Geology topics

Charles G. Crawford

Publications and source records attributed to Charles G. Crawford.

At least 55 records · Page 3Linked to original sources

USGS1991

Estimation of suspended-sediment rating curves and mean suspended-sediment loads

Suspended-sediment loads are often estimated from an empirical relation between suspended-sediment load ( L ) and streamflow ( S ). This relation is usually defined as a power function, L = aS h , and is referred to as a suspended-sediment rating curve. This function can be formulated as either a linear or non-linear model to find the solution of the rating-curve parameters ( a and b ). Formulation of the power function as a linear model requires a logarithmic transformation to linearize the function and a subsequent correction for transformation bias. Rating-curve parameter estimates for both the bias-corrected, transformed-linear or non-linear models can be obtained by the method of least squares. Each model has distinct advantages and disadvantages. A unique solution of the parameters of the transformed-linear model may be obtained algebraically. These parameter estimates have some optimal properties when certain attainable conditions are met. However, the parameter estimates must be corrected for transformation bias when obtained this way. Parameter estimates obtained for the non-linear model do not require a correction for transformation bias. However, these estimates must be obtained by iterative methods which do not always converge to a solution. In addition, the residual errors of the non-linear model typically are not identically distributed throughout the range of streamflow values. This problem adversely affects the precision of the parameter estimates. Weighted non-linear least squares can be used to improve the parameter estimates for the non-linear model, but the weights must be approximated and their appropriate form may be difficult to determine. A simulation study was done to evaluate: (1) the accuracy and precision of parameter estimates for the bias-corrected, transformed-linear and non-linear models obtained by the method of least squares; (2) the accuracy of mean suspended-sediment loads calculated by the flow-duration, rating-curve method using model parameters obtained by the alternative methods. Parameter estimates obtained by least squares for the bias-corrected, transformed-linear model were considerably more precise than those obtained for the non-linear or weighted non-linear model. The accuracy of parameter estimates obtained for the biascorrected, transformed-linear and weighted non-linear model was similar and was much greater than the accuracy obtained by non-linear least squares. The improved parameter estimates obtained by the biascorrected, transformed-linear or weighted non-linear model yield estimates of mean suspended-sediment load calculated by the flow-duration, rating-curve method that are more accurate and precise than those obtained for the non-linear model.

Journal of Hydrology↗

USGS1991

Effects of advanced treatment of municipal wastewater on the White River near Indianapolis, Indiana: Trends in water quality, 1978-86

No abstract available.

Indiana↗

USGS1990

Effects of surface coal mining and reclamation on the geohydrology of six small watersheds in West-Central Indiana

Six small watersheds in west-central Indiana were selected for study of the hydrologic effects of surface coal mining and reclamation. The watersheds include mined and reclaimed, mined and unreclaimed, and unmined agricultural land uses and are each less than 3 square miles in area. Surface-water, ground-water, and meteorologic data for the 1981 and 1982 water years were used to describe and compare hydrologic systems of the six watersheds and to identify hydrologic effects of mining and reclamation. Discharge at the unreclaimed watersheds was continuous during the study period, whereas discharge at the other watersheds was intermittent and more variable. Peak discharges were greater at the agricultural watersheds than at the unreclaimed watersheds, primarily because of large final-cut lakes in the unreclaimed watersheds. Annual runoff was greatest at the unreclaimed watersheds, intermediate at the agricultural watersheds, and least at the reclaimed watersheds. Hydrologic effects of mining were identified by comparing the hydrologic systems at mined and unreclaimed watersheds with those at unmined agricultural watersheds. These comparisons indicate that surface coal mining without reclamation can increase base flow, annual runoff, and ground-water recharge to the bedrock; reduce peak flow rates and variation in flow; lower the water table in upland areas; change the relation between surface- and ground-water divides; and create numerous, local flow systems in the shallow ground water. Hydrologic effects of reclamation were identified by comparing the hydrologic systems at mined and reclaimed watersheds with those at mined and unreclaimed watersheds. Reclamation can decrease base flow, annual runoff, and recharge to the bedrock; increase peak flow rates, variation in flow, and the response to thunderstorms; reestablish the premining relation between surface- and ground-water divides; and create fewer local flow systems in the shallow ground water. Hydrologic effects of mining and reclamation were identified by comparing the hydrologic systems at mined and reclaimed watersheds with those at unmined agricultural watersheds. The presence or absence of a large final-cut lake in the reclaimed watershed greatly influences the hydrologic systems and the effects of mining and reclamation. Surface coal mining and reclamation can decrease base flow, annual runoff, and peak flow rates; increase the variability of flow and recharge to the bedrock; reestablish the premining relation between surface- and ground-water divides; and lower the water table in upland areas.

