In the spirit of the State's solar energy focus, and to serve the needs of the publicand those involved in the design and implementation of solar energy systems, we decided to present the readily available weather and climatic data relating to 1) solar energy and 2) the demands for energy. This report is essentially a solar data compendium for Illinois. It contains a minimum of text and consists mainly of tables and graphs, largely assembled from a wide variety of publications (many not easily found).
The effects of river traffic on water and sediment inputs into a side channel were studied in an 18-month research project. McEver's Island, located in the Illinois River, was selected as the study site. The objectives of the research project were: 1) to collect data on factors such as suspended sediment load, water discharge, and types of sediment at a reach of a side channel which directly connects with the main river; and 2) to attempt to estimate the rate of movement of the sediment and water into a side channel in different river stages.Observations indicated that the wave height, velocity, and suspendedsediment concentration showed some significant changes during the passagesof barges. The amounts of water and sediment inputs into side channelsare relatively small compared with the background main channel dischargesand sediment loads.
The Fox Chain of Lakes is a series of interconnected glacial lakes that are essentially located along the main stem of the Fox River. Originating in Wisconsin, the Fox River flows through northern Illinois before becoming a major tributary of the Illinois River. About 75 percent of the Fox River above the lowest section of the Fox Chain of Lakes lies in Wisconsin. The drainage area above the lowest point of the chain is about 1,184 square miles. The Fox Chain of Lakes has a surface area of more than 6,000 acres. Over the years, significant land-use changes have occurred on this watershed. These changes and the geographical location of the Fox River have resulted in extensive sediment deposition within these lakes. This is especially true for those lakes in the direct path of the Fox River. For example, Grass Lake and Nippersink Lake have lost most of their capacities to sediment deposition. The average depth of Grass Lake in 1975 was 2.7 feet, and the sediment is extremely soft. Within the present research activity, the original research conducted in 1974-1975 by the authors is being examined along with additional data collected by others within the last 25 years. These initial analyses indicated that both in-lake and off-lake sediment management techniques must be implemented to increase water depths within the lakes and decrease sediment loads. Among the in-lake management alternatives that should be considered are dredging and disposing of sediment outside the lake, discharging hydraulically dredged sediment into geotubes or some other type of containment facility within the lake, and creating artificial islands within the lake with dredged sediments. The watershed-based sediment management alternatives could include implementation of best management practices on the watershed, flow and sediment retention basins, side channel sediment traps, sediment management within the stream channel, and the implementation of a systemwide sediment management alternative.
The long-term temporal trends of water quality in the Illinois Waterway system upstream of Peoria are described in this report. The time period investigated was from 1965 to 1995. The seasonal Kendall trend test was used to detect statistically significant trends. A related test, the seasonal Kendall slope estimator, was used to calculate the magnitude of the trend. Box plots were also used to visualize differences in data over time. The water quality analytes considered in this report include dissolved oxygen, ammonia-nitrogen, nitrate and nitrite-nitrogen, total Kejeldahl nitrogen, total phosphorous, sulfate, turbidity, total suspended solids, fecal coliform, cyanide, and phenol. Water quality was generally found improved at all stations. Substantial improvements were found at most stations for dissolved oxygen, the nitrogen species, phenol, and cyanide concentrations. Fecal coliform densities generally decreased at most locations. Little or variable change was found for turbidity, total suspended solids, and total phosphorus concentrations. Increasing trends were detected for sulfate concentrations.
A field-scale project in Mason County, Illinois, was performed to monitor the movement of nitrate in ground water beneath an irrigated field. Chemical tracers were used to assess the migration of solutes both laterally and vertically under the influence of an irrigation well and to determine the amount of recycling at a site due to irrigation pumpage and the amount of off-site transport of nitrate due to regional ground-water flow. Water samples from the sand aquifer at the site reveal considerable spatial and temporal heterogeneity in aqueous chemistry. Recharge is rapid in this system, and it is probable that the water chemistry of the recharge water also is variable spatially and temporally; it is especially influenced by agricultural practices. Nitrate (NO3-) concentrations are elevated in a zone between approximately 15 and 30 feet (ft) beneath the surface, although this zone was not persistent laterally or with time. The maximum nitrate concentrations in this zone were slightly greater than 20 milligrams per liter (mg/L) as nitrogen, well above the drinking water standard of 10 mg/L. Nitrate was generally absent below 30 ft in the aquifer, probably due to denitrification reactions. The tritium data suggest that vertical movement of solutes in the aquifer is rapid, and that there has been enough time to transport solutes from the surface or soil zone to depths in excess of 100 ft. Because drinking-water wells generally are screened well below the zone of elevated nitrate concentrations in this area, it appears that fertilizer applications do not have a negative effect on drinking-water quality for most homeowners. From the results of tracer tests, the effects of irrigation pumping on solute transport are measurable but not substantial. Tracer movement both horizontally and vertically was slight under pumping conditions, less than 10 ft horizontally and between 1 and 2 ft vertically about 100 ft from the irrigation well after three days of pumping. The vast majority of nitrate applied in this area is not being recycled through the irrigation wells.
