Will the St. Joseph River Flood Again

Southward Curve -- It was the concluding week of March 1950, and Due south Bend Mayor George A. Schock watched as the St. Joseph River rose out of its banks, forced out by heavy rains.

Riverside Drive was inundated, the h2o lapping at the steps of houses perched on the embankment. Floodwaters crept perilously close to houses on Emerson Avenue near Northside Boulevard after filling the avenue and edging over sidewalks. Parks about the river "diameter the burden of the overflow," a Tribune commodity at the fourth dimension said.

Schock said the city had no plans for overflowing emergencies. South Bend had never faced such a threat from the river, he said.

Less than a week later, it happened again. A 2nd, more devastating rising and crest of the river sent floodwaters back into the aforementioned areas. Schock said there was piddling urban center departments could practice to spare the Emerson Avenue residents a 2nd inundation in as many weeks.

"A flood of such proportions was wholly unexpected," Schock said, according to a Tribune written report on April 5, 1950. "Subsequently the river crested concluding week engineers assured me the channel would exist able to hold it."

Final month, 68 years later, a strikingly like scene unfolded.

Riverside Drive once once again became nearly indistinguishable from the river, aside from homes that were again waterfront backdrop. Floodwaters again surrounded homes on Emerson Avenue, prompting firefighters to make boat rescues of stranded residents. Segments of numerous streets closed to traffic as the floodwaters inundated them.

"Nosotros're at present at a 500-yr flood level and the forecast is suggesting that nosotros've got about another foot to go," Mayor Pete Buttigieg said on Feb. 21 along Michigan Street, near the submerged Leeper Park.

The river crested that night at 12.7 feet with an estimated streamflow of 22,700 cubic anxiety per second, according to the National Atmospheric condition Service. It is the highest marking e'er recorded at the river approximate, located at the city wastewater treatment plant on Riverside Drive. The mark obliterated the previous record of 10.nine feet and 19,500 cubic anxiety per second set in March 1982 and equaled in January 1993.

The scenes that took place last calendar month have happened time and once more — Riverside Bulldoze submerged, homes along Emerson Avenue threatened, Leeper Park covered in water. Dramatic images aside, putting this twelvemonth's alluvion into perspective with the floods of history is non an easy chore. Should the definition of a "500-twelvemonth-overflowing" alter? The lack of data is the get-go trouble.

For starters, the S Bend river gauge was not installed until the early on 1980s. Information technology is besides not tied into the U.South. Geological Survey'southward network of river monitors. That means making authentic comparisons of river crests over decades is a alpine gild.

Elsewhere along area rivers, the gauges have a longer history. Gauges along the St. Joseph River appointment back to 1930 in Niles and 1947 in Elkhart. The gauge along the Elkhart River in Goshen has been in service since 1931. On the Yellow River in Plymouth, in that location has been a river judge since 1948. All are tied into the U.Southward. Geological Survey.

The origin of the proverbial "100-year flood" lies with the U.S. Geological Survey. According to a written report from the USGS Water Science School, the federal government in the 1960s sought a method for putting context effectually flooding events knowing that the circumstances that crusade floods vary and non all floods are equal in magnitude, elapsing or event.

The government's solution was to use a 1-pct probability as the basis for the National Flood Insurance Program.

The "1-percent annual exceedance probability" is the statistical probability that a like inundation event will occur in a given year, said Tom Weaver, with the United states of america. Geological Survey Upper Midwest Water Science Eye in Lansing.

In essence, it means at that place is a 1 in 100 adventure of a flood meeting or exceeding the 1-percentage probability. Similarly, a 500-year flood means in that location is a ane in 500 chance of that level being met or exceeded in a given twelvemonth.

Cara Grabowski, manager of marketing for South Bend's Department of Public Works, said it was this U.Southward. Geological Survey guidance, besides as the Federal Emergency Direction Agency's National Inundation Hazard maps, that formed the footing of the mayor's assertion that South Bend experienced a 500-twelvemonth inundation last month.

"To the all-time of our knowledge, this flood is unprecedented in the history of our urban center. Just anecdotally, I tin can remember in one case in a while seeing the river get-go to jump the banks on Riverside at Leeper Park," Buttigieg said in an interview Fri. "I think nigh of us can remember seeing Howard Park get under once in awhile when there'southward a bound melt and high water, but this was nearly two feet in a higher place the highest level in recorded history."

Setting the stage

In guild to send the St. Joseph River out of its banks at a historic clip, a variety of factors had to come together.

First, information technology was an unusually snowy February. Co-ordinate to forecasters with the National Weather Service northern Indiana office, Due south Curve saw 29.half-dozen inches of snowfall during the month — 14.six inches above normal. The largest storm, which came just x days before tape-breaking rainfall and flooding, left a heavy, wet snowpack of greater than a foot, with an estimated 1.v to i.75 inches of liquid in the snowpack.

South Bend as well obliterated its all-fourth dimension rainfall record for the month of February with 8.08 inches — 6.13 inches to a higher place normal. The previous record, set in 1976, was 5.23 inches.