Indiana↗

USGS1988

Suspended-sediment characteristics of Indiana streams, 1952-84

Suspended sediment concentration and discharge data were collected at seven daily record stations and 70 partial record stations in Indiana during 1952-84. Median suspended sediment concentrations ranged from 24 to 61 mg/L at daily record stations; concentrations ranged from 6 to 539 mg/L at partial record stations. Most suspended sediment transported in Indiana streams is silt and clay size (particles between 0.062 and 0.004 and < 0.004 mm in diameter). Large suspended sediment concentrations were associated with storm runoff but not always with peak streamflow. Some peak concentrations of suspended sediment preceded peak streamflow by as much as 18 to 30 hr during storms. Suspended sediment concentrations frequently were largest during a storm that occurred after a period of low streamflow, when large amounts of sediment were eroded and transported into the stream and little base flow was available for dilution. For most of the streams studied, reliable predictive equations could not be developed to quantify the relation between suspended sediment concentration and streamflow because of the extreme variability in the data. Annual suspended sediment yields at four daily record stations ranged from 186 to 1,914 tons/sq mi. Annual suspended sediment yields for 70 partial record stations, estimated by use of the suspended sediment transport, flow-duration-curve method, ranged from 11 to 2,310 tons/sq mi. However, because of the poor correlation between suspended sediment discharge and streamflow, these estimates are poor. Periods of record at four daily record and 32 partial record stations were sufficient to test for trends. The trend in suspended sediment concentration, adjusted for streamflow, was significant for only nine of the 36 stations. At six of the nine stations, flow adjusted suspended sediment concentrations decreased with time. (Author's abstract)

Indiana↗

USGS1987

Effects of surface coal mining and reclamation on the geohydrology of six small watersheds in west-central Indiana

The watersheds studied include mined and reclaimed; mined and unreclaimed; and unmined, agricultural land uses, and are each < 3 sq mi in area. Surface water, groundwater, and meteorologic data for the 1981 and 1982 water years were used to describe and compare hydrologic systems of the six watersheds and to identify hydrologic effects of mining and reclamation. Peak discharges were greater at the agricultural watersheds than at the unreclaimed watersheds, primarily because of large final-cut lakes in the unreclaimed watersheds. Annual runoff was greatest at the unreclaimed watersheds, intermediate at the agricultural watersheds, and least at the reclaimed watersheds. Hydrologic effects of mining were identified by comparing the hydrologic systems at mined and unreclaimed watersheds with those at unmined, agricultural watersheds. Comparisons of the hydrologic systems of these watersheds indicate that surface coal mining without reclamation has the potential to increase annual runoff, base flow, and groundwater recharge to the bedrock; reduce peak flow rates and variation in flow; lower the water table in upland areas; change the relation between surface water and groundwater divides; and create numerous, local flow systems in the shallow groundwater. Hydrologic effects of reclamation were identified by comparing the hydrologic systems at mined and reclaimed watersheds with those at mined and unreclaimed watersheds. Reclamation has the potential to decrease annual runoff, base flow, and recharge to the bedrock; increase peak flow rates, variation in flow, and response to thunderstorms; reestablish the premining relation between surface and groundwater divides; and create fewer local flow systems in the shallow groundwater.