This report documents the structure and the use of an improved version of the Windows-based interface of the unsteady flow model, UNET. This interface was developed by the Illinois State Water Survey for the Office of Water Resources, Illinois Department of Natural Resources. The current version of the interface program can download historic, real-time, and forecasted stage and flow data from U.S. Geological Survey, U.S. Army Corps of Engineers, and National Weather Service Web sites interactively. These data can be used to update an existing Data Storage System (DSS) database or to create new ones. The interface allows the user to create or update gaging station information in a Microsoft Access database. The user can create project files to run the UNET model for historic, design, real-time, and forecasted flood events. The graphing function allows plotting of single and multiple hydrographs, or stage profiles of a single reach and multiple reaches. The utility tools include screen captures, document editing, and DSS file editing. This interface program uses the original UNET generic geometry and boundary condition files to maintain the same level of accuracy as the UNET model, but it also allows the user to change some of the parameters, such as, the simulation time interval, time windows, and numerical Corant number, and etc., in the BC file. Real-time simulation of a flood event simulates flood stage profiles using real-time stage and flow data downloaded from related Web sites. Locations and magnitudes of levee overtopping will be displayed for the lower Illinois River should these occur. The interface program lets the user modify parameters to simulate simple levee failure or two types of complicated embankment failures, overtopping and piping. Simulations also can be performed using the modified levee information, such as breaches or revised crest elevations. The change of water surface elevation induced by modifying levees can be compared with another simulation graphically and also in table format. Stage profiles from all simulations can be plotted together with levee heights on both sides of the channel along the Lower Illinois River to visually show the impacts of particular floods.
This document provides pertinent information on the spatial distribution characteristics of extremely heavy rainstorm events in Illinois and the Midwest. Relations were developed for those storms in which maximum rainfall at the center equaled or exceeded the point maximum experienced on the average of once in 100 years or longer. The study was limited to this group of storms because of existing needs for information on these extreme storm events in the design and operation of water control structures in small basins. It is recommended for use in conjunction with Illinois State Water Survey Bulletin 70, Bulletin 71 (Midwestern Climate Center Research Report 92-03), and Water Survey Circular 173 for runoff computations related to the design and operation of runoff control structures in small basins subject to extreme rainfall events. Area-depth relations were derived from information obtained through operation of several dense raingage networks, detailed field surveys and analyses of severe rainstorms in Illinois, analyses of heavy rainstorms in a six-basin hydroclimatic study, and exceptional storms recorded by the climate network of the National Weather Service in Illinois. Using data and information from these sources, curves defining spatial distributions for storms of various areal extent were derived. Results are presented in a form readily adaptable for use by hydrologists or other interested users.