The three-day rainfall from February. nineteen-21 that triggered the rapid cook of the snowpack and the intense rise of streams, creeks and rivers set up a number of other records. The 3.73 inches that fell on February. 20 became the all-fourth dimension rainiest day in February. In addition, it is the single-rainiest day e'er in South Curve between the months of December and May.

"This was a large frontal arrangement that stalled out in our area," said Geoffrey Heidelberger, a meteorologist with the National Atmospheric condition Service. "When information technology stalled out, it allowed the pelting to ... go over the same areas over and over once more."

Like scenes played out beyond the region as the St. Joseph River in Niles, the Elkhart River in Goshen and the Yellow River in Plymouth all broke crest records. There were h2o rescues in Osceola, Elkhart, and Goshen. Rice Field at Elkhart Central High Schoolhouse was submerged, as it was in 1985.

In Due south Curve, there is a history of large-scale flooding along the St. Joseph River.

In Tribune coverage of the 1993 overflowing, Doris Henderson recounted flooding at her Emerson Artery home during the floods of 1982 and 1985 and said she wasn't moving.

"It'south not like it was in 1982 or 1985," she said in a story published Jan. half dozen, 1993. "It hadn't come up to the yard even so...but information technology drives yous nuts thinking nearly it."

The Feb 1985 overflowing crested at 10.seven feet or xix,100 cubic feet per second, according to the conditions service.

It was some other similar story in early January 2008 when a combination of heavy snow the week before and and then heavy rains sent the St. Joseph River out of its banks.

The pair of floods that challenged Mayor Schock in March and Apr 1950 peaked at 19,453 and 25,646 cubic anxiety per second respectively. Tribune coverage at the fourth dimension of those floods likewise noted that the highest recorded streamflow was a March 1908 flood when the river's streamflow was measured at 27,000 cubic feet per 2nd. All three of those floods, however, were measured from the Twin Co-operative dam simply east of Mishawaka.

In that location are also historical accounts of significant flooding events along the St. Joseph River in the 19th century, pre-dating the city's incorporation in 1865.

Travis Childs, director of instruction at The History Museum in South Bend, said there was a sudden rising on Jan. xv, 1847 from water ice flowing down the river. The river backed up from South Curve to Mishawaka and caused the river to rise three feet higher up flood stage in 15 minutes.

"Most citizens thought at that place would be no promise in saving anything in the industrial center of the metropolis," Childs said. "Non long later on the river surged to 12 feet in a higher place flood stage and water rose to the 2nd flooring of the buildings along the East and W Races."

Residents helped close the head gates of the West Race and held dorsum most of the water.

In another instance in June 1855, several inches of rain fell and the river reached a level of 2 feet above its previous high-water mark.

"The head-gates of the East Race couldn't take the force and information technology complanate sending a torrent of water, copse and droppings down the race," Childs said. "Somewhen the Eastward Race was indiscernible from the remainder of the St. Joseph River."

Childs said later on in the same flood the Colfax span had its foundations washed abroad and plunged into the river.

Moving forward

One key event in the wake of the floods is whether the dynamics accept changed enough that scientists and government officials are asking the right questions and using the right statistics. It also raises the question of what activeness cities can take.

"The bigger question really is exercise we accept the right statistics around how often these extreme rain and flood events happen," Buttigieg said. "Has their frequency fundamentally changed or are we only in an unusually rainy time? I retrieve the more than nosotros become our arms around that the more we apply it to guide decisions in the future about planning, preparedness, land utilise and everything else nosotros need to know to become ready."

Mishawaka Mayor Dave Wood said the city's "long-term planning and strategic investment in infrastructure over several decades" helped the city escape "serious problems" from last week'southward flooding, even though some of its parks were swamped.

The city has kept its floodplains for urban center parks, where it builds structures with physical that can withstand the high water temporarily. He pointed out that the street lamps, congenital to exist waterproof, in Beutter Park stayed on even while the park was flooded. And the Riverwalk is congenital to "shed water quickly," he said.

Also, the urban center doesn't place its own buildings in the floodplain, Forest said, and discourages homes and other development in the floodplain.

Buttigieg pointed to the last year and a half in South Bend as evidence that "something is irresolute." In that span, the metropolis has seen a 500-year flood and what the weather service deemed a 1,000-year pelting upshot, when 8.49 inches of rain barbarous in a 24-hour period betwixt Aug. fifteen and 16 of 2016.

"We're dealing with either a remarkable coincidence statistically or perhaps the beginning of a more permanent change in our vulnerability to flooding," he said.

Tribune reporter Joe Dits contributed to this report.

RBlake@SBTinfo.com

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@TheBobBlake

Notable river crests in South Bend

Date	Crest, in anxiety	Estimated streamflow (cubic feet per 2nd)
February. 21, 2018	12.7	22,700
Jan. 6, 1993	x.9	19,500
March 15, 1982	10.nine	19,500
Feb. 24, 1985	x.seven	xix,100
Jan. 9, 2008	nine.6	17,200