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Research about Big Spring basin

Source-linked reports with geographic coverage including Big Spring basin.

3 recordsLinked to original sources

USGS1992

Hydrologic data for the Big Spring basin, Clayton County, Iowa, water year 1990

Hydrologic data were collected in the Big Spring basin located in Clayton County, Iowa, during the 1990 water year. The data were collected by the U.S. Geological Survey in cooperation with the Iowa Department of Natural Resources, Geological Survey Bureau, to provide information on variation and movement of agricultural chemicals in the hydrologic cycle in the basin. Precipitation, surface-water, and ground-water data were collected. Rainfall recorded during water year 1990 at a monitoring site on Roberts Creek totaled 43.67 inches. The greatest monthly rainfall (14.45 inches) occurred in August. Calcium and sulfate were the predominant ions in the rain, and the median concentrations of nitrate and ammonia as nitrogen were 0.35 and 0.48 milligrams per liter, respectively. Stream discharge, specific conductance, pH, and water temperature were monitored continuously, and monthly water-quality samples were collected at three sites in the basin. The predominant ions in samples from Roberts Creek at the point where it leaves the basin were calcium, magnesium, and bicarbonate. Nitrite plus nitrate as nitrogen concentrations in 42 samples ranged from less than 0.10 to 18 milligrams per liter. Pesticide concentrations in 34 samples ranged from less than 0.10 to 12 micrograms per liter. Alachlor was detected in 56 percent of the samples; atrazine in 100 percent; cyanazine in 68 percent; and metolachlor in 47 percent. At Big Spring, the ground-water discharge point, the daily mean specific conductance ranged from 378 to 796 microsiemens per centimeter at 25 degrees Celsius, the daily median pH ranged from 6.5 to 7.2, and the daily mean water temperature ranged from 5.5 to 11.5 degrees Celsius. Calcium, magnesium, and bicarbonate generally were the predominant ions in solution. Concentrations of nitrite plus nitrate as nitrogen in 32 samples ranged from 3.4 to 16 milligrams per liter. Alachlor was detected in 22 percent of the samples; atrazine in 100 percent; cyanazine in 44 percent, and metplachlor in 6 percent. The maximum atrazine concentration was 4.5 micrograms per liter. During a low-flow seepage study, May 29 and 30,1990, the measured discharge lost by streams in the basin was 8.56 cubic feet per second, the measured dissolved nitrogen load lost was 0.29 ton per day, and the measured atrazine load lost was 0.028 pound per day. The total measured discharge and total dissolved nitrogen load leaving the basin in streams were 3.63 cubic feet per second and about 0.04 ton per day, respectively.

Iowa↗

USGS1991

Hydrologic data for the Big Spring basin, Clayton County, Iowa; water year 1989

Hydrologic data were collected in the Big Spring Basin located in Clayton County, Iowa, during the 1989 water year. The data were collected in cooperation with the Iowa Department of Natural Resources, Geological Survey Bureau, to provide information on variation and movement of agricultural chemicals in the hydrologic cycle in the Big Spring Basin. Precipitation, stream, and ground-water data were collected. Total rainfall in the basin ranged from 20.0 to 24.4 inches. The greatest monthly rainfall was in August. Calcium and sulfate were the predominant ions in the rain and the median nitrate and ammonia concentrations as nitrogen were 0.40 and 0.63 mg/L (milligrams per liter), respectively. Stream discharge, water temperature, specific conductance, and pH were monitored continuously, and monthly water-quality samples were collected at three sites in the basin. The predominant ions in Roberts Creek, at the site where it leaves the basin, were calcium, magnesium, and bicarbonate. Nitrate plus nitrite as nitrogen concentrations ranged from 0.2 to 6.2 mg/L. Pesticide concentrations in 23 samples ranged from less than 0.10 μ /L (micrograms per liter) to 4.4 μ /L. Atrazine was detected in 100 percent of the samples, cyanazine and metolachlor in 43 percent of the samples and alachlor in 35 percent of the samples. At Big Spring, the ground-water discharge point, the daily mean water temperature ranged from 5.1 to 10.6 degrees Celsius, the daily mean specific conductance ranged from 271 to 793 micro Siemens per centimeter at 25 degrees Celsius, and the daily median pH ranged from 63 to 7.1. Calcium, magnesium, and bicarbonate were the predominant ions in solution. Nitrate plus nitrite as nitrogen concentrations ranged from 2.0 to 7.4 mg/L. Atrazine was detected in 95 percent of the samples, cyanazine was detected in 26 percent of the samples, and metolachlor and alachlor were detected in 16 percent of the samples. The maximum atrazine concentration was 3.3 μ /L. Water levels in the unconsolidated aquifers and the Galena aquifer were highest in the spring after snowmelt and in September after the greatest monthly rainfall. Water levels in the Saint Peter aquifer declined by approximately 0 J to 3.0 feet. During a baseflow seepage study, August 16 and 17, the measured discharge lost by streams in the basin was 2.82 cubic feet per second, the measured dissolved nitrogen load lost was 80 pounds per day, and the measured atrazine load lost was 0.002 pound per day. The total measured discharge and total dissolved nitrogen load leaving the basin in streams was 0.07 cubic feet per second and less than 20 pounds per day, respectively.

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USGS1989

Hydrologic data for the Big Spring basin, Clayton County, Iowa, water year 1988

Hydrologic data was collected during the 1988 water year in cooperation with the Iowa Department of Natural Resources Geological Survey Bureau in the Big Spring ground-water basin located in Clayton County, Iowa. Information on precipitation, streams, and ground water was collected in the basin. Total rainfall at Big Spring was 24.08 inches. The greatest monthly rainfall was in September. Calcium and sulfate were the predominant ions in the rain and the median ammonia and nitrate concentrations as nitrogen were 0.40 and 0.37 mg/L (milligrams per liter), respectively. Stream discharge, water temperature, specific conductance, and pH were monitored continuously and monthly water-quality samples were collected at three sites in the basin. In the streams, water temperature and pH vary diurnally and are greatest during the day. Specific conductance varies inversely with water temperature and pH. The predominant ions in the streams were calcium, magnesium, and bicarbonate. Nitrate plus nitrite as nitrogen concentrations ranged from 0.5 to 15 mg/L. Pesticide concentrations ranged from less than 0.10 µ g/L (micrograms per liter) to 0.72 µ g/L. Atrazine was detected in 12 of 13 stream samples and cyanazine was detected in 4 of 13 samples. The daily mean temperature of the water in Big Spring ranged from 9.7 to 10.6 degrees Celsius, the daily mean specific conductance ranged from 698 to 735 microsiemens per centimeter at 25 degrees Celsius, and the daily median pH ranged from 6.7 to 7.1. Calcium, magnesium, and bicarbonate were the predominant ions in solution. Nitrate plus nitrite as nitrogen concentrations ranged from 7.5 to 11 mg/L. Atrazine was the only pesticide detected in the monthly samples from Big Spring. Atrazine concentrations were greater than the detection limit in six of seven samples and ranged from less than 0.10 to 0.26 µ g/L. During a baseflow seepage study, June 28 and 29, the discharge lost by streams in the basin was 5.57 cubic feet per second and the dissolved nitrogen load lost was 0.19 tons per day. The discharge and total dissolved nitrogen leaving the basin in streams was 2.93 cubic feet per second and 0.02 tons per day, respectively.

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