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Geology topics

A.R. Schmidt

Publications and source records attributed to A.R. Schmidt.

9 recordsLinked to original sources
USGS1994

Measurements of leakage from Lake Michigan through three control structures near Chicago, Illinois, April-October 1993

A total of 213 measurements of leakage were made at three control structures near Chicago, Ill.--the Chicago River Controlling Works (CRCW), Thomas J. O'Brien Lock and Dam (O'Brien), and Wilmette Pumping Station (Wilmette)--using acoustic Doppler current profilers (ADCP's) and dye-dilution techniques. The CRCW consists of the Chicago Lock and two sets of sluice gates connected by a network of harbor walls. Leakage measurements were made in April, May, July, September, and October 1993 using an ADCP. The mean and standard deviation of leakage measured by the ADCP for the Chicago Lock river gate were 133 and 39 cubic feet per second, respectively. The mean and standard deviation of the leakage measurements at CRCW were 204 and 70 cubic feet per second, respectively. The mean and standard deviation of leakage measurements at O'Brien on September 17, 1993, were 21 and 10 cubic feet per second, respectively. The mean and standard deviation leakage measured at Wilmette using the ADCP were 59 and 8 cubic feet per second, respectively, in April 1993. After the pump bays at Wilmette were sealed in July 1993, the leakage dropped to less than 15 cubic feet per second in September 1993. Discharge estimated by dye-dilution at the Chicago Lock on July 15, 1993, was 160 cubic feet per second, or within 8 percent of the discharge measured with the ADCP. (USGS)

Water-Resources Investigations Report↗
USGS1993

Water-level, velocity, and dye measurements in the Chicago tunnels

On April 13, 1992, a section of a 100-year-old underground freight tunnel in downtown Chicago, Illinois was breached where the tunnel crosses under the Chicago River, about 15 meters below land surface. The breach allowed water from the Chicago River to flow into the freight tunnels and into buildings connected to the tunnels. As a result, utility services to more than 100 buildings in downtown Chicago were lost, several hundred thousand workers were sent home, and the entire subway system and a major expressway in the Loop were shut down. The breach in the tunnel was sealed and the tunnel dewatered by the U.S. Army Corps of Engineers (Corps) and its contractors. The U.S. Geological Survey (USGS) assisted the Corps in their efforts to plug and dewater the freight tunnels and connected buildings. This assistance included the installation and operation of telemetered gages for monitoring water levels in the tunnel system and velocity measurements made in the vicinity of the tunnel breach. A fluorescent dye tracer was used to check for leaks in the plugs, which isolated the damaged portion of the Chicago freight tunnel from the remainder of the tunnel system.

Conference Paper↗
USGS1992

Floating sample-collection platform with stage-activated automatic water sampler for streams with large variation in stage

A floating sample-collection platform is described for stream sites where the vertical or horizontal distance between the stream-sampling point and a safe location for the sampler exceed the suction head of the sampler. The platform allows continuous water sampling over the entire storm-runoff hydrogrpah. The platform was developed for a site in southern Illinois.

Illinois↗
USGS1987

Data-collection methods and data summary for the assessment of water quality in Cedar Creek, west-central Illinois

A water-quality, data-collection network on a 26.2-mile reach of Cedar Creek in west-central Illinois was operated from May through December 1985 and from March through October 1986. The study reach drains a 60.8-square-mile area of predominantly agricultural land. However, the city of Galesburg contributes combined- and storm-sewer discharge to the creek that can affect the water quality. This report presents the streamflow and water-quality data collected and describes the methods and instrumentation used. Continuous discharge data were determined at eight gaging stations--five on the main stem and three on tributaries of Cedar Creek. Flows ranged from 0 to 1,200 cubic feet per second. A total of 8 storm sewers and 51 combined sewers were monitored or inspected as part of the study. Continuous precipitation data were collected at five sites. The maximum hourly precipitation intensity during the study period was 1.97 inches per hour. The maximum total precipitation for a storm during the study period was 4.16 inches. Sediment-oxygen-demand rates were measured at 45 locations in the creek. The measured sediment-oxygen-demand rates ranged from 0.4 to 9.1 grams of oxygen per square meter per day. Ninety-seven bottom-material samples were collected and analyzed for chemical oxygen demand, percentage of volatile organic constituents, and concentrations of total organic plus ammonia nitrogen, arsenic, cadmium, chromium, copper, iron, lead, manganese, mercury, and zinc. Traveltime and reaeration rates were determined for 15 subreaches of Cedar Creek during various flow conditions. The reaeration rates ranged from 3.10 to 20.8 per day. Three intensive diel (24-hour) data collections were conducted during low-flow conditions. Data included dissolved oxygen concentration, biochemical oxygen demand, nutrient concentrations, and metal concentrations. During storm-related high-flow conditions, water-quality samples were collected at 5 main-stem sites, 3 tributary sites, the Galesburg wastewater treatment-facility outfall, and 15 sewer outfalls. These samples were analyzed for nutrients and metals, suspended solids, chemical oxygen demands, and biochemical oxygen demands. This report describes methods for measuring stage, discharge, precipitation, sediment oxygen demand, traveltime, and reaeration rate. Collection methods for bottom-material samples, diel water-quality data and samples, combined-sewer overflow frequency and duration, and storm- related sampling of combined sewers, storm sewers, and streams are described. A brief discussion of streamflow computation methods also is presented.

