Research about Dubuque, Iowa

USGS1985

Discharge ratings for control gates at Mississippi River Lock and Dam 11, Dubuque, Iowa

The water level of the navigation pools on the Mississippi River are maintained by the operation of tainter and roller gates at locks and dams. Discharge ratings for the gates on Lock and Dam 11, Dubuque, Iowa, were developed from current-meter discharge measurements made in the forebays. Methodology is given to accurately compute the vertical gate openings of the tainter gates. Discharge coeffients, in equations that express discharge as a function of tailwater depth, headwater depth, and vertical height of gate opening, were determined for conditions of submerged-orifice and free-weir flow. A comparison of the rating discharges to the theoretical rating discharges is given for submerged orifice flow for the tainter and roller gates.

Iowa↗

USGS1973

Flood of August 2, 1972, in the Little Maquoketa River basin, Dubuque County, Iowa

Flood peaks with magnitudes from 2 to 3 times the SO-year flood occurred on streams in the Little Maquoketa River basin for the flood of August 2, 1972. Up to nine inches of rain fell in the headwater of the Middle Fork tributary with six to seven inches occurring over most of the Little Maquoketa River basin. The flood peak elevation at the gaging station near Durango exceeded the 1925 flood of record by 1.7 feet. Flood damages were extensive to crops, roads, and bridges. Many of the homes in Durango, Daytonville, and Sageville were inundated to some extent and were evacuated. Flood damages were estimated to be over one million dollars. No loss of life or personal injuries were sustained. Flood-peak discharges at 12 sites, basin rainfall, a description of the 1972 flood, brief accounts of other major floods in the basin, maximum flood peaks in northeastern Iowa, selected flood-frequency data, and annual floods of record at 5 sites are given.

Iowa↗