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 Benchmark Sediment Monitoring Program for Illinois Streams was initiated by the Illinois State Water Survey in 1981 to generate a long-term database of suspended sediment concentrations and instantaneous sediment loads. The program is now part of the Water Survey's Water and Atmospheric Resources Monitoring (WARM) Network, which monitors climate, soil moisture, surface water, groundwater, and sediment throughout Illinois. This report summarizes the suspended sediment data collected for the program during Water Years 1998 and 1999. All the techniques used in the data collection process and laboratory analyses are based on U.S. Geological Survey procedures and techniques. The report appendices present tables of instantaneous suspended sediment measurements, particle size analysis, sediment transport curves, and plots of instantaneous sediment concentrations for the period of record for the current monitoring stations.
The Benchmark Sediment Monitoring Program for Illinois Streams was initiated by the Illinois State Water Survey in 1981 to generate a long-term database of suspended sediment transport. The program is now part of the Water Survey's Water and Atmospheric Resources Monitoring (WARM) Network, which monitors the climate, soil moisture, surface water, ground water, and sediment throughout Illinois. This report summarizes the suspended sediment data collected for the program during Water Years 1994 and 1995. All the techniques used in the data collection process and laboratory analyses are based on U.S. Geological Survey procedures and techniques. The report appendices present tables of instantaneous suspended sediment measurements, particle size analysis, sediment transport curves, and plots of instantaneous sediment concentrations for the period of record for the current monitoring stations.
The Illinois River has become a focus of state and federal agencies and other organizations interested in integrated watershed management. As a result, issues related to habitat restoration, floodplain management, navigation, erosion and sedimentation, and water quality of the Illinois River are being discussed at the watershed scale. In support of this effort, the Illinois Scientific Surveys have initiated development of the Illinois Rivers Decision Support System (ILRDSS) for use in documenting project activities within the watershed and assessing and evaluating the effectiveness of potential restoration projects and management practices. The ILRDSS will integrate and expand existing databases and numerical models of segments of the Illinois River into an integrated decision support system (DSS) for the entire Illinois River watershed. New databases and models also will be created for the watershed, as well as a comprehensive ILRDSS web portal to all available data and information about the Illinois River and its basin. This report describes the current status of ILRDSS development and serves as an introduction to those unfamiliar with the Illinois Rivers Decision Support System.
This is the third and final report on the Kankakee River in Illinois supported by the Conservation 2000 Program of the Illinois Department of Natural Resources. For this project, the Illinois State Water Survey mapped the bank erosion of the main stem of the Kankakee River from the Route 30 bridge in Indiana to the mouth of the Kankakee River with the Illinois River near Wilmington, collected about 100 bed and bank material samples, resurveyed all the previously surveyed river cross sections, surveyed four sand bars, and analyzed all historical and new data. This research has shown that of 223.6 river bank miles (includes both sides of the river), about 10.4 river bank miles have severe erosion, 39.4 river bank miles have moderate erosion, 70.8 river bank miles have minor erosion, and the remainder are either protected or stabilized or data are not available. The median diameter of the bed materials varied from 0.27 millimeters (mm) to 0.52 mm. The median diameter of bank materials varied from 0.07 mm to 0.41 mm. Analyses of the long-term flows from six gaging stations in Illinois showed an increasing trend in flows through the 1960s with no discernible increase since that time. Cross-sectional analyses of the river from the Kankakee Dam to the State Line Bridge did show some trends. The river reach from the Kankakee Dam to Aroma Park called Six-Mile Pool has lost 13.4 percent of its capacity due to sediment deposition since 1980. Similarly, Momence Wetland also has lost about 10.2 percent of its capacity since 1980. The section of the river between Aroma Park and Singleton Ditch showed both scour and sediment deposition. In general areas close to Aroma Park exhibited sediment deposition and the middle reach experienced scour. The recurring sand bar at the State Line Bridge area contains about 8,500 cubic yards of additional sediment in 1999 than were measured in 1980. The volumetric measurement of three additional sand bars showed some changes since 1980. The river is accumulating sediments within Six-Mile Pool and Momence Wetland. The middle reach is in semi-equilibrium with some sediment accumulation at several areas. Several management alternatives, both in-channel and watershed-based also are included to assist in the reduction of sedimentation problems of the Kankakee River.
