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Research about Des Moines, Iowa

Source-linked reports with geographic coverage including Des Moines, Iowa.

7 recordsLinked to original sources
USGS2024

Groundwater flow model for the Des Moines River alluvial aquifer near Des Moines, Iowa

Des Moines Water Works (DMWW) is a regional municipal water utility that provides residential and commercial water resources to about 600,000 customers in Des Moines, Iowa, and surrounding municipalities in central Iowa. DMWW has identified a need for increased water supply and is exploring the potential for expanding groundwater production capabilities in the Des Moines River alluvial aquifer, where it operates two radial collector wells (RCWs). The U.S. Geological Survey, in cooperation with DMWW, completed a study of the Des Moines River alluvial aquifer and interactions of the RCWs with the aquifer; no previously published model has included the existing well locations, which is the focus of this model. A conceptual and numerical groundwater flow model have been developed to characterize the Des Moines River alluvial aquifer under existing conditions, to simulate water levels observed in the RCWs, and to provide publicly accessible hydrologic data and research that advance understanding of the regional hydrologic system and can potentially be used in the future to evaluate groundwater production scenarios. Model performance was assessed by comparing observed and simulated groundwater levels that included water level elevations, water level changes, water level inequality observations, surface water streamflow, and change in surface water volume from upstream to downstream. Water table elevation in the aquifer layers is on average slightly overestimated with average absolute value error less than 1.5 meters at both RCWs and less than 2.5 meters for all observation wells in the alluvial aquifer layers. The model also accurately simulated water tables greater than the RCW design minimum (a water level threshold at which RCW pumping is reduced) in all timesteps for which water level observation data existed. Water table elevation error was higher in other model layers that were not the focus of the study, and the model did not accurately match streamflow targets.

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USGS2024

Quantitative microbial risk assessment with microbial source tracking for mixed fecal sources contaminating recreational river waters, Iowa, USA

Fecal contamination of surface water can cause acute gastrointestinal illness (AGI) among recreators. AGI risk varies among human, livestock, and wildlife fecal sources, but the prevalence of individual sources is unknown for most recreational sites. We estimated AGI risk for six sites near Des Moines, Iowa, using quantitative microbial risk assessment combined with microbial source-tracking (MST). Water samples ( n = 147) collected over two years were tested for 36 qPCR assays quantifying waterborne pathogens and MST markers specific to avian, bovine, human, and porcine fecal sources. Average swimming risk across all sites was 5 (95% CI: 0.0030–142) to 67 (16–215) AGI cases per 1,000 recreators. Individual fecal sources were rarely associated with swimming exposures where risk was >36 AGI cases per 1,000 recreators; most high-risk exposures were associated with simultaneous occurrence of multiple fecal sources. Iowa’s beach action value for Escherichia coli (235 MPN/100 mL) identified >90% of high-risk exposures at five of six sites, so was generally protective of public health in this setting. For sites influenced by mixed fecal sources, results illustrate that identifying a single dominant source of risk is less important than recognizing the number of unique fecal sources that impact AGI risk.

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USGS2023

Application of geophysical methods to enhance aquifer characterization and groundwater-flow model development, Des Moines River alluvial aquifer, Des Moines, Iowa, 2022

Des Moines Water Works (DMWW) is one of the largest water providers in Iowa and as population growth continues, demand for drinking water is increasing. DMWW uses groundwater and surface water as raw water sources to supply the City of Des Moines and surrounding communities. In response to current and future demands, DMWW is in need of a thorough understanding of local groundwater resources, specifically the Des Moines River alluvial aquifer. The Des Moines River alluvial aquifer is hydraulically connected to the Des Moines River and consists of alluvial deposits and glacial outwash sands and gravels. To ensure a sustainable groundwater supply, additional information to better understand and manage groundwater availability within the Des Moines River alluvial aquifer would be beneficial. Beginning in 2018, DMWW partnered with the U.S. Geological Survey to construct a groundwater-flow model to increase understanding of the hydrologic system in the Des Moines area. The model hydrogeologic framework will be enhanced by using multiple geophysical methods of data collection in the Des Moines River, Beaver Creek, and the Des Moines River alluvial aquifer that could provide a better understanding of the geology in the model area.

