08-20-18 Health and Public Saftey & Utilities

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r�CITY OF SOUTH BEND I OFFICE OF THE CLERK He went on,I wanted to give some background on the river that runs through our city. I remember my boss,John Fisher always saying,the St. Joseph River is a good river. I don't know if his mind has changed, he does live in South Bend. He said it is a good river because it doesn't flood as much as other rivers do in other states. He explained, The total drainage area is about 4,800 square miles. That in itself is roughly three (3)to four(4)times the size of Rhode Island, so it's draining a lot of area. It is about two-hundred (200) miles long, and the slope from Hillsdale Michigan where it begins, to Lake Michigan is about three (3) feet per mile. One(1)of the other things I want to point out is that there are twelve (12) dams along the length of the river. Of those twelve (12), there are several that are under Federal Energy Regulatory Commission regulations. Of those that are under this jurisdiction, the dams along the river were originally built for power. They weren't built for flood mitigation or recreation, but a lot of them have turned into that. Those that produce power are regulated, and they have to have a license through the Federal Regulatory Commission. As part of that license, they are required to maintain a water surface elevation upstream of their dam, of an envelope of roughly six (6) inches. He continued,There was a lot of talk while the flooding was going on as to why these dams weren't holding back water, and why they were letting out water. What those structures were doing was operating per their FERC requirements. That means water is coming in, and they have to let that much water out. That is something that is usually part of 401 Water Quality Certification that is put on them by the Indiana Department of Environmental Management. That is the way that a lot of the environmental agencies have had these dams go, so they don't really have the ability to be used as flood control. They have to operate within their license, unless they get to the point where they can't pass any more water. Then the water just continues to rise. Those dams were operating within their FERC license. He went on, On the next slide (referencing the presentation which is available in the City Clerk's Office), we want to get into the storm events. We've talked a lot about snow fall, temperature, rain fall and those things, but I want to touch on how the February event truly happened, and try to relate that to some other flood events we've seen. Flooding and storm events are very odd things. No event tends to be the same as another. Rain can fall in one(1)area and it be totally dry in another. We deal with that quite a bit in this part of the state. He continued, If you look around areas of the country, like areas along the coast, one (1) of the worst things that can happen is a hurricane. The storm surge could be one (1) of the worst things that happen to them. People who live in mountainous regions worry about storms coming in and stalling and dumping water into one(1) spot. We worry about what happened in February as water resource engineers. We get a lot of snow falling, a lot on the ground, the ground is saturated, and temperatures start to warm up,then we get a lot of rain. Those tend to be the storms that we worry about as our worst-case scenarios in this part of the country. He went on,In February,the first ten(10)of eleven(11)days of the month,we saw snowfall. The maximum actual snow pack depth was about fifteen(15) inches. Total snowfall for February was about twenty-nine and a half(29.5)inches,which is fourteen and a half(14.5)inches above normal. So not only did we have a lot of snowfall, we had snowfall that is above normal for the month. This all occurred within the first seventeen (17) days of the month. Based on records from the National Weather Service, it is the seventh (7th) snowiest February that we've had on record. If EXCELLENCE I ACCOUNTABILITY I INNOVATION I INCLUSION EMPOWERMENT 455 County-City Building 227W Jefferson Bvld I South Bend.Indiana 46601 p574.235.9221 f574.235.9173 TTD 574.235.5567 i www.southbendin.gov 3