Indiana↗

USGS1987

Description of the physical environment and coal-mining history of west-central Indiana, with emphasis on six small watersheds

Information on the geology, geomorphology, soils, climate, hydrology, water use, land use, population, and coal mining history of Clay, Owen, Sullivan, and Vigo Counties in Indiana is summarized. Site-specific information is given on the morphology , geology, soils, land use, coal mining history, and hydrologic instrumentation of the six watersheds which are each less than 3 sq mi in area. The Wabash, White, and Eel Rivers are the major drainages in west-central Indiana. Average annual precipitation is about 39.5 in/yr and average annual runoff is about 13 in/yr. The most productive aquifers are confined or unconfined outwash aquifers located along the major rivers. Bedrock aquifers are regionally insignificant but are the sole source of groundwater for areas that lack outwash, alluvium, or sand and gravel lenses in till. Indiana has more than 17 billion short tons of recoverable coal reserves; about 11% can be mined by surface methods. Almost half of Indiana's surface reserves are in Clay, Owen, Sullivan, and Vigo Counties. More than 50,000 acres in west-central Indiana have been disturbed by surface coal mining from 1941 through 1980. Big Slough and Hooker Creek are streams that drain unmined, agricultural watersheds. Row-crop corn and soybeans are the principal crops. Soils are moderately well drained silt loams, and the watersheds well developed dendritic drainage systems. Unnamed tributaries drain mined and reclaimed watersheds. Ridges of mine spoil have been graded to a gently rolling topography. Soils are well drained and consist of 6 to 12 inches of silt-loam topsoil that was stockpiled and then replaced over shale and sandstone fragments of the graded mine spoil. Grasses and legumes form the vegetative cover in each watershed. Pond Creek and an unnamed tributary to Big Branch are streams that drain mined and unreclaimed watersheds. Soils are very well drained shaly silty loams that have formed on steeply sloping banks. Both watersheds contain numerous impoundments of water and have enclosed areas that do not contribute surface runoff to streamflow. The ridges of mine spoil are covered with pine trees, but much of the soil surface is devoid of vegetation. (Lantz-PTT)

Indiana↗

USGS1987

Statistical analysis of surface-water-quality data in and near the coal-mining region of southwestern Indiana, 1957-80

The Surface Mining Control and Reclamation Act of 1977 requires that applications for coal-mining permits contain information about the water quality of streams at and near a proposed mine. To meet this need for information, streamflow, specific conductance, pH, and concentrations of total alkalinity, sulfate, dissolved solids, suspended solids, total iron, and total manganese at 37 stations were analyzed to determine the spatial and seasonal variations in water quality and to develop equations for predicting water quality. The season of lowest median streamflow was related to the size of the drainage area. Median streamflow was least during fall at 15 of 16 stations having drainage areas greater than 1,000 square miles but was least during summer at 17 of 21 stations having drainage areas less than 1,000 square miles. In general, the season of lowest median specific conductance occurred during the season of highest streamflow except at stations on the Wabash River. Median specific conductance was least during summer at 9 of 9 stations on the Wabash River, but was least during winter or spring (the seasons of highest streamflow) at 27 of the remaining 28 stations. Linear, inverse, semilog, log-log, and hyperbolic regression models were used to investigate the functional relations between water-quality characteristics and streamflow. Of 186 relations investigated, 143 were statistically significant. Specific conductance and concentrations of total alkalinity and sulfate were negatively related to streamflow at all stations except for a positive relation between total alkalinity concentration and streamflow at Patoka River near Princeton. Concentrations of total alkalinity and sulfate were positively related to specific conductance at all stations except for a negative relation at Patoka River near Princeton and for a positive and negative relation at Patoka River at Jasper. Most of these relations are good, have small confidence intervals, and will give reliable predictions of the water-quality variables listed above. The poorest relations are typically at stations in the Patoka River watershed. Suspended-solids concentration was positively related to streamflow at all but two stations on the Patoka River. These relations are poor, have large confidence intervals, and will give less reliable predictions of suspended-solids concentration. Predictive equations for the regional relations between dissolved-solids concentration and specific conductance and between sulfate concentration and specific conductance, and the seasonal patterns of water quality, are probably valid for the coal-mining regions of Illinois and western Kentucky.