In 1997, the Illinois State Water Survey, at the request of the University of Illinois, initiated a test drilling project that included the construction of several 2-inch diameter observation wells at two sites on the Urbana-Champaign campus. The project concentrated on two areas in which cooling water was needed by the University the North Chiller Plant and the Abbott Power Plant. The purpose of the project was to determine whether sufficient ground-water resources could be located from which to develop a water supply. Exploration at both sites focused on sand-and-gravel materials within the Glasford Formation of Illinoian Age. The main area of interest was the North Chiller Plant at the intersection of Clark and Mathews Streets in Urbana, located in the SE of Section 7, T.19N, R.9E. (Urbana Township), Champaign County. If warranted by test drilling results, a seven-day aquifer test was proposed at the site to investigate the potential of pumping approximately 500 gallons per minute (gpm) from production wells. An area of secondary interest was the Abbott Power Plant between Armory and Gregory Streets and just east of the Illinois Central railroad tracks, located in Section 13, T.19N., R.8E. (Champaign Township). Testing at the Abbott site, if warranted, would examine the feasibility of developing 200 gpm from production wells. Exploratory test drilling at both sites, along with additional information from earlier reports and data on file, led to the following conclusions. The Glasford aquifer is present at most sites across the University of Illinois campus, although it varies considerably in both thickness and texture. The texture of the deposit appears to be finer in test holes south of Green Street. The top of the Glasford sand, near University Avenue, commonly occurs at elevations of 615 to 620 feet. However, the top of the sand at the Abbott Power Plant occurs much lower; the top of the aquifer occurs at about 595 feet. The bottom of the sand is more uniform and occurs at both plants at an elevation of approximately 565 feet. A shallower sand occurs at an elevation of about 640 feet, that is not considered part of the Glasford aquifer. It appears oxidized and occurs just below a very dark brown zone, presumably the Robein Silt. The depth to water in study wells finished in the Glasford aquifer is about 115 feet. Ground-water levels in the Glasford aquifer have a natural fluctuation of about 1 to 2 feet in the test holes. Water levels at the North Chiller Plant did not appear to have been affected significantly by water withdrawals at the Northern Illinois Water Corporation East Well Field. Levels were observed to be similar to levels reported in the 1930s. Water in the Glasford aquifer tends to be alkaline, very hard, high in iron concentration, and at a nearly constant temperature of about 57 degrees F. Although there had been some concern about potential contamination of the Glasford aquifer from fuel spills at the Abbott Power Plant, no contamination was evident in samples taken from test wells constructed for this project. Despite their relative proximity to the former locations of University Wells 10 and 11, no test holes drilled near the North Chiller Plant and Beckman Institute indicated a sufficient thickness of suitable sand material in the Glasford aquifer to warrant construction of a test well to conduct an aquifer test at the desired rate of 500 gpm. Test drilling at the Abbott Power Plant indicated a sufficient thickness of Glasford aquifer present to warrant an aquifer test at perhaps 100 gpm. Accordingly, well designs are recommended for the construction of two test wells or production wells at that site, which might be capable of producing the desired quantity of 200 gpm.
This report summarizes the results of surveying conducted at the mouths of five deltas on Peoria Lake in 1999. The five deltas are at the mouths of Richland Creek, Partridge Creek, Blue Creek, Dickison Run, and Farm Creek. All surveying was done to include the planform of the deltas that existed in 1999. The 1999 planform of four of the five deltas except Dickison Run is different than the locations in 1902-1904. In order to estimate the volumes of deposited sediment between 1902-1904 and 1999, a grid was developed encompassing the aerial extent of the 1999 delta. Subsequently, computations determined the net volumetric accumulation of sediment within each grid for each delta: 2,683 acre-feet (Partridge Creek), 1,495 acre-feet (Blue Creek), 1,428 acre-feet (Richland Creek), 1,252 acre-feet (Farm Creek), and 338 acre-feet (Dickison Run). Relative values of the sediment accumulation could be quite misleading since most of these creeks have been altered over the last 100 years, the 1999 outlets are not at the same locations as those that existed in 1902-1904, and a significant amount of sand-and-gravel mining took place at several locations such as at Farm Creek. Still these values provide a significant contribution toward the understanding of the relative magnitudes of sediments being deposited at the mouths of these five deltas.
