|Hydrologic Unit Code (HUC):||05120201|
|Datum:||884.10 feet above NAVD88|
|Drainage Area:||4.6 square miles|
|County in which site is located:||Hendricks|
|Site managed by:||Indianapolis Office|
This station is operated and maintained in cooperation with the Indiana Department of Environmental Management.
Discrete suspended sediment and nutrient samples are collected routinely and intensively at this site. Discrete samples are collected manually by wading downstream of the CR 750N bridge at low flow or from the bridge during high water conditions. The sampling frequency is increased during the high flow season.
Concentrations from laboratory analysis of discrete samples and corresponding values from in-stream instruments are mathematically combined to develop a statistical surrogate model. Then, the model is used to compute real-time concentrations based on continuous in-stream sensor readings of another, more easily measured value. For example, turbidity is a typical in-stream measurement used as a surrogate for suspended-sediment concentration. Daily, monthly, and annual loads can be computed and compared to understand seasonal and annual variability.
The super gage at School Branch began operation in June of 2015. More than a year of data is needed to develop a surrogate model; however, potential models might predict suspended sediment, nitrate and phosphate concentrations in School Branch.
The objective of this six year study is to assess the impact of conservation cropping on water quantity and the physical, chemical, and biological indicators of stream water quality.
Conservation cropping systems are a combination of zero tillage, continuous cover crops, precision nutrient and pesticide application, and other techniques that improve soil health and promote agricultural production. A collaborative partnership of federal, state, and local agencies, a university research center, and agricultural producers has been formed to understand the effects on water quality and water quantity from 5 to 10 years of conservation cropping in the School Branch watershed near Indianapolis, Indiana.
Land use in the School Branch watershed upstream of the reservoir is 80 percent agricultural and 13 percent developed (residential and residential open space). Agricultural land classes include corn, soybeans, wheat, hay, and pasture. According to the NRCS, approximately 40 percent of the watershed area has conservation cropping systems that have been in place for 5-10 years. The percentages of agricultural land use and conservation cropping acreage change from north to south in the watershed. Land use north of Maloney Road is 89 percent agricultural and most of the land is not in conservation cropping. Farms with conservation cropping systems dominate the agricultural land use south of Maloney Road to CR 750N.
The study area for this project includes the School Branch watershed north of Noble Drive near CR 600N. The USGS and partners will investigate three reaches of School Branch, with the super gage featured here as the second of the three reaches. USGS streamgages are located at the most upstream and downstream reaches. At all three gages, representative water-quality samples will be collected routinely. Streamflow and water-quality data from the gages will enable comparisons of nitrogen, phosphorus, and suspended sediment in three reaches of School Branch. If the concentrations or loads (mass per unit time) of nitrogen, phosphorus, and suspended sediment show a spatial or temporal difference among these three stream reaches, one hypothesis will be that the difference is related to land use and conservation cropping.