Indiana↗

USGS1985

Effects of land use and surficial geology on flow and water quality of streams in the coal-mining region of southwestern Indiana, October 1979 through September 1980

An assessment of streams in the coal-mining region of southwestern Indiana was done from October 1979 through September 1980 during stable stream flows to provide baseline hydrologic and water-quality information and to document the effect of several natural and human-induced factors on water quality in the region. Streams in southwestern Indiana are generally well buffered against acidification from acid-mine drainage because they flow upon calcareous unconsolidated surficial deposits and bedrock. The pH of streams draining forested, agricultural, and reclaimed mined watersheds ranged from 6.3 to 8.8, which is generally within the range of natural waters. The pH of streams draining unreclaimed mined watersheds ranged from 3.8 to 7.9, which was much more variable than for streams draining lands used for other activities. Concentrations of major dissolved constituents in streams affected by coal mining were significantly higher than in streams unaffected by mining. The principal cause of the elevated concentrations of dissolved constituents was the oxidation of pyrite and marcasite and subsequent dissolution of calcite and dolomite. The principal water type of streams draining forested and agricultural watersheds was calcium bicarbonate, whereas the principal water types of streams draining mined watersheds were magnesium sulfate and magnesiumcalcium sulfate. Concentrations of boron, iron, manganese, nickel, and zinc were generally higher in streams draining mined areas than in streams draining forested and agricultural watersheds. Median concentrations of iron and manganese were lower in streams draining reclaimed mined watersheds than in streams draining unreclaimed mined watersheds; this suggests that post-1967 surface-mine reclamation techniques have been effective at reducing concentrations of these metals in streams. Concentrations of aluminum, iron, manganese, nickel, and zinc increased significantly as pH decreased below 6.0 in streams draining unreclaimed mined watersheds. The elevated concentrations of metals in waters and the low pH result from the oxidation of the sulfide in pyrite to sulfate, which releases dissolved ferrous iron, other metals, and acidity into the water. Median suspended-sediment concentrations of samples from streams draining agricultural and mined watersheds were 1.5 and 5.4 times those of streams draining forested watersheds. Suspended sediment in streams was composed primarily of silt and clay-sized particles. The effect of surficial geology on stream quality was evident for several dissolved constituents in forested and agricultural watersheds. In general, pH and concentrations of alkalinity and calcium were significantly higher in streams draining the Wisconsin glacial province than in streams draining the Illinoian glacial province and unglaciated regions. The higher pH and concentrations of these constituents suggests that there is greater dissolution of carbonate minerals in the Wisconsin glacial province than the other regions. Median concentrations of arsenic, lead, and manganese for streams draining the Wisconsin glacial province were significantly lower than for those constituents in streams draining the Illinoian province and unglaciated region. The median cadmium concentration for streams draining the Wisconsin glacial province was lower than for streams draining the unglaciated region. These differences may have been due to lower solubilities of metal and trace elements at higher pH values in the Wisconsin glacial province than in the Illinoian glacial province and the unglaciated region.

Indiana↗

USGS1985

Determination of reaeration-rate coefficients of the Wabash River, Indiana, by the modified tracer technique

The modified tracer technique was used to determine reaeration-rate coefficients in the Wabash River in reaches near Lafayette and Terre Haute, Indiana, at streamflows ranging from 2,310 to 7,400 cu ft/sec. Chemically pure (CP grade) ethylene was used as the tracer gas, and rhodamine-WT dye was used as the dispersion-dilution tracer. Reaeration coefficients determined for a 13.5-mi reach near Terre Haute, Indiana, at streamflows of 3,360 and 7,400 cu ft/sec (71% and 43% flow duration) were 1.4/day and 1.1/day at 20 C, respectively. Reaeration-rate coefficients determined for a 18.4-mile reach near Lafayette, Indiana, at streamflows of 2,310 and 3,420 cu ft/sec (70% and 53 % flow duration), were 1.2/day and 0.8/day at 20 C, respectively. None of the commonly used equations found in the literature predicted reaeration-rate coefficients similar to those measured for reaches of the Wabash River near Lafayette and Terre Haute. The average absolute prediction error for 10 commonly used reaeration equations ranged from 22% to 154%. Prediction error was much smaller in the reach near Terre Haute than in the reach near Lafayette. The overall average of the absolute prediction error for all 10 equations was 22% for the reach near Terre Haute and 128% for the reach near Lafayette. Confidence limits of results obtained from the modified tracer technique were smaller than those obtained from the equations in the literature.