The Illinois Streamflow Assessment Model (ILSAM) is an analytical and information tool developed to predict the frequency of streamflows, and water use impacts on streamflows, for every stream in selected major watersheds in Illinois. The current version of ILSAM was developed to operate on a personal computer having a Microsoft Windows 95/98/2000/NT operating system. The model user can obtain streamflow frequency estimates for any location in the watershed by identifying the desired stream and location. The ILSAM has been developed for use with streams in five such watersheds: the Sangamon, Fox, Kaskaskia, Kankakee, and Little Wabash River. This report includes a description of the steps used to develop ILSAM for application to the Little Wabash River watershed, along with a description of the physical characteristics of the watershed, its surface water hydrology, and the factors that influence streamflow variability. The Little Wabash River watershed is located in the southeastern portion of Illinois and has a total area of approximately 3238 square miles. The river and its major tributaries provide the source of water supply for all of the major communities in the watershed, either through direct withdrawals from the river or from the storage of water in impounding reservoirs. Many of these communities were forced to undertake emergency measures to sustain their water supply from these sources during the major droughts of the early- and mid-1900s. Thus, an understanding of the frequency of low flows and drought flows is critical for assessing surface water availability and yields for these communities. Streamflow frequency predictions produced by the model are also useful for evaluating instream flow levels for the protection of aquatic habitat, providing streamflow estimates for water quality analyses and regulations, and classifying Illinois streams by their hydrologic character for use in watershed management. The hydrologic analyses used to develop the model include evaluating the flow frequency from all streamgage records in the Little Wabash River region, evaluating impacts to flow quantity from dams, water supply, and treated wastewaters, and developing regional equations to estimate flows at ungaged sites throughout the watershed. All streamflow frequency estimates produced by the model are representative of the long-term expected flow conditions of streams, reflecting hydrologic conditions over a base period of nearly 50 years (1952-1999).
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...)
The Illinois State Water Survey (ISWS), under contract to the Imperial Valley Water Authority (IVWA), has operated a network of rain gauges in Mason and Tazewell Counties since August 1992. The ISWS also established a network of ground-water observation wells in the Mason-Tazewell area in 1994. These networks are located in the most heavily irrigated region of the state. The region's major source of water for irrigation, municipal, and domestic water supplies is ground water pumped from thick sand and gravel deposits associated with the confluence of two major ancient river valleys, the Mississippi and the Mahomet-Teays. Relatively recent extreme weather events (e.g., the drought of 1988 and the great flood of 1993) resulted in large fluctuations in ground-water levels in the Imperial Valley area. The purpose of the rain gauge network and the ground-water observation well network is to collect long-term data to determine the rate of ground-water drawdown in dry periods and during the growing season, and the rate at which the aquifer recharges. This report presents data accumulated from the rain gauge and observation well networks since their inception through August and November 1999, respectively. Precipitation is recorded for each storm that traverses the Imperial Valley, and ground-water levels at the 13 observation wells are measured the first of each month. The database from these networks consists of seven years of precipitation data and five years of ground-water observations. At the beginning of the ground-water observations in late 1994, the water levels were at their highest in the five years of observation. These high ground-water levels were the result of the very wet 1992-1995 period when annual precipitation was above the 30-year normals at both Havana and Mason City. From September 1995-August 1997 precipitation in the region was below the 30-year normal. The 1997-1998 observation year had rainfall above the 30-year normal. Ground-water levels in the observation wells mirrored these rainfall patterns, showing a general downward trend during the dry years and a recovery in the wet 1997-1998 year. Seasonal increases in the ground-water levels were observed at most wells during the late spring and early summer, followed by decreases in August-November ground-water levels. Analysis indicates that the ground-water levels are affected by both the precipitation in the Imperial Valley area and the Illinois River stages. The observation wells closest to the Illinois River show an increase in water levels whenever the river stage is high. Generally, the water levels in the wells correlate best with precipitation and Illinois River stages one to two months before the water levels are measured, i.e., the June ground-water levels are most highly correlated with the Illinois River stage or precipitation that occurs in either April or May. The analyses conducted indicate the need for continued operation of both networks due to inconsistencies associated with ground-water levels, precipitation, and the Illinois River stage. For instance, the Mason-Tazwell observation well number 2 (MTOW-2) is located near the center of Mason County well away from the Illinois River, but it has an equal correlation with the Illinois River stage and the precipitation in the area. Additional analysis needs to be undertaken to explain this unusual finding.
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.