The land directly north of Sioux City is quite hilly and all drains into Perry Creek. In early July of 1909 very heavy rains fell into this area. The creek began to rise. By July 9 the creek was out of its banks.
The Crescent Park area and a large area around West Ninth Street were the hardest hit.
Four blocks of downtown businesses had been flooded along with much of the west side.
The electric power plant located at Third and Water was unable to operate. This shut down all the electrically driven trolley cars in the city.
A conduit (large pipe) that carried the flow of the creek under Fourth and Water street was not large enough to carry the large flow of water coming down the creek. Basements were flooded and much damage was done to streets, houses, and bridges.
Two people lost their lives in the flood. The damage to buildings was estimated to be more than $750,000.