* Information and data are preliminary and subject to revision unless stated otherwise. *
June 2008 Flood Summary
June 23: USGS crews are once again collecting water-quality samples this week from the flooded rivers in central and eastern Iowa as the water levels go to below flood stage. The flood-related water-quality sampling will be used to document the concentration (amount of contaminant per unit of river water often reported as in milligrams per liter or parts per million) of contaminants in the river during the flooding as well as the total quantity of the contaminants (the total weight of the containment transported by the river over the duration of the flood often reported as grams or metric tons of the containment transported per day or for the flood event). USGS crews are re-visiting numerous streamgaging sites in Iowa to replace or repair equipment as sites become accessible due to receding river stage levels. Additional streamflow measurements will also be made as necessary for verification of the rating curve (relationship between the discharge and stage height of the river) due to changes in the river channel configuration during the extreme flows, levee erosion, and road or bridge overflow. USGS crews will again be deployed throughout central and eastern Iowa this week to identify the high-water marks in selected communities affected by the recent flooding. The community high-water marks will be used for documentation of the urban inundation areas during the flood.
The selected communities that will have high-water marks identified are:
- Cedar Falls, Iowa (Cedar River watershed)
- Cedar Rapids, Iowa (Cedar River watershed)
- Coralville, Iowa (Iowa River watershed)
- Charles City, Iowa (Cedar River watershed)
- Columbus Junction, Iowa (Iowa River & Cedar River watersheds)
- Decorah, Iowa (Upper Iowa River watershed)
- Iowa City, Iowa (Iowa River watershed)
- Marengo, Iowa (Iowa River watershed)
- Mason City, Iowa (Winnebago River/Cedar River watershed)
- New Hartford, Iowa (Beaver Creek/Cedar River watershed)
- Shell Rock, Iowa (Shell Rock River/Cedar River watershed)
- Waterloo, Iowa (Cedar River watershed)
June 20: USGS crews are at the Iowa River near Lone Tree to move the temporary streamgage into the permanent gage after cleaning the gage of debris and mud. There will also be another special discharge measurement on the Mississippi River by the Iowa USGS crew near Quincy, IL. Water quality sampling continued both yesterday and today including the sampling of sediment that was deposited from receding waters in Cedar Rapids by the Cedar River and from the Iowa River at Wapello and Lone Tree. USGS crews have been deployed throughout the Cedar River, Iowa River, and Upper Iowa River basins to locate, identify, and determine elevations of high-water marks on primary bridges. The high-water marks will be used to document the profile of the flood through bridges for Iowa Department of Transportation bridge assessment and future design.
June 19: The previously submerged streamgage on the Cedar River in Cedar Rapids was cleaned out and all data collection equipment that was destroyed by the flood was replaced; the temporary streamgage was removed. There was also special stream discharge measurement made of the Iowa River at Wapello due to the extent of levee overflow; the equipment at the streamgage near Wapello was again adjusted to ensure continued operation. Two special discharge measurements were made on the Mississippi River:
Des Moines River at St. Francisville (just above the confluence with the Mississippi River) 101,000 cubic feet per second
Mississippi River at Alexandria, MO (just below the confluence with the Des Moines River) 519,000 cubic feet per second
June 18: Late yesterday (6/17/08), USGS crews completed three measurements on the Mississippi River; Mississippi River at Clinton, 182,000 cubic feet per second (cfs), Mississippi River at Burlington, 432,000 cfs, and Mississippi River above Keokuk, 395,000 cfs. A measurement on Iowa River at Lone Tree, 45,500 cfs, and was made on 6/14/08. USGS crews will continue collecting streamflow and flood-related water-quality measurements.
June 16: Late yesterday, USGS crews completed two measurements on the Des Moines River; Des Moines River at Pella, 97,700 cubic feet per second (cfs), and Des Moines River at Tracy, 102,100 cfs. Today, a streamflow measurement at Des Moines River at Ottumwa was 101,000 cfs. USGS crews are currently (6/16/08) making streamflow measurements on the Des Moines River at Keosauqua, the Iowa River at Wapello, and the Skunk River at Augusta. USGS crews will continue collecting streamflow and flood-related water-quality measurements. All field measurements are immediately going to National Weather Service for calibration for river forecasting.
June 15: Today, streamflow measurements were made at two locations, Iowa River at Iowa City measured 40,800 cubic feet per second (cfs), and Cedar River near Conesville measured 124,000 cfs. USGS crews were still out making streamflow measurements at Lone Tree on the Iowa River ; Pella , and Tracy on the Des Moines River . USGS crews will continue collecting streamflow and flood-related water-quality measurements. All field measurements are immediately going to National Weather Service for calibration for river forecasting.
Photos taken at Coneseville, IA on Cedar River.
June 14: Streamflow measurements were made at two locations on the Iowa River today. Downstream of the Coralville reservoir, streamflow measured 38,300 cubic feet per second (cfs); at Iowa City the streamflow measured 39,300 cfs. Both streamflow measurements exceed previous 1993 flows on the Iowa River . The Cedar River at Cedar Rapids continues to fall from record peak streamflow. USGS crews have repaired the Janesville streamgage on the Cedar River , the Coralville Dam streamgage on the Iowa River , and have relocated the Cedar Rapids streamgage on the Cedar River . USGS crews will continue collecting streamflow and flood-related water-quality measurements over the weekend. All field measurements are immediately going to National Weather Service for calibration for river forecasting.
June 13: As of today, the streamflow measurement on the Cedar River at Cedar Rapids, IA, was 149,500 cubic feet per second (cfs); the previously estimated 500-year flood was estimated at 109,000 cfs. The previous record flow on the Cedar River at Cedar Rapids was 73,000 cfs on March 31, 1961. USGS crews will continue collecting streamflow and flood-related water-quality measurements over the weekend. All field measurements are immediately going to National Weather Service for calibration for river forecasting.
4 streamflow-gaging stations that have been affected by the flood waters:
- Cedar R. at Janesville, IA, station was inundated by flood waters, temporarily offline.
- Cedar R. at Cedar Rapids, IA, new temporary gage installed.
- Iowa R. at Wapello, IA, gage moved to higher ground
- Des Moines R. at Keosauqua, IA, gage moved to higher ground
June 11: Heavy rainfall of up to 10+ inches from thunderstorms the week of June 3 to 10 has caused record flooding across the state of Iowa. This morning water levels were above flood stage at 50 streamflow-gaging stations in Iowa. Today, USGS crews will continue collecting streamflow and flood-related water-quality measurements.
New record stages and/or streamflows have occurred at 14 streamgages:
- Upper Iowa R. at Bluffton, IA
- Upper Iowa R. at Decorah, IA
- Turkey R. Near Eldorado, IA
- S. Fork Iowa R. Blairsburg, IA
- S. Fork Iowa R. Providence, IA
- Winnebago R. At Mason City, IA
- Shell Rock R. At Shell Rock, IA
- Cedar R. at Waterloo, IA
- Cedar R. at Cedar Rapids, IA
- Des Moines R. near Stratford, IA
- Fourmile Creek near Ankeny, IA
- Fourmile Creek at Des Moines, IA
- Fox R. at Bloomfield, IA
- Nodaway R. at Clarinda, IA
National Weather Service Image
5 Day Precipitation Forecast (June 30th - July 5th)