Where the river runs: Boise and flooding have always gone hand-in-hand

What is now the campus of Boise State University, and before that the city’s airport, was once an island in Boise River. In every spring flood the river divided, with the south branch running close to the Bench.

In May 1876, high water carried away the bridge to that island and the Idaho Statesman printed a long list of all the damage done. In June that year the main course of the river was in the south channel, and the branch nearest town was “nearly dry.” Blacksmith George Washington Stilts told the paper that he was about to start placer mining there. Since Stilts was a notorious practical joker, he could have been only kidding.

On June 6, 1876, contradicting the report that the river was nearly dry, the Statesman noted: “The Ferry Boat which is to take the place of the old bridge on Boise River was launched Sunday. The wire rope will soon be up and everything lovely.” The flood that took out the bridge had also damaged the dirt streets of the town. In December the Statesman issued a “TIMELY WARNING” and urged people most likely to suffer damage to prepare for the usual spring flood by building levees. The orchards of Thomas Jefferson Davis occupied much of the land next to the river at what is now Julia Davis Park.

In April 1881, “Boise River is booming and considerable fear is entertained that the bridge will go off; but many reports are circulated about the condition of the bridge that are not true. Thus far the bridge is safe, and teams are passing over it constantly. It is thought by those who are very good judges that the bridge will stand a foot and a half more rise. That much more would do much serious damage to the farmers down the valley. If the warm weather continues for a week longer we may look for a good deal higher water. There is plenty of snow in the mountains, but we seldom have over a week of warm weather at any one time. A slight change gives us cooler nights and then the water slacks up, and in this way heavy snows pass off without swelling the water much higher than the farmers can stand.” We don’t know whether Statesman readers took much comfort from these comments, but we doubt that farmers did.

Thomas Davis had a force of men at work strengthening the banks of the river next to his orchards with stone and sagebrush in May 1884, while work on a new bridge “went bravely on” as a strong force of men and teams was kept steadily at work along the banks above the site of the bridge. While this was going on several boats were kept busy ferrying people and goods across the river.

In May 1892, “Boise River is on its annual rampage. The Chinese who own gardens near the river are fearful lest their vegetables be transported to a damp market in the vicinity of Caldwell. Ten years ago the main channel was where the ‘second’ river now runs. It is feared it will do this again.”

In May, 1896, in what was probably the 19th century’s most costly flood, the river was so high that the island between north and south channels was nearly all under water. The Ninth Street Bridge could not be used because the approaches to it had been washed away. Seven acres of Chinese gardens near Central Addition on the north side of the river were washed over.

The Statesman noted: “Milk famine looms if the south side of the river is cut off from the city. Frank Dunlap drove his cows across the river to this side yesterday.” On June 3, 1896, the river was still rising, and was “cutting through the Davis Grove and heading for the main part of town.” Next day the Broadway bridge was rendered impassable when the river washed away one of its approaches. On June 6, 1896, “great relief” was felt when the river fell 18 inches.

Not until the 20th century, when Arrow Rock, Anderson Ranch and Lucky Peak Dams were built, was Boise Valley spared major Boise River floods, although we still get smaller ones.

This story was originally published October 7, 2017 at 10:58 PM with the headline "Where the river runs: Boise and flooding have always gone hand-in-hand."