld South Bend,Indiana 46601 p 574.235.9221 f 574.235.9173 TTD 574.235.5567 www.southbendin.gov
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