Indiana↗

USGS1983

Nonparametric tests for trends in water-quality data using the statistical analysis system

Two nonparametric procedures to test for trends in water-quality data (SEASKEN AND SEASRS) have been developed for the Statistical Analysis System* (SAS). The procedure SEASKEN tests for a monotonic trend in time by a modified form of Kendall's tau, the Seasonal Kendall test. The procedure SEASRS tests for a step trend between two different periods in a time series using a modified form of the Wilcoxon (Mann-Whitney) rank sum test, the Mann-WhitneyWilcoxon rank sum test for seasonal data. Examples are presented using the two procedures. The source code and user's guide for each of the two procedures are also presented. Procedures for flow adjusting water-quality data by the SAS procedures REG and SYSREG and techniques for plotting water-quality data as a time series by the SAS procedure PLOT are presented. Additionally, examples are presented to demonstrate the use of the U.S. Geological Survey procedures QWRETR, DVRETR, QWSAS, and DVINPUT to retrieve data from the Geological Survey WATSTORE system and make it available to SAS.

Open-File Report↗

USGS1981

Preliminary water-quality assessment of the upper White River near Indianapolis, Marion County, Indiana

The White River Park Commission is planning the development of park facilities along the White River through Indianapolis. A key element in the planning is the determination of whether water quality of the river is suitable for recreation. A preliminary water-quality assessment of the river in Indianapolis on August 4-5, 1980, indicates that, during low-flow steady-state conditions, water quality of the river is suitable for partial body contact recreation (any contact with water up to, but not including, complete submergence). Dissolved-oxygen concentrations varied but were higher than the Indiana water-quality standards established to ensure conditions for the maintenance of a well-balanced, warm-water fish community. High fecal-coliform densities that have been observed in the White River during high stream-flow are probably caused by stormwater runoff from combined sewers. However, during the low-flow steady-state conditions on August 4-5, 1980, fecal coliform densities were within the Indiana standards for partial body contact recreation. Concentrations of organic matter (based on biochemical-oxygen demand and dissolved- and suspended-organic carbon concentrations), nutrients, and heavy metals in the White River were generally within the limits recommended by the U.S. Environmental Protection Agency and were generally similar to values for other Indiana rivers. Chromium, copper, lead, zinc, and mercury are accumulating in bottom materials downstream from 30th Street (river mile 235.58). The source of these metals is probably stormwater runoff from combined sewer overflows. The phytoplankton densities of the White River were high (>500 cells per milliliter). The dominant phytoplankton species are indicative of rivers moderately affected by organic wastes. The highest cell concentrations, upstream from dams on the White River, significantly affected dissolved-oxygen concentration and pH.

Indiana↗

USGS1980

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for Little Lick and Big Lick Creeks, Blackford and Delaware counties, Indiana