Open-File Report↗
USGS1987

Assessment of water quality and factors affecting dissolved oxygen in the Sangamon River, Decatur to Riverton, Illinois, summer 1982

Water quality and processes that affect the dissolved-oxygen concentration in a 45.9 mile reach of the Sangamon River from Decatur to Riverton, Illinois, were determined from data collected during low-flow periods in the summer of 1982. Relations among dissolved oxygen, water discharge, biochemical oxygen demand, ammonia and nitrite plus nitrate concentrations, and photosynthetic-oxygen production were simulated using a one-dimensional, steady-state computer model. Average dissolved oxygen concentrations ranged from 8.0 milligrams per liter at the upstream end of the study reach at Decatur to 5.2 milligrams per liter 12.2 miles downstream. Ammonia concentrations ranged from 45 milligrams per liter at the mouth of Stevens Creek (2.6 miles downstream from Decatur) to 0.03 milligram per liter at the downstream end of the study reach. Un-ionized ammonia concentrations exceeded the maximum concentration specified in the State water quality standard (0.04 milligram per liter) throughout most of the study reach. Model simulations indicated that oxidation of ammonia to form nitrite plus nitrate was the most significant process leading to low dissolved oxygen concentrations in the river. (USGS)

Water-Resources Investigations Report↗
USGS1986

Assessment of low-flow water quality in the Du Page River, Illinois

The relations of several stream processes to concentrations of dissolved oxygen and other constituents during low-flow periods were evaluated for a 70.3-mile reach of the Du Page River in northeastern Illinois, using measured data and computer simulations. Reaeration rates and traveltimes were measured at various flow rates using a steady-state gas-tracer technique. Stream discharge, stage, temperature, and chemical constituent concentrations were measured during two 24-hour periods in July and August 1983. These data were used to describe water quality and to calibrate and verify the QUAL-II one dimensional, steady-state, water quality model. Dissolved oxygen concentrations did not meet the State water quality standards in several subreaches of the Du Page River. Concentrations were consistently below the State minimum dissolved oxygen standard in the downstream 8 miles of the East Branch Du Page River. Model simulations indicate that although ammonia oxidation played a role in the dissolved oxygen depletion, the primary factor was sediment oxygen demand. Other measured chemical constituents that did not comply with the State water quality standards in several subreaches of the river included ammonia, iron, fluoride, and total dissolved solids. (USGS)

Water-Resources Investigations Report↗
USGS1986

Assessment of low-flow water quality in Richland Creek, Illinois

To study the effects of urbanization on water quality, the relations of several stream processes to concentrations of dissolved oxygen and other constituents were evaluated during low-flow periods for a 30.1-mi reach of Richland Creek in southwestern Illinois. The study used both measured data and computer simulations. Reaeration rates and traveltimes were measured at various flow rates using a steady-state, gas-tracer technique. Sediment-oxygen demands were measured at several locations throughout the study reach. Stream discharge, stage, temperature, and chemical-constituent concentrations were measured during two 24-hr periods in July and August 1984. The data were then used to describe water quality and to calibrate and verify the QUAL-II one-dimensional, steady-state, water quality model. (USGS)

Water-Resources Investigations Report↗