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USGS2022

A steady-state groundwater flow model for the Des Moines River alluvial aquifer near Prospect Park, Des Moines, Iowa

The Des Moines River alluvial aquifer is an important source of water for Des Moines Water Works, the municipal water utility that provides residential and commercial water resources to the residents of Des Moines, Iowa, and surrounding municipalities. As an initial step in developing a better understanding of the groundwater resources of the Des Moines River alluvial aquifer, the U.S. Geological Survey constructed a steady-state numerical groundwater flow model in cooperation with Des Moines Water Works to simulate water-table elevations in the Des Moines River alluvial aquifer near Prospect Park in Des Moines under winter low-flow conditions. A simple conceptual model consisting of a hydrogeologic framework, water budget, and inferred water-table elevation map was developed for the model area. The inferred water-table elevation map was constructed based on general knowledge of hydrogeology within the model area and was used to set calibration targets for numerical model calibration. A steady-state numerical model was constructed based on the conceptual model using MODFLOW-NWT to simulate an area of about 15 square kilometers near Prospect Park in Des Moines. Parameter ESTimation software was used for model calibration to assess and optimize performance of the horizontal hydraulic conductivity and recharge parameters. The numerical groundwater flow model and supporting data are available in the USGS data release associated with this report, which contains the model archive. Performance of the calibrated steady-state model was assessed by comparing observed and simulated water-table elevations, as well as estimated and simulated contributions to streamflow within the model area. The difference between observed water-table elevations and simulated water-table elevations was −0.1 meter at the majority of calibration targets, with the negative value indicating an overestimation of the simulated water-table elevation value compared to the observed water-table elevation value, and the root mean square error was 0.13 meter, which represents about 20 percent of the difference in observed water-table elevations. The simulated value of contributions to streamflow within the model area was considered similar to the estimated value, increasing confidence in the ability of the model to accurately represent the groundwater flow system in the Des Moines River alluvial aquifer in the model area during winter low-flow conditions.

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USGS1996

Delineation of flooding within the upper Mississippi River Basin — Flood of June 18 through August 4, 1993, in Des Moines and vicinity, Iowa

This hydrologic investigations atlas shows the areas in and near Des Moines, Iowa, that were flooded by the Des Moines and the Raccoon Rivers and Walnut, Fourmile, and Beaver Creeks from June 18 through August 4, 1993. This map also depicts the Federal Emergency Management Agency 100-year flood boundaries. The area drained by the Des Moines River upstream from Des Moines received more than 100 percent of normal rainfall in May, June, and July, 1993. At Boone, which is located about 35 miles north-northeast of Des Moines, July rainfall was 424 percent of normal. The discharges at streamflow- gaging stations on the Des Moines River near Stratford, downstream from Saylorville Lake, and at Des Moines are shown. The cumulative discharge for inflow-gaging stations in the Des Moines area and discharge for the Des Moines River below the Raccoon River at Des Moines from July 8 through 21, 1993, are shown. The water-surface elevations of Saylorville Lake from June 18 through August 4, 1993, are shown. Profiles of the maximum water- surface elevations of the Des Moines and Raccoon Rivers during the 1993 flood in Des Moines and vicinity are higher than the respective Federal Emergency Management Agency 100- and 500-year flood profiles.

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USGS1966

Water-surface profiles of Raccoon River at Des Moines, Iowa

This investigation was undertaken as a part of the cooperative program with the Iowa Institute of Hydraulic Research, the City of Des Moines, and the U.S. Geological Survey. The purpose of this report is twofold: 1. To present water-surface profiles and rating curves for existing channel conditions in the 4-mile reach of Raccoon River upstream from the mouth, and 2. To show the effect upon water-surface profiles of raising the Fleur Drive roadway to eliminate road overflow. The Raccoon River., having a drainage area of 3,630 square miles, borders the south edge of the Des Moines downtown business district before flowing into the Des Moines River at mile 201.6. A large residential area and the city airport are separated from downtown Des Moines by the Raccoon River (fig. 1). Five highway bridges and one railroad bridge span the river between the mouth and mile 205.75, the limits of this report (fig. 1). The river is confined to a narrow channel from the mouth to the Chicago, Burlington, and Quincy Railroad bridge (mile 202.6); upstream of this bridge the river is not confined and during high water spreads over a wide flood plain. Fleur Drive, a principal traffic artery to the downtown area, is the only roadway of the five that crosses this wide flood plain. It has been flooded 15 times during the period 1903, 1918-1965.

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