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Site content related to keyword: "environmental sensors"

RI79 Simulation of Groundwater Flow and Contaminant Transport in Eastern Sussex County, Delaware With Emphasis on Impacts of Spray Irrigation of Treated Wastewater

Simulation of Groundwater Flow and Contaminant Transport in Eastern Sussex County, Delaware With Emphasis on Impacts of Spray Irrigation of Treated Wastewater

This report presents a conceptual model of groundwater flow and the effects of nitrate (NO3-) loading and transport on shallow groundwater quality in a portion of the Indian River watershed, eastern Sussex County, Delaware. Three-dimensional, numerical simulations of groundwater flow, particle tracking, and contaminant transport were constructed and tested against data collected in previous hydrogeological and water-quality studies.

The simulations show a bimodal distribution of groundwater residence time in the study area, with the largest grouping at less than 10 years, the second largest grouping at more than 100 years, and a median of approximately 29 years.

Historically, the principal source of nitrate to the shallow groundwater in the study area has been from the chemical- and manure-based fertilizers used in agriculture. A total mass of NO3- -nitrogen (N) of about 169 kg/day is currently simulated to discharge to surface water. As the result of improved N-management practices, after 45 years a 20 percent decrease in the mass of NO3- -N reaching the water table would result in an approximately 4 percent decrease in the mass of simulated N discharge to streams. The disproportionally smaller decrease in N discharge reflects the large mass of N in the aquifer coupled with long groundwater residence times.

Currently, there are two large wastewater spray irrigation facilities located in the study domain: the Mountaire Wastewater Treatment Facility and Inland Bays Wastewater Facility. The effects of wastewater application through spray irrigation were simulated with a two-step process. First, under different operations and soil conditions, evaporation and water flux, NO3- -N uptake by plants, and NO3- -N leaching were simulated using an unsaturated flow model, Hydrus-1D. Next, the range of simulated NO3- -N loads were input into the flow and transport model to study the impacts on groundwater elevation and NO3- -N conditions.

Over the long term, the spray irrigation of wastewater may increase water-table elevations up to 2.5m and impact large volumes of groundwater with NO3-. Reducing the concentration of NO3- in effluent and increasing the irrigation rate may reduce the volumes of water impacted by high concentrations of NO3-, but may facilitate the lateral and vertical migration of NO3-. Simulations indicate that NO3- will eventually impact deeper aquifers. An optimal practice of wastewater irrigation can be achieved by adjusting irrigation rate and effluent concentration. Further work is needed to determine these optimum application rates and concentrations.

New Instrumentation for Water Budget Evaluation

New eddy covariance instrument for measuring evapotranspiration

The Delaware Environmental Observation System (DEOS) and the Delaware Geological Survey have recently acquired new instrumentation to measure evapotranspiration (ET). The purchase of an eddy covariance instrument, partially supported by the Department of Natural Resources and Environmental Control, will improve the ability to quantify ET during agricultural and water supply drought periods and improve water availability estimates for resource managers.

Project Update: NEWRnet - North East Water Resources Network

Monitoring station at Coursey Pond outlet

Infrastructure that will support the NEWRNet water quality monitoring station was installed at the main outflow of Coursey Pond on the fish ladder on April 23, 2014.

NEWRnet - North East Water Resources Network

NEWRnet study sites
Project Contact(s):

The North East Water Resources (NEWRnet) consortium of EPSCoR jurisdictions of Delaware (DE), Rhode Island (RI), and Vermont (VT) will create an advanced sensor network in watersheds for gathering high-frequency, spatially-extensive water quality and quantity data and a network of lab and field-based experiments and agent-based models to investigate how to align sensor data and their visualization with utilization by stakeholders. DGS is participating in the watershed sensing network by installing and operating a nitrogen and organic carbon sensor and stream discharge monitoring station in the Murderkill River watershed, and collaborating with the project team to interpret results.

EPSCoR Track 2 - New grant from NSF EPSCoR will establish water resources network

Geographer Dan Leathers (standing), a lead principal investigator on the Delaware-Rhode Island-Vermont EPSCoR RII Track-2 grant, works with colleagues John Callahan of the Delaware Geological Survey and Kevin Brinson of the Delaware Environmental Observing System to download data from an environmental sensor to a laptop computer for analysis.

The Delaware Experimental Program to Stimulate Competitive Research (EPSCoR) is a partner in a three-year, $6-million grant from the National Science Foundation through its EPSCoR Research Infrastructure Improvement Track-2 program.

The grant program supports research by consortia of EPSCoR jurisdictions. Through this award, Delaware will join with the EPSCoR programs in Rhode Island and Vermont to form the North East Water Resources Network (NEWRnet). Two million dollars of the grant will go to each of the three states involved.