The river in flood: 1982, 2016, 2018

March 1982 · August 2016 · February 2018 · the St. Joseph River

The floods as events: A power river is a flood river, and Mishawaka's flood events are carried here at shared size — the gauges and the river's mechanics are Parks & River's, told whole there; the floods as days the town lived through are this entry's. The documented great floods of this reach are a snowmelt river's floods. In March 1982 the rapid melting of a snowpack holding two to six inches of water, with moderate rain, flooded the whole northern tier of Indiana; the U.S. Geological Survey's report on that flood assigns the St. Joseph River's flooding a recurrence interval of about fifty years, and the crest at the South Bend gauge — four miles below the Mishawaka dam — stood at 10.9 feet, the record for that gauge until 2018. In August 2016 a rain flood sent five and a half billion gallons a day through the South Bend reach, on the county's accounting. And in February 2018 came the fullest documented flood in the record this build reached: nearly thirty inches of snow on the ground by February 17, then record February rain — more than eight inches for the month, 3.75 inches on February 20 alone — as the temperature rose above sixty and the snowpack let go. The river crested at South Bend at a historic 12.7 feet on February 22, and at Niles it crested at 17.33 feet, more than two feet above the standing record of 15.10 feet set April 5, 1950.

Mishawaka's part, stated exactly: For Mishawaka itself the contemporary record in hand is plain but general: the mayor of neighboring Warsaw, writing to his own city on March 2, 2018, recorded that "South Bend and Mishawaka suffered similar flooding of the Saint Joe River," and the county emergency figures given out that March counted about 700 homes affected in St. Joseph County, 65 of them with major damage — county figures, not a Mishawaka tally. What the floods took in Mishawaka itself, street by street and house by house, in 1982 and in 2018, is not established in the sources reached for this build: the city's commissioned history carries no flood narrative, and no Mishawaka account of the famous March 1913 flood was reached either — that flood's documented record belongs to the Wabash and Maumee valleys, and the St. Joseph River at Mishawaka has no 1913 crest in the record reached, an absence printed as such. The settling sources are named where the river's record names them: the South Bend Tribune's flood coverage in those years, the city's council minutes, and the USGS peak-flow files for the river's gauges.

Sources:

1. Parks & River section of this history — the floods whole: U.S. Geological Survey, Floods of March 1982, Indiana, Michigan, and Ohio (WRIR 83-4201) and the fifty-year recurrence; the February 2018 figures from the City of South Bend's flood-study testimony (the snow and rain, the 12.7-foot crest of February 22, the prior 10.9-foot record of 1982); the National Weather Service's Niles crests (17.33 feet in 2018 against 15.10 feet on April 5, 1950); the Warsaw mayor's letter of March 2, 2018; the county emergency figures of March 2018; the August 2016 flow on the county's accounting; and the named gaps and settling sources, carried identically here.