In 1993, with funding from the Long Range Water Plan Steering Committee (LRWPSC), the Illinois State Water Survey (ISWS) and the Illinois State Geological Survey (ISGS) began a study of the sand-and-gravel aquifers in southwest McLean and southeast Tazewell Counties to estimate the availability of ground water and determine the hydrogeologic feasibility of possibly developing a regional water supply. The study area includes the confluence of the buried Mahomet and Mackinaw Bedrock Valleys (confluence area) and contains part of one of the largest sand-and-gravel aquifers in Illinois, the Sankoty-Mahomet Sand aquifer. The study had two goals: (1) to determine the quantity of water a well field in the Sankoty-Mahomet Sand aquifer could yield, and (2) to determine the possible impacts to ground-water levels and existing wells that might occur in the Sankoty- Mahomet Sand aquifer and overlying aquifers from the development of a well field pumping 10-15 million gallons of water a day (mgd). Two major tasks were completed to meet the study goals. The first task was a hydrogeologic characterization of the glacially deposited (glacial-drift) aquifers within the confluence area. Results of the hydrogeologic characterization were published in 1995 (Herzog et al., 1995a and b) and a summary of their findings are in the appendices. The second task, and the subject of this report, was the development of a computer-based, mathematical model of the ground-water flow in the glacial deposits (ground-water flow model). The ground-water flow model was used to simulate the effects of a hypothetical well field for various locations within the study area and to provide an estimate of the amount of ground water a regional well field could yield from the Sankoty-Mahomet Sand aquifer within the confluence area. The characterization of the hydrogeology of the glacial-drift aquifer system was simplified to allow the development of a ground-water flow model. The generalized hydrogeology resembled a layer cake with uneven layers, some of which were discontinuous. The layers included relatively impermeable bedrock overlain by three sand-and-gravel aquifer layers that are generally separated by aquitard layers. Due to the complexity of the spatial distribution of the sand-and-gravel deposits above the Sankoty-Mahomet Sand aquifer, these shallower deposits were generalized as two aquifer layers. Although none of the aquifer deposits represented by the shallower aquifer layers are capable of sustaining a 10-15 mgd water supply, the thickness, distribution, and hydraulic properties of these deposits are important for a complete understanding of the hydrology of the model area. In some parts of the area covered by the ground-water flow model, two or more of the aquifer layers are in direct contact, providing a 'window' of hydraulic connection between the aquifer layers. In other parts of the model area, one or more of the aquifer layers are absent. Using the information from the hydrogeologic mapping and water-level data, chloride concentrations, and percent modern carbon data from observation wells, an updated conceptual understanding of the groundwater flow system for the Sankoty-Mahomet Sand aquifer was developed that described the movement of ground water into and out of the model area. Ground water in the Sankoty-Mahomet Sand aquifer generally flows through the Mahomet Bedrock Valley from the southeast, westward to the Illinois River and northward through the Mackinaw Bedrock Valley. The natural ground-water discharge areas for the Sankoty-Mahomet Sand aquifer in the study area are the Mackinaw River in the west-central part of the study area and Sugar Creek in the southwestern part of the study area. In some areas very close to the rivers, ground water is flowing upward from the Sankoty-Mahomet Sand aquifer through the upper aquifers and into the stream beds. There is a slight hydraulic gradient (slope) east of the model area that steepens where the flow enters the study area, even though the aquifer volume increases. This slope increase is caused by a greater amount of recharge entering the aquifer due to hydraulic connections with overlying aquifers. The areas of connection are more numerous in the west and north portions of the model area, as demonstrated by increases in water levels, decreases in chloride concentrations, and increases in modern carbon isotope concentrations in the Sankoty-Mahomet Sand aquifer. Down gradient of these connections, the chloride concentrations remain low, which suggests that the influx of ground water through these connections provides the majority of the recharge in these areas. Water pumped from the Normal west well field south of Danvers, which has wells penetrating into one of these upper aquifer connections, has low chloride values, indicative of water coming from the upper sands. Although the size of the original study area was about 260 square miles, the area to be modeled (model area) was expanded to 1,100 square miles. This expansion was necessary to reduce the effects of the model boundary conditions on simulated water levels in the study area. The simulated water levels are strongly influenced by the boundary conditions, which reduce the accuracy of the simulated water levels near the boundaries. The ground-water flow model was developed using Visual Modflow software. Three aquifer layers sandwiched between four aquitard layers are simulated in the model. Bedrock forms the lowest aquitard; till units form the others. The hydraulic property values of each hydrogeologic unit were assigned to the corresponding layer in the ground-water flow model where the unit was present. When a unit was absent, the layer was assigned the value of an overlying or underlying hydrogeologic layer. The model's boundary conditions control the regional flow into and out of the study area, discharge to and from the streams, infiltration from precipitation, and removal of water by production wells. The model was calibrated to match water levels measured in area wells in 1994 and to match the baseflow gains and losses in the Mackinaw River and Sugar Creek. The mean absolute error of the simulated water levels was 4.99 feet, which was only slightly greater than the errors associated with the potentiometric surface maps, indicating a good match between the model and the characterization of the ground-water flow system. The ground-water flow budget calculated using the model shows that 80 percent of the water coming into the model is from infiltration of precipitation, 11 percent is from the regional Mahomet aquifer in the east, and 8 percent is from river leakage. The budget also shows that 57 percent of the surface and ground water that leaves the model area does so through discharge to the rivers, 33 percent to the regional ground-water flow to the north and to the west, and the remaining 10 percent to existing production wells. (See online pub for remining abstract...)