The Indiana State Board of Health is developing a State water-quality management plan that includes establishing limits for liquid wastes discharged into Indiana streams. A digital computer model was used to predict alternatives for future waste loadings on Little Lick and Big Lick Creeks that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The model parameters included atmospheric reaeration, carbonaceous and nitrogenous biochemical-oxygen demand, and benthic-oxygen demand. The model was calibrated with data collected during three water-quality surveys at low flow. Verification of the model was not possible owing to varied effluent discharge during sampling. During these surveys, in-stream dissolved-oxygen concentration averaged less than 3 milligrams per liter, well below the State minimum requirement of 5.0 milligrams per liter. The model indicated that these low concentrations were caused by high waste loadings, lack of dilution, low reaeration, and benthic-oxygen demand. The hypothetical summer waste-assimilation study assumed that future reductions in discharge Loadings would decrease carbonaceous and benthic decay and increase nitrogenous decay. This hypothetical study indicated that projected effluent waste loads that would provide acceptable in-stream dis-solved-oxygen concentrations are highly dependent on rates of nitrification. Ammonia toxicity became the limiting water-quality criterion at low nitrification rates. The hypothetical winter waste-assimilation study indicated that projected dissolved-oxygen concentrations in Little Lick and Big Lick Creeks did not fall below the State standard. Owing to a lack of dilution, however, ammonia-nitrogen concentrations would violate in-stream toxicity standards in both Little Lick and Big Lick Creeks. In order to quantify the results of the waste-assimilation study, it would be necessary to collect additional stream data.

Indiana↗

USGS1980

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for Little Laughery Creek, Ripley and Franklin counties, Indiana

The Indiana State Board of Health is developing a State water-quality management plan that includes establishing Limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in Little Laughery Creek tributary and Little Laughery Creek was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. Natural streamflow during the summer and annual 7-day, 10-year low flow is zero. Headwater flow upstream from the wastewater-treatment facilities consists solely of process cooling water from an industrial discharger. This flow is usually Less than 0.5 cubic foot per second. Consequently, benefits from dilution are minimal. As a result, current and projected ammonia-nitrogen concentrations from the municipal discharges will result in in-stream ammonia-nitrogen concentrations that exceed the Indiana ammonia-nitrogen toxicity standards (maximum stream ammonia-nitrogen concentrations of 2.5 and 4.0 milligrams per liter during summer and winter low flows, respectively). This waste-Load assimilation study is not based on a verified model. The changes in stream water quality predicted by the model represent only possible stream responses to differing effluent conditions. Benthic-oxygen demand is probably the most significant factor affecting Little Laughery Creek and is probably responsible for the in-stream dis-solved-oxygen concentration being less than the Indiana stream dissolved-oxygen standard (5.0 milligrams per liter) during two water-quality surveys. After municipal dischargers complete advanced waste-treatment facilities, benthic-oxygen demand should be less significant in the stream dissolved-oxygen dynamics.

Indiana↗

USGS1980

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for Wabash River, Huntington County, Indiana

The Indiana State Board of Health is developing a State water-quality management plan that includes establishing limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in the Wabash River in Huntington County, Ind., was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The major point-source waste load affecting the Wabash River in Huntington County is the Huntington wastewater-treatment facility. The most significant factor potentially affecting the dissolved-oxygen concentration during summer low flows is nitrification. However, nitrification should not be a limiting factor on the allowable nitrogenous and carbonaceous waste loads for the Huntington wastewater-treatment facility during summer low flows if the ammonia-nitrogen toxicity standard for Indiana streams is met. This wasteload assimilation study is not based on a verified model. The changes in stream water quality predicted by the model represent only possible stream response to different effluent conditions. The dissolved-oxygen standard for Indiana streams, an average of 5.0 milligrams per liter, should be met during summer and winter Zow flows if the National Pollution Discharge Elimination System's 5-day, carbonaceous biochemical-oxygen demands of a monthly average concentration of 30 milligrams per liter and a maximum weekly average of 45 milligrams per liter are not exceeded.

Indiana↗

USGS1979

A one-dimensional, steady-state dissolved-oxygen model and waste-load assimilation study for Cedar Creek, Dekalb and Allen counties, Indiana

The Indiana State Board of Health is developing a State water-quality management plan that includes the establishing of limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in Cedar Creek was used to develop alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. All point-source waste loads affecting Cedar Creek are in the four incorporated municipalities of Auburn, Garrett, Huntertown, and Waterloo, in a primarily agricultural area. Avilla, because of its distance from Cedar Creek, does not significantly affect the water quality of the modeled segment. The model indicates that the dissolved-oxygen concentration of the Auburn wastewater effluent and nitrification are the most significant factors affecting the dissolved-oxygen concentration in Cedar Creek during summer low flows. The observed dissolved-oxygen concentration of the Auburn wastewater effluent was low, and averaged 30 percent of saturation. Whether the effluent is aerated before discharge will ultimately define the waste-load assimilative capacity of Cedar Creek. Projected nitrogenous biochemical-oxygen demand loads, from the Indiana State Board of Health, for the Auburn and Waterloo wastewater-treatment facilities will result in violations of the current instream dissolved-oxygen standard (5 milligrams per liter), even with an effluent dissolved-oxygen concentration of 80 percent saturation. Natural streamflow for Cedar Creek upstream from the confluence of Willow and Little Cedar Creeks is small compared with the waste discharge, so benefits of dilution for Waterloo and Auburn are minimal. Stream reaeration capacity is not sufficient to maintain an average dissolved-oxygen concentration of at least 5 milligrams per liter, the State's water-quality standard for streams. The model also indicates that, during winter low flows, ammonia toxicity, rather than dissolved oxygen, is the limiting water-quality criterion in the reach of Cedar Creek downstream from the wastewater-treatment facility at Auburn and the confluence of Garrett ditch. Ammonia-nitrogen concentrations predicted for 2978 through 2000 downstream from the Waterloo wastewater-treatment facility do not exceed Indiana water-quality standards for streams. Calculations of the stream's assimilative capacity indicate that future waste discharge in the Cedar Creek basin will be limited to the reaches between the Auburn wastewater-treatment facility and County Road 68.

Indiana↗

USGS1979

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for East Fork White River, Bartholomew County, Indiana

Indiana↗

USGS1979

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for South Fork Wildcat Creek, Clinton County, Indiana

The Indiana State Board of Health is developing a State water-quality management plan that includes establishing limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in South Fork Wildcat Creek was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. Natural streamflow during the 7-day, 10-year low flow is zero, so no benefit from dilution is provided. The Indiana State Board of Health's projected ammonia-nitrogen concentration for the Frankfort wastewater-treatment facility will violate the in-stream total ammonia-nitrogen standards of 2.5 milligrams per liter and 4.0 milligrams per liter during summer and winter low flows, respectively. The model indicates that nitrification and algal respiration were significant factors affecting the dissolved-oxygen dynamics of South Fork Wildcat Creek during two water-quality surveys. Stream water quality during the two water-quality surveys was degraded by the discharge of wastewater receiving only primary treatment. Benthic deposits resulting from this wastewater discharge seem to exert a considerable oxygen demand. The discharge of partially treated wastewater should be eliminated when a new wastewater-treatment facility becomes operational in mid-1979. Therefore, benthic-oxygen demand due to benthic deposits should become negligible at that time.

Indiana↗

USGS1979

A one-dimensional, steady-state, dissolved-oxygen model and waste-load assimilation study for Wildcat Creek, Howard County, Indiana

The Indiana State Board of Health is developing a water-quality management plan that includes establishing limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in Wildcat Creek was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The model indicates that benthic-oxygen demand is the most significant factor affecting the dissolved-oxygen concentrations in Wildcat Creek during summer low flows. The Indiana stream dissolved-oxygen standard should be met if the Kokomo wastewater-treatment facility meets its current National Pollution Discharge Elimination System permit restrictions (average monthly 5-day biochemical-oxygen demand of 5 milligrams per liter and maximum weekly 5-day biochemical-oxygen demand of 7.5 milligrams per liter) and benthic-oxygen demand becomes negligible. Ammonia-nitrogen toxicity may also be a water-quality limitation in Wildcat Creek. Ammonia-nitrogen waste loads for the Kokomo wastewater-treatment facility, projected by the Indiana State Board of Health, will result in stream ammonia-nitrogen concentrations that exceed the State standard (2.5 milligrams per liter during summer months and 4.0 milligrams per liter during winter months).

Indiana↗